This communication presents a new method of detecting the behaviour pattern in Sprague-Dawley (SD) rats based on the measurement of the dielectric properties of blood plasma at microwave frequencies at different perio...This communication presents a new method of detecting the behaviour pattern in Sprague-Dawley (SD) rats based on the measurement of the dielectric properties of blood plasma at microwave frequencies at different periods of time. The microwave measurements were performed by rectangular cavity perturbation method in the S-band of microwave frequency with the blood plasma collected from normal rats (Controls) as well as chemically induced rats (Aβ). A change is observed in the dielectric properties of the Aβsamples but not the controls samples at the extended period of time. This measurement technique is simple and the collection of blood from the rats is nonsurgical in nature. These results prove a new method of diagnosing Alzheimer’s Disease (AD) using microwave techniques.展开更多
Diethylnitrosamine (DENA) is able to induce various benign and malignant liver lesions in rats with a high success rate and a low mortality rate. It provides a more appropriate model that better simulates the various ...Diethylnitrosamine (DENA) is able to induce various benign and malignant liver lesions in rats with a high success rate and a low mortality rate. It provides a more appropriate model that better simulates the various lesions occurring in humans than the usual model of tumor implantations. The aim of the present study was to evaluate MRI liver examination in Sprague-Dawley(SD) rats as a routine method to detect hepatocellular carcinoma (HCC) nodules induced by DENA and to follow up their growth. METHODS:Hepatic carcinogenesis was induced in 80 male SD rats using oral DENA solution. All animals were imaged for liver tumor detection with a 1.5 Tesla magnet (Siemens Sonata,Erlangen, Germany) using correspondence scan parameters and a radio-frequency knee coil. Macroscopic examinations were performed along the axial MRI sections to evaluate magnetic resonance imaging (MRI) findings, and histopathological assessment was also performed. RESULTS:No false negative results were obtained on MR images. Hepatic tumors in 72 rats were confirmed macro-scopically and 68 rats were detected by MRI till the 20th week. The smallest and the largest nodules detected by MRI were 2 mm and 37 mm in diameter respectively. The agreement rate of MRI with macroscopic observation was 39. 1% and 97. 4% respectively for 2 mm to 5 mm and more than 5 mm nodules. CONCLUSIONS:The hepatic tumor induced by DENA provides a more representative range of tumors for imaging diagnosis and interventional treatment. MRI is the best approach for scrutinizing pathological changes of rat livers in the period of observation.展开更多
An aging-induced decrease in Schwann cell viability can affect regeneration following peripheral nerve injury in mammals. It is therefore necessary to investigate possible age-related changes in gene expression that m...An aging-induced decrease in Schwann cell viability can affect regeneration following peripheral nerve injury in mammals. It is therefore necessary to investigate possible age-related changes in gene expression that may affect the biological function of peripheral nerves. Ten 1-week-old and ten 12-month-old healthy male Sprague-Dawley rats were divided into young(1 week old) and adult(12 months old) groups according to their ages. mRNA expression in the sciatic nerve was compared between young and adult rats using next-generation sequencing(NGS) and bioinformatics(n = 4/group). The 18 groups of differentially expressed mRNA(DEmRNAs) were also tested by quantitative reverse transcription polymerase chain reaction(n = 6/group). Results revealed that(1) compared with young rats, adult rats had 3608 groups of DEmRNAs. Of these, 2684 were groups of upregulated genes, and 924 were groups of downregulated genes. Their functions mainly involved cell viability, proliferation, differentiation, regeneration, and myelination.(2) The gene with the most obvious increase of all DEmRNAs in adult rats was Thrsp(log2 FC = 9.01, P 〈 0.05), and the gene with the most obvious reduction was Col2 a1(log2 FC = -8.89, P 〈 0.05).(3) Gene Ontology analysis showed that DEmRNAs were mainly concentrated in oligosaccharide binding, nucleotide-binding oligomerization domain containing one signaling pathway, and peptide-transporting ATPase activity.(4) Analysis using the Kyoto Encyclopedia of Genes and Genomes showed that, with increased age, DEmRNAs were mainly enriched in steroid biosynthesis, Staphylococcus aureus infection, and graft-versus-host disease.(5) Spearman's correlation coefficient method for evaluating NGS accuracy showed that the NGS results and quantitative reverse transcription polymerase chain reaction results were positively correlated(rs = 0.74, P 〈 0.05). These findings confirm a difference in sciatic nerve gene expression between adult and young rats, suggesting that, in peripheral nerves, cells and the microenvironment change with age, thus influencing the function and repair of peripheral nerves.展开更多
