Genome-edited rabbits:Unleashing the potential of a promising experimental animal model across diverse diseases

Animal models are extensively used in all aspects of biomedical research,with substantial contributions to our understanding of diseases,the development of pharmaceuticals,and the exploration of gene functions.The field of genome modification in rabbits has progressed slowly.However,recent advancements,particularly in CRISPR/Cas9-related technologies,have catalyzed the successful development of various genome-edited rabbit models to mimic diverse diseases,including cardiovascular disorders,immunodeficiencies,agingrelated ailments,neurological diseases,and ophthalmic pathologies.These models hold great promise in advancing biomedical research due to their closer physiological and biochemical resemblance to humans compared to mice.This review aims to summarize the novel gene-editing approaches currently available for rabbits and present the applications and prospects of such models in biomedicine,underscoring their impact and future potential in translational medicine.

Effects of Incorporating Mango (Mangifera indica), Avocado (Persea americana) and Guava (Psidium guajava) Leaves Powder in the Ration on Growth Characteristics in Rabbits

A study conducted on burgundy rabbits evaluated the effects of rations containing mango (Mangifera indica), avocado (Persea americana) and guava (Psidium guajava) powder. For this purpose, 36 rabbits (20 males and 16 females) aged 60 to 70 days with an average weight of 1012 ± 133 g were divided randomly into 4 equal groups (T0, T1, T2 and T3) of 9 animals each according to body weight (bw). The rabbits were divided throughout the trial, the animals were fed, those of group T0 (control) with a standard feed without any type of leaf powder, while those of groups 1, 2 and 3 received the standard feed supplemented with Mangifera indica, Persea americana and Psidium guajava leaves powder at the rate of 0.5% respectively. After two months of treatment, the animals were fasted for 12 hours (20 h - 8 h) and sacrificed to evaluate carcass and digestive organ weights. The results revealed that the values of feed intake, live weight and weight gain were non-significantly (p > 0.05) increased in all animals regardless of the ration in reference to the control. The different leaves powder induced an increase in carcass yield in rabbits but this increase was only significant (p M. indica leaf powder (51.03 ± 0.24) as compared to the control (48.63 ± 0.74). Gut length was significantly increased in animals fed rations containing Psidium guajava and Persea americana leaves powder compared to the control. A significant increase in gut weight was observed in animals fed the Persea americana leaf supplemented ration. In general, mango leaf powder performed better than other types of powders.

Betaine addition to the diet alleviates intestinal injury in growing rabbits during the summer heat through the AAT/mTOR pathway

Background The aim of this experiment was to investigate the effect of different levels of betaine(Bet)inclusion in the diet on the intestinal health of growing rabbits under summer heat.A total of 100 weaned Qixing meat rabbits aged 35 d with body weight of 748.61±38.59 g were randomly divided into 5 treatment groups:control group(basal diet)and Bet groups(basal diet+0.75,1.0,1.5 or 2.0 g/kg Bet).The average daily temperature in the rabbitry during the experiment was 30.48°C and the relative humidity was 69.44%.Results Dietary addition of Bet had no significant effect on growth performance and health status of growing rabbits(P>0.05),but it increased ileal secretory immunoglobulin A content compared to the control under summer heat(P<0.05).Addition of 0.75 g/kg Bet up-regulated jejunal IL-4,down-regulated ileal TNF-αexpression(P<0.05).The addition of 1.0 g/kg Bet increased the villi height(VH)in the jejunum(P<0.05).Serum glucose levels were reduced,and the expression of SLC6A20 was up-regulated in jejunum and ileum of rabbits fed with 1.5 g/kg Bet(P<0.05).When added at 2.0 g/kg,Bet reduced serum HSP70 content,increased jejunal VH,and up-regulated duodenal SLC7A6,SLC38A2,mTOR and 4EBP-2 expression(P<0.05).Correlation analysis revealed that intestinal mTOR expression was significantly and positively correlated with SLC7A6,SLC38A2,SLC36A1 and IL-4 expression(P<0.05).Conclusions Dietary addition of Bet can up-regulate the expression of anti-inflammatory factors through the AAT/mTOR pathway,improve the intestinal immune function,alleviate intestinal damage in growing rabbits caused by summer heat,and improve intestinal health.

