Acetylcholine participates in pain modulation by influencing endogenous opiate peptides in rat spinal cord

The spinal cord is a necessary pathway that transfers the body nociceptive inputs to the brain, and endo-genous opiate peptides (EOP) play an important role in pain modulation. Our previous work has proven that arginine vasopressin (AVP) antinociception in the caudate nucleus (CdN) relates with the acetylcholine (Ach) system mainly. The communication was de-signed to investigate the interrelations between Ach system and EOP system at the spinal level during pain process. The results showed that: 1) pain stimulation increased L-enkephalin (L-Ek), β-endorphin (β-Ep), dynorphin A1-13(DynA1-13), Ach and choline (Ch, an Ach metabolic product) concentrations in the spinal cord;2) Ach increased L-Ek, β-Ep and DynA1-13 concentrations in the spinal cord;and 3) Atropine (M-receptor inhibitor) or hexahydric gallamine (N-receptor inhibitor) decreased L-Ek, β-Ep and DynA1-13 concentrations in the spinal cord. The data suggested that Ach antinociception was involved in the EOP system at the spinal level.

Serotonin Influences the Endogenous Opiate Peptides in the Rat Spinal Cord to Participates in Pain Modulation

Spinal cord is a necessary pathway that transfers the body nociceptive inputs to the brain. Endogenous opiate peptides have been proven to participate in the nociceptive process at spinal level. It has reported that serotonin (5-HT, 5-hydroxytryptamine) in spinal cord plays a role in pan modulation, which can be blocked by opiate receptor antagonists. The present study was designed to investigate the interaction between 5-HT and endogenous opiate peptides at rat spinal level effecting on pain modulation. The results showed that 1) pain stimulation increased not only leucine-enkephalin (L-Ek), β-endorphin (β-Ep) and dynorphin A1-13 (DynA1-13) concentrations but also 5-HT and 5-hydorxyindoleace acid (5-HIAA, the 5-HT main metabolic product) concentrations in spinal cord significantly;2) 5-HT could increase L-Ek, β-Ep and DynA1-13 concentrations in spinal cord in a dose-dependent manner, whereas cypotolamine (a 5-HT receptor antagonist) decreased L-Ek, β-Ep and DynA1-13 concentrations in spinal cord. The data suggested that 5-HT antinociceptive role might be involved in the endogenous opiate peptide system through 5-HT receptors at spinal level.

Effect of amitriptyline on gastrointestinal function and brain-gut peptides: A double-blind trial

AIM: To study the effects of low-dose amitriptyline (AMT) on gastrointestinal function and brain-gut peptides in healthy Chinese volunteers. METHODS: This was a double-blind, randomised, placebo-controlled, two-period cross-over trial. Twentyeight healthy volunteers were randomised and administered 1-wk treatments of AMT (12.5 mg tid) or placebo. Before and during the final two days of treatment, gastric emptying, proximal gastric accommodation and visceral sensitivity were measured by drinkingultrasonography test; the orocecal transit time (OCTT) was measured by lactulose hydrogen breath test, and fasting blood was collected. Plasma levels of ghrelin, motilin and neuropeptide Y (NPY) were measured by enzyme-linked immunosorbent assay kits.RESULTS: AMT slowed the OCTT (109.2 ± 29.68 min vs 96.61 ± 23.9 min, P = 0.004) but did not affect liquid gastric emptying and had no effect on proximal gastric accommodation. AMT resulted in decreases in the visual analogue scale (VAS) for difficulty in drinking 600 and 800 mL of water (3.57 ± 0.94 vs 2.98 ± 0.85, 5.57 ± 0.82 vs 4.57 ± 0.98, P < 0.01 for both), although it had no significant effect on the VAS for difficulty in drinking 200 mL and 400 mL of water. AMT significantly increased the plasma ghrelin level (442.87 ± 176.79 pg/mL vs 526.87 ± 158.44 pg/mL, P = 0.04) and the neuropeptide-Y level (890.15 ± 131.46 pg/mL vs 965.64 ± 165.63 pg/mL, P = 0.03), whereas it had no effect on the MTL level. CONCLUSION: Low-dose AMT could slow OCTT, make the stomach less sensitive and increase the plasma levels of ghrelin and NPY. Thus, we recommend the use of low-dose AMT for functional gastrointestinal disorders.