BACKGROUND: Studies have demonstrated that selective innervation of the sacral nerve tract to the bladder plays an important role in bladder functional reconstruction following spinal cord injury. However, there are ...BACKGROUND: Studies have demonstrated that selective innervation of the sacral nerve tract to the bladder plays an important role in bladder functional reconstruction following spinal cord injury. However, there are very few studies reporting detailed morphological characteristics of urogenital center and lumbosacral nerve roots. OBJECTIVE: To analyze the spinal cord segment of the lumbosacral spinal cord urogenital center, and to observe morphological characteristics. DESIGN, TIME AND SETTING: A neuroanatomical study was performed at the Laboratory of Neuroanatomy, Peking University Health Science Center between September 2007 and March 2008. MATERIALS: Horseradish peroxidase-conjugated cholera toxin B subunit (CB-HRP) was purchased from Sigma, USA; surgical microscope was purchased from Zhenjian Zhongtian Optical Instrument, Jiangsu Province, China; BCL-420 biological and functional experimental system was purchased from Taimeng Science and Technology, Sichuan Province, China. METHODS: A total of 36 adult, Sprague Dawley rats were randomly assigned to groups A (n = 10), B (n = 10), C (n = 10), and D (n = 6). CB-HRP (3%, 10-15 μL) was injected into the bladder detrusor muscle (group A), external urethral sphincter (group B), and perineal muscles (group C), respectively. Rats in group D were not given any treatments. MAIN OUTCOME MEASURES: At 72 hours after CB-HRP injection, CB-HRP-positive neurons were analyzed in lumbosacral segments using 3, 3', 5, 5'-tetramethylbenzidine staining and an Olympus optic microscope, while anatomical structures in the respective spinal nerve tract were observed using a surgical microscope. RESULTS: CB-HRP-positive neurons were distributed in the L6-S1 segments of the spinal cord, and neurons primarily innervating the bladder detrusor muscle were located at the sacral parasympathetic nucleus and the intermediolateral nucleus. In addition, neurons that primarily innervate the external urethral sphincter and perineal muscles were observed in the ventrolateral portion (Onuf's nucleus). The lumbar-sacral nerve roots were composed of varying nerve tracts, Le., they were typically divided into 1-2 sub-bundles, and the sub-bundles were then divided into 2-3 tiny bundles. There were extensive fibro-connections between the rootlets. CONCLUSION: The urogenital center in Sprague Dawley rats was located in the L6 -S1 segments of the spinal cord, and the rootlets were clearly observed. Therefore, this rat experimental model could be utilized for highly selective anterior/posterior rhizotomy.展开更多
Background: Lack of available reference values in a research setting under local conditions can be a drawback for beginners, as the accuracy of data from control samples cannot be checked at the beginning of a researc...Background: Lack of available reference values in a research setting under local conditions can be a drawback for beginners, as the accuracy of data from control samples cannot be checked at the beginning of a research project. This affects comparisons with data from test samples. To avoid these complications in their research projects,beginners tend to have a greater number of animals in the control group compared to test groups in order to have control group measurements within 2 SDs of the mean.Methods: As non-availability of reference values was a long-felt need, the described project was conducted in order to establish a reference database for selected haematological, biochemical and physiological parameters using apparently healthy Sprague-Dawley rats bred in the Animal House of Faculty of Medicine, University of Colombo(UCFM).Results: Differences in mean values of packed cell volume(PCV), mean corpuscular volume(MCV) and mean corpuscular hemoglobin concentration(MCHC), serum creatinine and blood glucose levels between the two genders were statistically significant. Lipid profile measurements did not differ significantly between genders, but mean and median values of triglycerides(TG) between male and female rats showed a difference of more than 10 mg/dL. The liver enzymes alkaline phosphatase(AP)and aspartate aminotransferase(AST) were also statistically significantly different between sexes. Despite wide variation in mean alanine aminotransferase(ALT)between sexes, the difference was not statistically significant.Conclusion: The findings of this project should support to a certain extent the"Reduction" aspect of the 3 Rs concept of Russell and Burch by reducing the number of Sprague-Dawley rats used in future research projects at UCFM.展开更多
AIM: To further clarify the changes occurred in the testicular capsulotomized rats. METHODS: In testicular capsulotomized and sham-operated rats, the cross sectional area, the nucleus diameter and the number of Leydig...AIM: To further clarify the changes occurred in the testicular capsulotomized rats. METHODS: In testicular capsulotomized and sham-operated rats, the cross sectional area, the nucleus diameter and the number of Leydig cells were morphologically analyzed by the Vidas Image Processing System connected to a microscope. RESULTS: In the capsulotomized animals, the cross sectional area of Leydig cells was gradually increased from 30 days onwards. There was no obvious change in the nucleus diameter of Leydig cells. However, The Leydig cell number was significantly increased from day 30 onwards. CONCLUSION: In rats, testicular capsulotomy may induce hyperplasia/hypertrophy of Leydig cells in the testis.展开更多
The use of plant parts (leaves, flowers, stems, barks, roots etc.) in traditional medicine is increasingly gaining ground in modern medicine, as plant sources have long been recognized as sources of secondary metaboli...The use of plant parts (leaves, flowers, stems, barks, roots etc.) in traditional medicine is increasingly gaining ground in modern medicine, as plant sources have long been recognized as sources of secondary metabolites which can be used to treat a wide range of diseases. The effect of extracts of Justicia secunda leaves on red blood cells (RBC) count and haemoglobin (Hb) concentration was investigated in adult Sprague-Dawley rats to establish haematinic activity. Phenylhydrazine (PHZ)-induced anaemic rats were treated with water, methanol or ethyl acetate extracts at 200 mg/kg body weight. RBC counts and Hb concentration were analysed using a haematology analyser at 3-day intervals for 21 days. The extracts were compared with rats administered the haematinic tonic Feroglobin®?and vehicle-treated (normal saline). Rats administered the water extract exhibited the most significant increase (P ) in the number of RBCs and Hb concentration compared with the vehicle-treated PHZ-induced anaemic rats. Rats administered the methanol extract followed with significant increase (P ) in RBC counts and Hb concentration (J. secunda leaves has excellent haematinic properties and this provides the pharmacological basis of its use in Ghanaian traditional medicine for the treatment of anaemia.展开更多