An Improved Artificial Rabbits Optimization Algorithm with Chaotic Local Search and Opposition-Based Learning for Engineering Problems and Its Applications in Breast Cancer Problem

Artificial rabbits optimization(ARO)is a recently proposed biology-based optimization algorithm inspired by the detour foraging and random hiding behavior of rabbits in nature.However,for solving optimization problems,the ARO algorithm shows slow convergence speed and can fall into local minima.To overcome these drawbacks,this paper proposes chaotic opposition-based learning ARO(COARO),an improved version of the ARO algorithm that incorporates opposition-based learning(OBL)and chaotic local search(CLS)techniques.By adding OBL to ARO,the convergence speed of the algorithm increases and it explores the search space better.Chaotic maps in CLS provide rapid convergence by scanning the search space efficiently,since their ergodicity and non-repetitive properties.The proposed COARO algorithm has been tested using thirty-three distinct benchmark functions.The outcomes have been compared with the most recent optimization algorithms.Additionally,the COARO algorithm’s problem-solving capabilities have been evaluated using six different engineering design problems and compared with various other algorithms.This study also introduces a binary variant of the continuous COARO algorithm,named BCOARO.The performance of BCOARO was evaluated on the breast cancer dataset.The effectiveness of BCOARO has been compared with different feature selection algorithms.The proposed BCOARO outperforms alternative algorithms,according to the findings obtained for real applications in terms of accuracy performance,and fitness value.Extensive experiments show that the COARO and BCOARO algorithms achieve promising results compared to other metaheuristic algorithms.

The Observation of the Influence of Vasectomy on Some Immunological Functions in Rabbits

To study the functional changes of immunological survcillsnce after vasectomy,we hzve dynamically obscrved the influence of vasectonly on the functions of T lymphocytes and macrophages of peripheral blood from vasectomized animals as the exPerimental model. The results showed that: (1) PHA and Con-A induced mitogenesis of T lymphocytes from the rabbits vasectomized for eight months was significantly inhibited (P<0.01) and recovered in rabbits vasectoomized for 12, 18 and 22 months respectively, (2) The IL -2 secretion from peripheral blood mononuclcar cells (PBMCs) in the rabbits vasectomized for 8 months was reduced remarkably (P<0.01) and reached the normal level in the rabbits vasectomlied for 12 months; (3) A significant correlation was found betwecn Con-A induced mitogenesis of T lymphocytes and the IL-2 secrcted from PBMCs (r=0.661, P<0.01); (4) The IL- 1 secrction form periPhoal blood macrophsges induced by LPS significantly increased in the rabbits vasectonlized for S months (P<0.02) and returned to the normal level in the rabbits vasectomized for 12, 18 and 22 months respectively, (5) The levl of plasma lysozyme increased significantly in the rabbits vasectomized for 8 months (P<0.05) and returned to the normal in the rabbits vasectomized for 12 months, (6) The level of IL- 1 secreted by the macrophages and the level of plasma lysozyme were closely. Correlated (r=0.576, P<0.001). The present results may provide an expeimantal evidence for the evaluating the functional changes of immunological surveillance in vasectomized animals.