Study on the regulation of brain-gut peptide by Shenling Baizhu San in functional diarrhea rats

Objective:To explore the therapeutic mechanism of Shenling Baizhu San (SLBZS) on functional diarrhea (FDr) by studying the brain-gut axis and related neuropeptides.Methods:Sixty male Wistar rats were randomly divided into the control group,model group,SLBZS-treated group and Montmorillonite Powder-treated group (MP-treated group) (n =15/group).Rats received gavage after the establishment of functional diarrhea.An equal volume of SLBZS solution and Montmorillonite Powder (MP) solution was administered to the SLBZS-treated group and MP-treated group,respectively,and an equal volume of distilled water was administered to the control group and the model group.The chemical components and targets related to SLBZS were identified from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) and Traditional Chinese Medicine Integrated Database (TCMID).The effective chemical components were screened based on oral bioavailability (OB) and drug like-index (DL),and their biological functions were analyzed by GlueGO.Based on this screening,the expression of Cholecystokinin (CCK) and Ghrelin in the hypothalamus of rats was detected by real-time PCR (RT-PCR) and western blotting.Results:In this study,72 effective components and 190 core targets of SLBZS were screened.SLBZS may regulate smooth muscle contraction,energy metabolism and other biological processes.The results of RT-PCR showed that in the model group,the expression of CCK mRNA (P =.001) and Ghrelin mRNA (P =.000) increased significantly.Compared with the model group,CCK mRNA (P =.007) and Ghrelin mRNA (P =.001) levels in SLBZS-treated rats were decreased significantly.The results of western blotting showed that in the model group,the protein expression of CCK (P =.001) and Ghrelin (P =.000) increased significantly.The protein levels of CCK (P =.001) and Ghrelin (P =.005) in the SLBZS-treated group were decreased significantly compared with the model group.Conclusion:SLBZS improved functional diarrhea by regulating the brain-gut axis.Changes in the expressions of brain-gut peptide,CCK and Ghrelin might explain the pathogenesis of functional diarrhea related to brain-gut peptide and gastrointestinal hormone.

Therapeutic effect of zhuodu theory on ulcerative colitis and its effect on brain-gut peptide in serum and inflammatory factor

Objective:To investigate the therapeutic effect of traditional Chinese medicine xiezhuojiedu decoction on ulcerative colitis(UC)based on zhuodu theory and its effect on serum brain-gut peptide and inflammatory factors.Methods:110 cases of UC patients were divided into 2 groups according to the random number table method,with 55 cases in each group.The control group was treated with mesalazine,and the treatment group was given oral administration of Chinese medicine xiezhuojiedu decoction on the basis of the control group.Both groups received continuous treatment for 8 weeks.Integral of TCM syndromes,serum inflammatory factor and brain-gut peptide before and after treatment were compared between the two groups.The clinical efficiency,mucosal healing rate and endoscopic response rate of the two groups were compared.Results:After treatment,Integral of the main TCM syndromes abdominal pain,diarrhea,abdominal distention,mucous hematochezia,tenesmus of the treatment group were lower than the control group(P<0.01),the levels of serum(Tumor necrosis factor-α,(TNF-α),Interleukin(IL)-33,Substance P(SP)were lower than the control group(P<0.01),the levels of IL-10,vasoactive intestinal peptide(VIP),Somatostatin(SS)were higher than the control group(P<0.01),the clinical efficiency and mucosal healing rate were higher than control group(P<0.05),The difference was statistically significant.Conclusion:Based on the zhuodu theory,the xiezhuojiedu decoction can effectively regulate the levels of inflammatory factor and brain-gut peptide in the treatment of UC,improve the symptoms of patients,and promote the repair of intestinal mucosa.It's effective in treatment.