ATP was added to the cultured sensory neurons obtained from the dorsal root ganglia of the neonatal rats and PBS was added to serve as control. MTT assays were conducted to evaluate the survival and activity of the cu...ATP was added to the cultured sensory neurons obtained from the dorsal root ganglia of the neonatal rats and PBS was added to serve as control. MTT assays were conducted to evaluate the survival and activity of the cultured neurons. And the silicone regenerative chamber was used after the sciatic nerve incision of the mature SD rat. 1 mmol/L ATP was injected into the left chamber and 0.09 % natrium chloride was injected into the right chamber as controls. The changes of nitric oxide synthase (NOS) activity in the corresponding dorsal root ganglia were measured histochemically and image analysis was also performed 4 days after the sciatic nerve injury. The results showed that extracellular ATP could enhance the survival of the neurons and the number of NOS positive neurons were significantly different between the ATP and control groups ( P <0.05). It was suggested that extracellular ATP had neurotrophic effect on neurons survival and could inhibit the NOS activity of the sensory neurons after the peripheral nerve incision, hence exerting the protective effect on the neurons, which was valuable for nerve regeneration after nerve injury.展开更多
The posterior rootlets in L6 and S1 spinal cord of adult male Sprague-Dawley rats underwent electrostimulation. The bladder pressure, urethral perfusion pressure and intracavernous pressure were recorded. When some po...The posterior rootlets in L6 and S1 spinal cord of adult male Sprague-Dawley rats underwent electrostimulation. The bladder pressure, urethral perfusion pressure and intracavernous pressure were recorded. When some posterior rootlets of L6 and Sl were electrostimulated, the intracavernous pressure peaked rapidly, but the bladder pressure and the urethral perfusion pressure curve did not show great change. When other rootlets were stimulated, the bladder pressure changed greatly, but the urethral perfusion pressure and the intracavernous pressure did not show great change. When different rootlets were stimulated, the urethral perfusion pressure changed maximally, but there were no great changes in bladder pressure or intracavernous pressure. Furthermore, stimulation of some rootlets produced simultaneous changes in two or three different pressure measures mentioned above. The results demonstrate that regulation by L6 and S1 posterior rootlets of the rat bladder detrusor, external urethral sphincter and penis cavernous body are significantly distinct. Different rootlets can be distinguished by electrostimulation.展开更多
Objective To evaluate the combined subchronic toxicity of bisphenol A(BPA) and dibutyl phthalate(DBP) in male Sprague Dawley(SD) rats.Methods Forty 4‐week‐old male rats weighing 115‐125 g were randomly divide...Objective To evaluate the combined subchronic toxicity of bisphenol A(BPA) and dibutyl phthalate(DBP) in male Sprague Dawley(SD) rats.Methods Forty 4‐week‐old male rats weighing 115‐125 g were randomly divided into BPA‐treated,DBP‐treated group,BPA+DBP‐treated and control groups and fed with a soy‐ and alfalfa‐free diet containing 285.4 ppm BPA,285.4 ppm DBP,285.4 ppm BPA plus 285.4 ppm DBP,and a control diet,respectively,for 90 consecutive days.At the end of the study,the animals were sacrificed by exsanguination via the carotid artery under diethyl etherane aesthesia and weighed.Organs,including liver,kidneys,spleen,thymus,heart,brain,and testis underwent pathological examination.The androgen receptor(AR),gonadotropin‐releasing hormone receptor(GNRHR),and progesterone hormone receptor(PR) genes from the hypothalamus were detected by real‐time PCR.The biomedical parameters were analyzed.Results No significant difference was found in food intake,body weight,tissue weight,organ/brain weight ratio,and biomedical parameters among the four groups(P〉0.05).However,BPA and DBP up‐regulated AR,PR and GNRHR expression levels in rats and showed a synergistic or an additive effect in the BPA+DBP group.Conclusion The combined subchronic toxicity of BPA and DBP is synergistic or additive in male SD rats.展开更多
Experimental models have allowed inquiry into the pathophysiology of varicocele (VC) beyond that possible with human patients. A randomized controlled study in rats was designed to clarify the influence of the degre...Experimental models have allowed inquiry into the pathophysiology of varicocele (VC) beyond that possible with human patients. A randomized controlled study in rats was designed to clarify the influence of the degree of left renal vein constriction on the development of adolescent VC. Fifty adolescent male Sprague-Dawley rats (Rattus norvegicus) were randomly assigned to five groups of 10: the experimental groups (I-IV) underwent partial ligation of left renal veins with 0.5-, 0.6-, 0.7-, and 0.8-mm diameter needles, respectively. The control group (V) underwent a sham operation. The diameter of the left spermatic vein (LSV) was measured at baseline and 30 days postoperatively. In addition, the lesion of the left kidney was examined with the naked eye and assessed by Masson's trichrome staining. VC was successfully induced in 2 (20%), 4 (40%), 7 (70%), and 10 (100%) rats in groups I-IV, respectively. The other rats failed to develop VCs primarily due to left renal atrophy. No VC was observed in group V. The postsurgical LSV diameters in VC rats in groups III and IV were 1.54 ± 0. 16 and 1.49 ± 0.13 mm, respectively (P〉 0.05), and their increments were 1.36±0. 10 and 1.31±0. 10 ram, respectively (P 〉 0.05). These results suggest that suitable constriction of the left renal vein is critical for adolescent VC development. In addition, the 0.8-mm diameter needle may be more suitable for inducing left renal vein constriction in adolescent rat models.展开更多
Objective: To investigate the wound-healing effect of Alocasia longiloba(A. longiloba) petiole extract on wounds in rats.Methods: Twenty-two male Sprague-dawley rats were randomly assigned to receive 10% solcoseryl ge...Objective: To investigate the wound-healing effect of Alocasia longiloba(A. longiloba) petiole extract on wounds in rats.Methods: Twenty-two male Sprague-dawley rats were randomly assigned to receive 10% solcoseryl gel, phosphate buffer saline, 50% ethanol, 95% ethanol and hexane extracts of A. longiloba at 1.5%, 3% and 6% doses, respectively. A full thicknesses wound(6 mm) was created on the dorsal of the rat; and all rats were applied with the extract solutions, 10% solcoseryl gel and phosphate buffer saline once a day topically until day 12. The wound was photographed on day 1, 6 and 12, and the percentage of wound contraction was calculated. On day 12, rats were sacrificed and histological examination of granulation tissue was carried out using haematoxylin & eosin and Masson's Trichrome stain to determine the wound healing effect.Results: In this study, 6% of 50% and 95% ethanol extracts of A. longiloba showed 82.50% and 82.32% wound contraction, respectively, and were comparable with 10% solcoseryl gel(82.30%). Meanwhile, phosphate buffer saline treated group showed the lowest wound contraction(69.86%). Histological assessment of wound treated with 6% of 95% ethanol extract of A. longiloba showed distinct epidermal and dermal layer, higher proliferation of fibroblast and more angiogenesis with collagen compared to other wound treated groups.Conclusions: A. longiloba petiole extracts have a wound healing potential and 6% of 95% ethanol extract of A. longiloba is more effective. Further studies are required to understand the wound healing mechanism of action of the extract.展开更多
This study was carried out to find out if alligator pepper can prevent the development of fetal macrosomia in Sprague-Dawley rats fed with high glycemic index diet. Fifteen adult female Sprague-Dawley rats of proven f...This study was carried out to find out if alligator pepper can prevent the development of fetal macrosomia in Sprague-Dawley rats fed with high glycemic index diet. Fifteen adult female Sprague-Dawley rats of proven fertility were acclimatized for a period of two weeks in a well-ventilated laboratory and fed with grower’s mash and water ad libitum. Thereafter, they were randomly placed in separate cages after which a male Sprague-Dawley rat of proven fertility was introduced into each of the cages containing the female rats. They were left in the cages for three days during, which mating was confirmed to have occurred. The male rats were then withdrawn from the female rats, which were placed in separate maternity cages. The female rats were randomly allocated to three groups A, B and C so there were 5 pregnant rats in each group. The rats in group A were fed with 50 g of grower’s mash daily while the rats in groups B and C were fed with 50 g of cooked fermented cassava respectively. All rats were given water ad libitum throughout the duration of the experiment. The rats in groups A and B were intraperitoneally injected with 13.3 ml per Kg body weight of distilled water while the rats in group C were intraperitoneally injected with 13.3 mg/Kg body weight of aqueous extract of alligator pepper respectively. They were observed for 18 - 25 days. The litters of the rats in group B had a significantly higher mean weight than the rats in group A while the litters of the rats in group C had a significantly lower mean weight than the rats in groups B. It was concluded that intraperitoneally injected aqueous extract of alligator pepper, in the first trimester of pregnancy, can prevent the development of fetal macrosomia in Sprague-Dawley rats.展开更多
Objective To investigate the effects of different electromagnetic fields on some haematochemical parameters of circadian rhythms in Sprague-Dawley rats. Methods The study was carried out in 18 male and 18 female rats ...Objective To investigate the effects of different electromagnetic fields on some haematochemical parameters of circadian rhythms in Sprague-Dawley rats. Methods The study was carried out in 18 male and 18 female rats in good health conditions exposed to 50 Hz magnetic sinusoid fields at the intensity of 1000 μT, 100 μT, and 0 μT (control group) respectively, and in 18 male and 18 female rats in good health conditions exposed to 1.8 GHz electromagnetic fields at the intensity of 50 V/m, 25 V/m and 0 V/m (control group), respectively. Following haematochemical parameters for glucose, triglycerides, and total cholesterol were measured. Results Different effects of electromagnetic fields on circadian rhythms of both male and female rats were observed. Different changes occurred in some haematochemical parameters for glucose, triglycerides, and total cholesterol (P〈0.05). Conclusion Exposure to different electromagnetic fields is responsible for the variations of some haematochemical parameters in rats.展开更多
文摘This communication presents a new method of detecting the behaviour pattern in Sprague-Dawley (SD) rats based on the measurement of the dielectric properties of blood plasma at microwave frequencies at different periods of time. The microwave measurements were performed by rectangular cavity perturbation method in the S-band of microwave frequency with the blood plasma collected from normal rats (Controls) as well as chemically induced rats (Aβ). A change is observed in the dielectric properties of the Aβsamples but not the controls samples at the extended period of time. This measurement technique is simple and the collection of blood from the rats is nonsurgical in nature. These results prove a new method of diagnosing Alzheimer’s Disease (AD) using microwave techniques.