Effects of Pyridoxine on Selected Appetite Regulating Peptides mRNA Expression in Hypothalamic PVN/ARC Nuclei and Gastrointestinal Tract Tissues

An experiment was conducted to investigate the effect of dietary pyridoxine on the gene expression of appetite-regulating peptides in the hypothalamus and gastrointestinal tract of rabbits. Thirty-two rabbits were randomly divided into 2 treatments for 8 weeks (16 replicates/group and 1 rabbit/replicate). The treatments were fed a basal diet (control, measured pyridoxine content is 4.51 mg/kg) and the basal diet with a pyridoxine supplementation at 10 mg/kg (pyridoxine, measured pyridoxine content is 14.64 mg/kg). The results showed that dietary pyridoxine did not significantly alter the mRNA levels of neuropeptide Y, agouti related peptide, pro-opiomelanocortin and cocaine, amphetamine regulated transcript, peptide YY and cholecystokinin in arcuate nucleus, peptide YY in jejunum and ileum, and cholecystokinin in duodenum, jejunum and ileum (P > 0.05). Compared with the control, the mRNA levels of corticotropin-releasing hormone and melanocortin 4 receptor in paraventricular nuclei and peptide YY in duodenum were significantly decreased after pyridoxine treatment (P 0.05). In conclusion, the appetite genes of melanocortin 4 receptor and corticotropin-releasing hormone in paraventricular nuclei and peptide YY in duodenum are involved in the pyridoxine-caused hyperphagia.

Endogenous modulators in the regulation of ion transporting enzymes: structure, function, interactions, recent advancements and future perspectives

A prerequisite for life is the ability to uphold electro-chemical imbalance across biomembranes. Ion trans- porting enzymes, known as specific pumps, are re-sponsible for the transport of various ions across cell membranes to sustain the same. In all eukaryotes, the plasma membrane potential and secondary transport systems are maintained by the activity of P-type ion transporting enzymes, commonly known as ATPase membrane pumps. Malfunction of pumps leads to various cell disorders and subsequently diseases like cardiac problems, renal malfunctionings, diabetes, cataract, even cancer. Activities/functions of these pumps are regulated either by exogenous agents or by endogenous substances like proteins, peptides, hormones, etc., which are collectively known as mo- dulators. Some of these endogenous modulators may be useful for developing drugs depending on the na-ture of regulation. For more than last two decades, researchers across the globe are exploring the me- chanism of action of different endogenous modulators on these ion transporting enzymes with the aim of developing target-specific drugs. In this review, we have discussed recent advances in our understanding of ATPase pumps, e.g., Ca2+-, Na+, K+-, Ca2+, Mg2+-, H+, K+-ATPases, with the emphasis on their functional regulation by a number of endogenous modulators, and the implications of development of some of these modulators as potential drugs.

ENDOGENOUS EXPRESSION AND HLA STABILIZATION ASSAY OF PLASMODIUM FALCIPARUM CTL EPITOPE MINIGENE IN HUMAN HLA- A2.1 AND HLA- B51 CELLS

To evaluate the Plasmodium falciparum CTL epitope vaccines in HLA class I allele specific human cell lines that have high frequency among Chinese population. Methods. Synthesized oligonucleotides encoding for P.f. CTL epitope genes, constructed eukaryotic expression plasmids, transfected the minigenes into HLA class I allele specific human cell lines and identified endogenous expressing of the minigenes by RT- PCR and HLA stabilization assay. Results. Two mini- genes encoding Plasmodium falciparum CTL epitopes were designed and cloned, respectively, into an eukaryotic expressing vector to form TR26 which was restricted to HLA- B51, SH6 which was restricted to HLA- A2.1, and TS, which had the two aforementioned mini- genes fused in tandem. All of these CTL epitope genes were transfected and endogenously expressed in respective cell lines containing appropriate HLA molecules. The obviously increased expressions of HLA class I molecules were detected in the transfected cell lines. It was demonstrated that the two discrete Plasmodium falciparum epitope genes were effectively processed and presented, and the close proximity of the two epitope genes in one chain as in mini- gene TS did not interfere with the processing and presenting of each epitope gene in corresponding cell line. Conclusion. A successful expression and presentation of multiple CTL epitope mini- gene in MHC class I allele specific human cell lines were demonstrated by an in vitro assay, which could be corresponding to the vaccination of CTL vaccines in people with different MHC I molecules. This work also suggested the possibility of constructing a multiple CTL epitope plasmodium falciparum DNA vaccine that could cover most of Chinese population.

Reduced endogenous insulin secretion in diabetic patients with low-titer positive antibodies against GAD

Aim: To investigate the clinical characteristics of diabetic patients with a low-titer positive for the anti-glutamic acid decarboxylase 65 antibody (GAD antibody). Methods: The subjects were 420 diabetic inpatients. The endogenous insulin secretion was estimated on the basis of the C-peptide immunoreactivity from a 24 h urine collection (uCPR). Clinical variables were compared between patients negative for the GAD antibody (GAD antibody titer < 1.5 U/mL), a low-titer positive GAD antibody (1.5 U/mL ≤ GAD antibody titer < 10 U/mL) and a high-titer positive GAD antibody (10 U/mL ≤ GAD antibody titer). Results: The low and high-titer positive GAD antibodies were found in 25 and 10 patients, respectively. The uCPR was significantly lower in both the patients with a low (37 ± 33 ug/24h) and high-titer (39 ± 27 ug/24h) positive GAD antibodies than in those negative for GAD antibodies (71 ± 52 ug/24h). The uCPR level was significantly lower in the low-titer positive GAD antibody group (29 ± 22 ug/24h) than in the negative group (67 ± 55 ug/24h) among the patients not taking insulin secretagogues. The difference disappeared in the subjects taking insulin secreagogues. In the stepwise multiple regression analysis, a low-titer positive GAD antibody was independently associated with the uCPR level. Conclusions: Endogenous insulin secretion is reduced in diabetic patients positive for GAD antibodies, even if the titer is low. Earlier initiation of insulin therapy might therefore protect the pancreatic β-cell function in diabetic patients with a low-titer positive GAD antibody.

干腌火腿抗氧化肽的研究进展

自由基过量累积会导致人体许多慢性疾病的产生,如衰老、慢性炎症、心血管疾病等,目前常规的解决方法是使用抗氧化剂。然而人工合成的抗氧化剂对人体有潜在危害,因此无毒副作用的抗氧化肽成为了当今研究的热点。作为发酵肉制品之一的干腌火腿,因其蛋白质含量丰富,且在发酵过程中受到内源酶和微生物的影响,会对蛋白质进行分解,从而产生具有抗氧化活性的小肽。大量的研究表明,来源于干腌火腿的肽具有极强的抗氧化活性。因此,干腌火腿作为天然抗氧化肽的潜在来源,备受研究人员的关注。本文综述了干腌火腿中抗氧化肽研究的最新进展,主要包括抗氧化肽的形成、制备、纯化鉴定及抗氧化机制4个方面,其中特别指出外源微生物对抗氧化肽形成的影响,以期为干腌火腿抗氧化肽的进一步研究提供理论基础。

An auxin‐responsive endogenous peptide regulates root development in Arabidopsis

Auxin plays critical roles in root formation and development. The components involved in this process, however, are not well understood. Here, we newly identified a peptide encoding gene, auxin-responsive endogenous polypeptide 1 （AREP1）, which is induced by auxin, and mediates root development in Arabidopsis. Expression of AREP1 was specific to the cotyledon and to root and shoot meristem tissues. Amounts of AREP1 transcripts and AREP1-green fluorescent protein fusion proteins were elevated in response to indoleacetic acid treatment. Suppression of AREP1 through RNAi silencing resulted in reduction of primary root length, increase of lateral root number, and expansion of adventitious roots, compared to the observations in wild-type plants in the presence of auxin. By contrast, transgenic plants overexpressing AREP1 showed enhanced growth of the primary root under auxin treatment. Additionally, rootmorphology, including lateral root number and adventitious roots, differed greatly between transgenic and wildtype plants. Further analysis indicated that the expression of auxin-responsive genes, such as IAA3, IAA7, IAA17, GH3.2, GH3.3, and SAUR-AC1, was significantly higher in AREP1 RNAi plants, and was slightly lower in AREP1 overexpressing plants than in wildtype plants. These results suggest that the novel endogenous peptide AREP1 plays an important role in the process of auxinmediated root development.