基金This study was supported by grants from specialized Research Fund for the Doctoral Program of Higher Education (SRFDP) (20030b10090)China Medical Board of New York (CMB 82-412) the TCM Administration Bureau of Sichuan Province (TCM 2004 B03).
文摘Diethylnitrosamine (DENA) is able to induce various benign and malignant liver lesions in rats with a high success rate and a low mortality rate. It provides a more appropriate model that better simulates the various lesions occurring in humans than the usual model of tumor implantations. The aim of the present study was to evaluate MRI liver examination in Sprague-Dawley(SD) rats as a routine method to detect hepatocellular carcinoma (HCC) nodules induced by DENA and to follow up their growth. METHODS:Hepatic carcinogenesis was induced in 80 male SD rats using oral DENA solution. All animals were imaged for liver tumor detection with a 1.5 Tesla magnet (Siemens Sonata,Erlangen, Germany) using correspondence scan parameters and a radio-frequency knee coil. Macroscopic examinations were performed along the axial MRI sections to evaluate magnetic resonance imaging (MRI) findings, and histopathological assessment was also performed. RESULTS:No false negative results were obtained on MR images. Hepatic tumors in 72 rats were confirmed macro-scopically and 68 rats were detected by MRI till the 20th week. The smallest and the largest nodules detected by MRI were 2 mm and 37 mm in diameter respectively. The agreement rate of MRI with macroscopic observation was 39. 1% and 97. 4% respectively for 2 mm to 5 mm and more than 5 mm nodules. CONCLUSIONS:The hepatic tumor induced by DENA provides a more representative range of tumors for imaging diagnosis and interventional treatment. MRI is the best approach for scrutinizing pathological changes of rat livers in the period of observation.
基金supported by the National Natural Science Foundation of China,No.81201546(to YXL)the Doctoral Start-up Program of Natural Science Foundation of Guangdong Province of China,No.2017A030310302(to ZWZ)+1 种基金the Medical Scientific Research Foundation of Guangdong Province of China,No.A2016018(to BH)the Science and Technology Project of Guangdong Province of China,No.2016A010103012(to JHL)
文摘An aging-induced decrease in Schwann cell viability can affect regeneration following peripheral nerve injury in mammals. It is therefore necessary to investigate possible age-related changes in gene expression that may affect the biological function of peripheral nerves. Ten 1-week-old and ten 12-month-old healthy male Sprague-Dawley rats were divided into young(1 week old) and adult(12 months old) groups according to their ages. mRNA expression in the sciatic nerve was compared between young and adult rats using next-generation sequencing(NGS) and bioinformatics(n = 4/group). The 18 groups of differentially expressed mRNA(DEmRNAs) were also tested by quantitative reverse transcription polymerase chain reaction(n = 6/group). Results revealed that(1) compared with young rats, adult rats had 3608 groups of DEmRNAs. Of these, 2684 were groups of upregulated genes, and 924 were groups of downregulated genes. Their functions mainly involved cell viability, proliferation, differentiation, regeneration, and myelination.(2) The gene with the most obvious increase of all DEmRNAs in adult rats was Thrsp(log2 FC = 9.01, P 〈 0.05), and the gene with the most obvious reduction was Col2 a1(log2 FC = -8.89, P 〈 0.05).(3) Gene Ontology analysis showed that DEmRNAs were mainly concentrated in oligosaccharide binding, nucleotide-binding oligomerization domain containing one signaling pathway, and peptide-transporting ATPase activity.(4) Analysis using the Kyoto Encyclopedia of Genes and Genomes showed that, with increased age, DEmRNAs were mainly enriched in steroid biosynthesis, Staphylococcus aureus infection, and graft-versus-host disease.(5) Spearman's correlation coefficient method for evaluating NGS accuracy showed that the NGS results and quantitative reverse transcription polymerase chain reaction results were positively correlated(rs = 0.74, P 〈 0.05). These findings confirm a difference in sciatic nerve gene expression between adult and young rats, suggesting that, in peripheral nerves, cells and the microenvironment change with age, thus influencing the function and repair of peripheral nerves.