Comprehensive analysis of the N and C terminus of endogenous serum peptides reveals a highly conserved cleavage site pattern derived from proteolytic enzymes

The human serum proteome is closely associated with the state of the body.Endogenous peptides derived from proteolytic enzymes cleaving on serum proteins are widely studied due to their potential application in disease-specific marker discovery.However,the reproducibility of peptidome analysis of endogenous peptides is significantly influenced by the proteolytic enzymes within body fluids,thereby limiting the clinical use of the endogenous peptides.We comprehensively investigated the N and C terminus of endogenous peptides using peptidomics.The cleavage site patterns of the N and C terminus and adjacent sites from all the identified endogenous peptides were highly conserved under different sample preparation conditions,including long-term incubation at 37℃ and pretreatment with repeated freeze-thaw cycles.Furthermore,a distinguishable cleavage site pattern was obtained when a different disease serum was analyzed.The conserved cleavage site pattern derived from proteolytic enzymes holds potential in highly specific disease diagnosis.

Application progress of Chinese medicine in the treatment of irritable bowel syndrome based on the brain-gut axis theory

Irritable bowel syndrome is one of the most common functional gastrointestinal diseases,with a global prevalence of about 12%[1].Modern studies have shown that the abnormality of brain-gut peptides is closely related to the occurrence of irritable bowel syndrome.This article starts with vasoactive intestinal peptide,substance P,serotonin,neuropeptide Y,corticotropin releasing factor,calcitonin gene-related peptide,cholecystokinin and other brain-gut peptides and their correlation with intestinal flora,to summarize the treatment of irritable bowel syndrome with traditional Chinese medicine in recent years.

Effect of Xiaoyao San on the brain-gut axis in rats after chronic immobilization stress

Objective:To investigate the effect of Xiaoyao San on the brain-gut axis in rats exposed to chronic immobilization stress (ClS).Methods:Rats were divided into control,model,and treatment groups.The rats belonging to the model and treatment groups were subjected to CIS for 21 consecutive days,during which they were administered Xiaoyao San decoction [3.854 g/(kg· d)] or vehicle by gavage,and their body weight gain,food intake and water intake were monitored.The rats were subsequently subjected to the open field test (OFT) and D-XyloSe absorption test,and the expression levels of neuropeptides secreted by the hypothalamus and stomach were determined by enzyme-linked immunosorbent assay (ELISA),radioimmune analysis,or real-time fluorescence quantitative polymerase chain reaction.Gastric mucosal morphology was also assessed.Results:The model rats exhibited complex brain-gut axis abnormalities following exposure to CIS,abnormalities signified by decreases in food intake,reductions in digestive absorption,decreases in body weight,decreases in the total distances traveled and increases in the time in the central zone during the OFT,gastric mucosal lesion development and decreases in gastrointestinal hormone secretion.These changes were reversed after treatment with Xiaoyao San,which also regulated the secretion of both peripheral (serum and stomach) and central (hypothalamus) brain-gut peptides.Specifically,the levels of neuropeptide Y (NPY) and neuropeptide Y receptor Y5,which are secreted by the hypothalamus and promote digestive function,were increased in the Xiaoyao San-treated group compared with the model group.Furthermore,the levels of pro-opiomelanocortin (POMC) and its receptor,melanocortin-4 receptor (MC4R),which are secreted by the hypothalamus and inhibit digestive function,were significantly decreased in the treatment group compared with the model group.However,the levels of ghrelin (GHRL),gastrin (GAS) and motilin (MTL),which are secreted by the stomach,were significantly increased in the serum and stomach of the treatment group compared with the serum and stomach of the model group following Xiaoyao San treatment (P <.05 vs.the model group).Conclusion:Xiaoyao San attenuates CIS-induced gastrointestinal dysregulation by regulating the peptides secreted by both the hypothalamus and the gastrointestinal tract (GIT),suggesting that its effects are associated with the brain-gut axis.

视网膜内源性多肽CKASKGKL调节p53/cyclinD1信号通路拮抗多氯联苯暴露致子代视网膜损伤

目的:探讨视网膜内源性多肽CKASKGKL对多氯联苯(PCBs)暴露致子代视网膜发育异常的拮抗作用及可能的作用机制。方法:以斑马鱼为模式动物,收集斑马鱼胚胎予以PCBs处理,同时给予多肽CKASKGKL进行挽救实验,收集受精后48h幼鱼制备石蜡切片,显微镜下观察各组子代斑马鱼视网膜发育情况。以大鼠视网膜神经节细胞(RGC)为工具细胞,予以PCBs处理,同时给予多肽CKASKGKL进行挽救实验,CCK-8检测各组细胞增殖活性;采用基因富集分析(GSEA)了解多肽CKASKGKL可能作用的信号通路,Western blotting初步验证多肽CKASKGKL对视网膜神经节细胞p53/cyclinD1信号通路的影响。结果:多肽CKASKGKL可以拮抗PCBs暴露致子代斑马鱼视网膜发育异常,可以拮抗PCBs暴露致视网膜神经节细胞增殖活性降低;GSEA结果显示,多肽CKASKGKL可能通过参与p53信号通路发挥作用;Western blotting检测显示,多肽CKASKGKL干预后,视网膜神经节细胞中p53表达降低,其下游负调控基因cyclinD1表达增高。结论:多肽CKASKGKL可以拮抗PCBs暴露导致的子代视网膜损伤,可能与其通过调节p53/cyclinD1信号通路而促进细胞增殖有关。

内源性多肽ECDP4对子宫内膜癌肿瘤微环境中淋巴细胞分群影响的实验研究

目的探讨内源性多肽ECDP4在人外周血单核细胞(PBMCs)和子宫内膜癌Ishikawa细胞共培养体系下对PBMCs中T淋巴细胞亚群比例的影响。方法收集2020年9月至2020年11月手术切除的3例子宫内膜癌和3例配对正常子宫内膜组织标本。使用在线数据库UniProt、ProteomicsDB、MaxQB、UniProt和The Human Protein Atlas分析多肽ECDP4的前体蛋白及其生物学功能。建立人子宫内膜癌Ishikawa细胞株和新鲜人PBMCs共培养模型,分为对照组(含5%胎牛血清培养基)和实验组(含5%胎牛血清培养基中加100 ng/L内源性多肽ECDP4),共培养96 h,收集PBMCs。用流式细胞术分析PBMCs中淋巴细胞亚群比例变化。结果在正常子宫内膜组织中,ECDP4表达量为7.33×10-4±1.13×10-4,而在子宫内膜癌组织中表达量为7.30×10^(-5)±8.47×10^(-6)(P=0.0016)。生物信息学分析显示,NOVA2是ECDP4的前体蛋白,但其并不是子宫内膜癌的预后因素。流式细胞术检测显示,相较于单纯培养PBMCs,共培养体系中CD4^(+)T淋巴细胞比例下调(51.31±11.05)%(P<0.001),CD8^(+)T淋巴细胞比例下调(52.98±5.86)%(P<0.001)。相较于对照组,在共培养体系中加入ECDP4后,CD4^(+)T淋巴细胞比例上调(15.58±2.34)%(P<0.001),Ki-67的比例上调(54.60±24.5)%(P=0.0043),干扰素γ(INF-γ)的比例上调(27.92±17.25)%(P=0.0486);CD8^(+)T淋巴细胞比例上调(20.04±6.70)%(P<0.001),Ki-67的比例上调(26.57±6.42)%(P<0.001),INF-γ比例上调(87.48±40.70)%(P=0.01)。结论多肽ECDP4作为NOVA2的降解产物在子宫内膜癌中显著低表达,其能够增加PBMCs中CD4^(+)T淋巴细胞及CD8^(+)T淋巴细胞的比例,促进CD4^(+)及CD8^(+)T淋巴细胞的增殖作用,同时增加INF-γ的分泌量。内源性多肽ECDP4具有进一步应用于临床研究的价值。