基金Supported by: the National Natural Science Foundation of China, No. 30672096
文摘BACKGROUND: Studies have demonstrated that selective innervation of the sacral nerve tract to the bladder plays an important role in bladder functional reconstruction following spinal cord injury. However, there are very few studies reporting detailed morphological characteristics of urogenital center and lumbosacral nerve roots. OBJECTIVE: To analyze the spinal cord segment of the lumbosacral spinal cord urogenital center, and to observe morphological characteristics. DESIGN, TIME AND SETTING: A neuroanatomical study was performed at the Laboratory of Neuroanatomy, Peking University Health Science Center between September 2007 and March 2008. MATERIALS: Horseradish peroxidase-conjugated cholera toxin B subunit (CB-HRP) was purchased from Sigma, USA; surgical microscope was purchased from Zhenjian Zhongtian Optical Instrument, Jiangsu Province, China; BCL-420 biological and functional experimental system was purchased from Taimeng Science and Technology, Sichuan Province, China. METHODS: A total of 36 adult, Sprague Dawley rats were randomly assigned to groups A (n = 10), B (n = 10), C (n = 10), and D (n = 6). CB-HRP (3%, 10-15 μL) was injected into the bladder detrusor muscle (group A), external urethral sphincter (group B), and perineal muscles (group C), respectively. Rats in group D were not given any treatments. MAIN OUTCOME MEASURES: At 72 hours after CB-HRP injection, CB-HRP-positive neurons were analyzed in lumbosacral segments using 3, 3', 5, 5'-tetramethylbenzidine staining and an Olympus optic microscope, while anatomical structures in the respective spinal nerve tract were observed using a surgical microscope. RESULTS: CB-HRP-positive neurons were distributed in the L6-S1 segments of the spinal cord, and neurons primarily innervating the bladder detrusor muscle were located at the sacral parasympathetic nucleus and the intermediolateral nucleus. In addition, neurons that primarily innervate the external urethral sphincter and perineal muscles were observed in the ventrolateral portion (Onuf's nucleus). The lumbar-sacral nerve roots were composed of varying nerve tracts, Le., they were typically divided into 1-2 sub-bundles, and the sub-bundles were then divided into 2-3 tiny bundles. There were extensive fibro-connections between the rootlets. CONCLUSION: The urogenital center in Sprague Dawley rats was located in the L6 -S1 segments of the spinal cord, and the rootlets were clearly observed. Therefore, this rat experimental model could be utilized for highly selective anterior/posterior rhizotomy.
文摘Background: Lack of available reference values in a research setting under local conditions can be a drawback for beginners, as the accuracy of data from control samples cannot be checked at the beginning of a research project. This affects comparisons with data from test samples. To avoid these complications in their research projects,beginners tend to have a greater number of animals in the control group compared to test groups in order to have control group measurements within 2 SDs of the mean.Methods: As non-availability of reference values was a long-felt need, the described project was conducted in order to establish a reference database for selected haematological, biochemical and physiological parameters using apparently healthy Sprague-Dawley rats bred in the Animal House of Faculty of Medicine, University of Colombo(UCFM).Results: Differences in mean values of packed cell volume(PCV), mean corpuscular volume(MCV) and mean corpuscular hemoglobin concentration(MCHC), serum creatinine and blood glucose levels between the two genders were statistically significant. Lipid profile measurements did not differ significantly between genders, but mean and median values of triglycerides(TG) between male and female rats showed a difference of more than 10 mg/dL. The liver enzymes alkaline phosphatase(AP)and aspartate aminotransferase(AST) were also statistically significantly different between sexes. Despite wide variation in mean alanine aminotransferase(ALT)between sexes, the difference was not statistically significant.Conclusion: The findings of this project should support to a certain extent the"Reduction" aspect of the 3 Rs concept of Russell and Burch by reducing the number of Sprague-Dawley rats used in future research projects at UCFM.
文摘AIM: To further clarify the changes occurred in the testicular capsulotomized rats. METHODS: In testicular capsulotomized and sham-operated rats, the cross sectional area, the nucleus diameter and the number of Leydig cells were morphologically analyzed by the Vidas Image Processing System connected to a microscope. RESULTS: In the capsulotomized animals, the cross sectional area of Leydig cells was gradually increased from 30 days onwards. There was no obvious change in the nucleus diameter of Leydig cells. However, The Leydig cell number was significantly increased from day 30 onwards. CONCLUSION: In rats, testicular capsulotomy may induce hyperplasia/hypertrophy of Leydig cells in the testis.
文摘The use of plant parts (leaves, flowers, stems, barks, roots etc.) in traditional medicine is increasingly gaining ground in modern medicine, as plant sources have long been recognized as sources of secondary metabolites which can be used to treat a wide range of diseases. The effect of extracts of Justicia secunda leaves on red blood cells (RBC) count and haemoglobin (Hb) concentration was investigated in adult Sprague-Dawley rats to establish haematinic activity. Phenylhydrazine (PHZ)-induced anaemic rats were treated with water, methanol or ethyl acetate extracts at 200 mg/kg body weight. RBC counts and Hb concentration were analysed using a haematology analyser at 3-day intervals for 21 days. The extracts were compared with rats administered the haematinic tonic Feroglobin®?and vehicle-treated (normal saline). Rats administered the water extract exhibited the most significant increase (P ) in the number of RBCs and Hb concentration compared with the vehicle-treated PHZ-induced anaemic rats. Rats administered the methanol extract followed with significant increase (P ) in RBC counts and Hb concentration (J. secunda leaves has excellent haematinic properties and this provides the pharmacological basis of its use in Ghanaian traditional medicine for the treatment of anaemia.
文摘ATP was added to the cultured sensory neurons obtained from the dorsal root ganglia of the neonatal rats and PBS was added to serve as control. MTT assays were conducted to evaluate the survival and activity of the cultured neurons. And the silicone regenerative chamber was used after the sciatic nerve incision of the mature SD rat. 1 mmol/L ATP was injected into the left chamber and 0.09 % natrium chloride was injected into the right chamber as controls. The changes of nitric oxide synthase (NOS) activity in the corresponding dorsal root ganglia were measured histochemically and image analysis was also performed 4 days after the sciatic nerve injury. The results showed that extracellular ATP could enhance the survival of the neurons and the number of NOS positive neurons were significantly different between the ATP and control groups ( P <0.05). It was suggested that extracellular ATP had neurotrophic effect on neurons survival and could inhibit the NOS activity of the sensory neurons after the peripheral nerve incision, hence exerting the protective effect on the neurons, which was valuable for nerve regeneration after nerve injury.
基金funded by the National Natural Science Foundation of China,No.30672096
文摘The posterior rootlets in L6 and S1 spinal cord of adult male Sprague-Dawley rats underwent electrostimulation. The bladder pressure, urethral perfusion pressure and intracavernous pressure were recorded. When some posterior rootlets of L6 and Sl were electrostimulated, the intracavernous pressure peaked rapidly, but the bladder pressure and the urethral perfusion pressure curve did not show great change. When other rootlets were stimulated, the bladder pressure changed greatly, but the urethral perfusion pressure and the intracavernous pressure did not show great change. When different rootlets were stimulated, the urethral perfusion pressure changed maximally, but there were no great changes in bladder pressure or intracavernous pressure. Furthermore, stimulation of some rootlets produced simultaneous changes in two or three different pressure measures mentioned above. The results demonstrate that regulation by L6 and S1 posterior rootlets of the rat bladder detrusor, external urethral sphincter and penis cavernous body are significantly distinct. Different rootlets can be distinguished by electrostimulation.
基金supported by the National Key Technology R&D Program(No.2012BAK01B00)
文摘Objective To evaluate the combined subchronic toxicity of bisphenol A(BPA) and dibutyl phthalate(DBP) in male Sprague Dawley(SD) rats.Methods Forty 4‐week‐old male rats weighing 115‐125 g were randomly divided into BPA‐treated,DBP‐treated group,BPA+DBP‐treated and control groups and fed with a soy‐ and alfalfa‐free diet containing 285.4 ppm BPA,285.4 ppm DBP,285.4 ppm BPA plus 285.4 ppm DBP,and a control diet,respectively,for 90 consecutive days.At the end of the study,the animals were sacrificed by exsanguination via the carotid artery under diethyl etherane aesthesia and weighed.Organs,including liver,kidneys,spleen,thymus,heart,brain,and testis underwent pathological examination.The androgen receptor(AR),gonadotropin‐releasing hormone receptor(GNRHR),and progesterone hormone receptor(PR) genes from the hypothalamus were detected by real‐time PCR.The biomedical parameters were analyzed.Results No significant difference was found in food intake,body weight,tissue weight,organ/brain weight ratio,and biomedical parameters among the four groups(P〉0.05).However,BPA and DBP up‐regulated AR,PR and GNRHR expression levels in rats and showed a synergistic or an additive effect in the BPA+DBP group.Conclusion The combined subchronic toxicity of BPA and DBP is synergistic or additive in male SD rats.