内源性阿片肽疼痛调节机制

内源性阿片肽(EOP)作为一类重要的神经递质发挥着许多生物学效应,而在痛觉信息的传递和调节过程中发挥的重要作用最为显著,这些结果将可能为疼痛治疗开辟新天地。本文就近年来EOP的研究进展,特别是关于它们在神经系统内的分布,组成,阿片受体的特点,疼痛调节的特点及其机制等方面作一综述。

电针三阴交穴和血海穴对实验性类痛经大鼠痛调节机制的影响

目的:通过观察电针同一经脉上的同神经节段支配的不同属性穴位对大鼠实验性类痛经反应和中枢痛觉调制系统内阿片肽类物质的影响,探讨经穴效应是否存在特异性。方法:动情间期3月龄SD雌性大鼠64只,随机分为盐水组、模型组、三阴交组、血海组,每组16只。除盐水组外,其余各组大鼠均以苯甲酸雌二醇和缩宫素制备类痛经大鼠模型。模型制备后,给予穴位组即刻电针。随即观察大鼠的扭体反应,并应用免疫组化法和ELISA法分别检测大鼠相应节段脊髓背角浅层κ-受体的表达和PAG内ENK、β-EP的含量。结果:模型制备后,大鼠扭体潜伏期明显缩短,扭体次数和评分明显增加(P<0.01)。电针两穴后,扭体评分和次数均明显减少(P<0.01),且电针三阴交穴扭体潜伏期明显延长(P<0.05);电针三阴交和血海穴可使各节段脊髓背角浅层κ-受体均有明显表达(P<0.05,P<0.01);但电针三阴交穴的L2、S1节段IOD值比血海穴明显升高(P<0.01,P<0.05);电针三阴交穴可使PAG内ENK和β-EP(P<0.01)含量明显升高。结论:电针同一经脉上的同神经节段支配的不同属性穴位均可缓解大鼠的类痛经反应,并可调节中枢痛觉调制系统内的阿片肽类物质的含量。但穴位属性不同。调节效应不同。特定穴的调节效应优于非特定穴。说明经穴效应具有相对特异性。

干腌火腿中肽的形成机理研究进展

干腌火腿加工过程中,在肌肉中内源酶和微生物的共同作用下,产生多种具有特定生物活性或对产品风味具有提升作用的肽。抗氧化肽、降血压肽和抗菌肽等生物活性肽提升火腿的营养价值;呈味肽如鲜味肽、甜味肽、苦味肽、酸味肽、咸味肽及浓厚感肽,有助于形成火腿独特的风味。该文综述了干腌火腿中肽的功能特性,重点对加工过程中肽的影响因素及形成机理进行介绍,为干腌火腿品质特性提升和新工艺设计提供理论参考依据。

内源性阿片肽在正常妊娠和分娩中的变化

目的 :观察内源性阿片肽在正常妊娠及分娩各阶段含量的变化规律。 方法 :采用神经肽放射免疫测定方法 ,测定5 0例正常未孕妇女 (对照组 )、4 5例正常妊娠妇女 (早孕、中孕及晚孕 3个时间段 )、4 5例正常平产妇女 (潜伏期、活跃期及分娩即刻 3个时间段 )和 4 5例产后妇女 (2h、2 4h 2个时间点 )血浆中 3种内源性阿片肽 (β 内啡肽、强啡肽A1 13 及亮啡肽 )含量的变化。 结果 :妊娠、分娩不同阶段 ,血浆中 3种内源性阿片肽含量均有不同程度的变化 ;β 内啡肽含量在妊娠期略有上升 ,分娩期开始显著增高 ,至分娩即刻升到最高 ,升高程度是 3种肽中最高的且产后 2 4h降至正常 ;强啡肽A1 13 含量从晚期妊娠开始显著升高 ,并上升至分娩即刻 ,分娩后渐下降 ,整个变化趋势平稳 ;亮啡肽含量在早孕时显著升高 ,而中、晚期降至正常 ,直至分娩即刻时再次显著升高 ,产后 2 4h继续上升至最高。 结论 :内源性阿片肽在正常妊娠及分娩各时期有着重要的调节功能。