文摘Experimental models have allowed inquiry into the pathophysiology of varicocele (VC) beyond that possible with human patients. A randomized controlled study in rats was designed to clarify the influence of the degree of left renal vein constriction on the development of adolescent VC. Fifty adolescent male Sprague-Dawley rats (Rattus norvegicus) were randomly assigned to five groups of 10: the experimental groups (I-IV) underwent partial ligation of left renal veins with 0.5-, 0.6-, 0.7-, and 0.8-mm diameter needles, respectively. The control group (V) underwent a sham operation. The diameter of the left spermatic vein (LSV) was measured at baseline and 30 days postoperatively. In addition, the lesion of the left kidney was examined with the naked eye and assessed by Masson's trichrome staining. VC was successfully induced in 2 (20%), 4 (40%), 7 (70%), and 10 (100%) rats in groups I-IV, respectively. The other rats failed to develop VCs primarily due to left renal atrophy. No VC was observed in group V. The postsurgical LSV diameters in VC rats in groups III and IV were 1.54 ± 0. 16 and 1.49 ± 0.13 mm, respectively (P〉 0.05), and their increments were 1.36±0. 10 and 1.31±0. 10 ram, respectively (P 〉 0.05). These results suggest that suitable constriction of the left renal vein is critical for adolescent VC development. In addition, the 0.8-mm diameter needle may be more suitable for inducing left renal vein constriction in adolescent rat models.
基金supported by Fundamental Research Grant Scheme(FRGS)(Grant Number:R/FRGS/A07.00/00710A/002/2016/000374)
文摘Objective: To investigate the wound-healing effect of Alocasia longiloba(A. longiloba) petiole extract on wounds in rats.Methods: Twenty-two male Sprague-dawley rats were randomly assigned to receive 10% solcoseryl gel, phosphate buffer saline, 50% ethanol, 95% ethanol and hexane extracts of A. longiloba at 1.5%, 3% and 6% doses, respectively. A full thicknesses wound(6 mm) was created on the dorsal of the rat; and all rats were applied with the extract solutions, 10% solcoseryl gel and phosphate buffer saline once a day topically until day 12. The wound was photographed on day 1, 6 and 12, and the percentage of wound contraction was calculated. On day 12, rats were sacrificed and histological examination of granulation tissue was carried out using haematoxylin & eosin and Masson's Trichrome stain to determine the wound healing effect.Results: In this study, 6% of 50% and 95% ethanol extracts of A. longiloba showed 82.50% and 82.32% wound contraction, respectively, and were comparable with 10% solcoseryl gel(82.30%). Meanwhile, phosphate buffer saline treated group showed the lowest wound contraction(69.86%). Histological assessment of wound treated with 6% of 95% ethanol extract of A. longiloba showed distinct epidermal and dermal layer, higher proliferation of fibroblast and more angiogenesis with collagen compared to other wound treated groups.Conclusions: A. longiloba petiole extracts have a wound healing potential and 6% of 95% ethanol extract of A. longiloba is more effective. Further studies are required to understand the wound healing mechanism of action of the extract.
文摘This study was carried out to find out if alligator pepper can prevent the development of fetal macrosomia in Sprague-Dawley rats fed with high glycemic index diet. Fifteen adult female Sprague-Dawley rats of proven fertility were acclimatized for a period of two weeks in a well-ventilated laboratory and fed with grower’s mash and water ad libitum. Thereafter, they were randomly placed in separate cages after which a male Sprague-Dawley rat of proven fertility was introduced into each of the cages containing the female rats. They were left in the cages for three days during, which mating was confirmed to have occurred. The male rats were then withdrawn from the female rats, which were placed in separate maternity cages. The female rats were randomly allocated to three groups A, B and C so there were 5 pregnant rats in each group. The rats in group A were fed with 50 g of grower’s mash daily while the rats in groups B and C were fed with 50 g of cooked fermented cassava respectively. All rats were given water ad libitum throughout the duration of the experiment. The rats in groups A and B were intraperitoneally injected with 13.3 ml per Kg body weight of distilled water while the rats in group C were intraperitoneally injected with 13.3 mg/Kg body weight of aqueous extract of alligator pepper respectively. They were observed for 18 - 25 days. The litters of the rats in group B had a significantly higher mean weight than the rats in group A while the litters of the rats in group C had a significantly lower mean weight than the rats in groups B. It was concluded that intraperitoneally injected aqueous extract of alligator pepper, in the first trimester of pregnancy, can prevent the development of fetal macrosomia in Sprague-Dawley rats.
文摘Objective To investigate the effects of different electromagnetic fields on some haematochemical parameters of circadian rhythms in Sprague-Dawley rats. Methods The study was carried out in 18 male and 18 female rats in good health conditions exposed to 50 Hz magnetic sinusoid fields at the intensity of 1000 μT, 100 μT, and 0 μT (control group) respectively, and in 18 male and 18 female rats in good health conditions exposed to 1.8 GHz electromagnetic fields at the intensity of 50 V/m, 25 V/m and 0 V/m (control group), respectively. Following haematochemical parameters for glucose, triglycerides, and total cholesterol were measured. Results Different effects of electromagnetic fields on circadian rhythms of both male and female rats were observed. Different changes occurred in some haematochemical parameters for glucose, triglycerides, and total cholesterol (P〈0.05). Conclusion Exposure to different electromagnetic fields is responsible for the variations of some haematochemical parameters in rats.