Comparison of Soleus Muscle Fibers in Rats and Rabbits at Different Stages of Postnatal Development

In the present study,the effects of postnatal development on the number and distribution of skeletal muscle fibers of different types in hind leg of rat and rabbit were studied.The soleus muscles of rats aged 2 days,2,4,6,8,and 10 weeks (body weight 10,32,95,190,280,and 320 g),and rabbits aged 2 days,2,4,8,12,16,20,and 24 weeks (body weight 100,220,400,750,1 200,1 600,2 100,and 2 500 g) were stained with succinic dehydrogenase.With an image analysis system,the X-Y coordinates of fibers were used to analyze the growth-related changes.The results of present study showed that three types of fibers were found in the soleus muscles of rat and rabbit,i.e.,type Ⅰ (slow oxidative),ⅡX (fast oxidative),and ⅡA (fast oxidative glycolytic).The type Ⅰ fibers were present throughout the muscle that had a uniform distribution and tended to increase in number with aging.Type ⅡX fibers were scattered throughout the muscle and decreased markedly in number with aging.Type ⅡA fibers were located at the central and deep regions,and showed a little or no change in number and distribution with aging.While be of age,type ⅡA and ⅡX fibers became restricted to the superficial region.No type ⅡB fibers were detected.Type ⅡA fibers had the largest diameter,type Ⅰ intermediate and type ⅡX the smallest.Mean cross-sectional area of each type fibers of rabbits was larger than that of rats.The present results indicate that the number and distribution of muscle fibers of different types in hind limb of rat and rabbit change with the process of postnatal growth.

Pharmacokinetics of Junmie for Novel Antibacterial Medicine in Rabbits

[Objective] The paper presents the pharmacokinetics of Junmie in healthy rabbits and thus provides a basis for its rational application. [ Method] HPLC method was developed to detect the concentration of Junmie with benzoyl ciprofloxacin as internal standard. After the healthy rab bits was respectively injected Junmie intravenously and intramuscularly, plasma concentration after injection was detected with the established HPLC method so as to determine the best pharmacokinetic model. [Result] The conditions of HPLC were as follows： mobile phase was 100 ml 60% （V/V） methanol solution （pH 3.0） ; flow rate was 1.0 mVmin; column temperature was （25.0 ±0.5） ℃; detection wavelength was 278 nm. The concentration time data of the plasma, collected from intravenously and intramuscularly injected rabbits, was separately in line with the two com partments and one compartment open model with the first order absorption. The main pharmacokinetic parameters of the plasma sample （ i. v. ） were as below： T1/2= = 0.07 h, T1/2 = 0.82 h, AUC = 3.51 mg/（L . h）, CLB = 4.57 L/（kg . h） ; the plasma sample （i. m. ） ： T1/2 = 0.33 h, T1/2k = 0.33 h, Tp = 0.6 h, Cmax = 2.55 μg/ml, AUC = 4.87 mg/（L . h）. The bioavailability was approximately 110%. [Conclusion] After intra muscular administration, Junmie is absorbed and eliminated quickly with high bioavallability and extensive distribution.

家兔(Oryctolagus cunieulus Rabbits)消化道嗜银细胞的分布和形态学观察

本文应用Grimelius法对家兔 (OryctolaguscunieulusRabbits)消化道嗜银细胞的形态、分布位置及分布密度进行了研究 .实验结果显示 :小肠段嗜银细胞呈梭形具有突起 ,而其它部位多数呈圆形或椭圆形 ;嗜银细胞多分布于粘膜上皮细胞之间或腺泡上皮之间 ;除食管未见嗜银细胞外 ,消化道其它部位均有嗜银细胞的分布 ,密度近似呈字母“M”形 .根据其嗜银细胞形态 ,认为家兔消化道嗜银细胞具有内、外两种分泌方式 .本文还结合家兔的食性。

Effect of peroxisome proliferator-activated receptor gamma agonist on heart of rabbits with acute myocardial ischemia/reperfusion injury

Objective:To explore protective effect of rosiglitazone on myocardial ischemia reperfusion injury.Methods:A total of 48 male SD rats were randomly divided into control group(A),I/R group(B),high dose of rosiglitazone(C),low dose of rosiglitazone(D).Plasm concentration of creatine kinase(CK),CK-MB,hsCRP,Superoxide dismutase(SOD),malondialdehyde(MDA),glutathione peroxidase(GSH-Px),nitric oxide(NO)and endothelin(ET)were measured 1 h later after I/R.24 h after I/R hearts were harvested to observe pathological and ultrastructural changes.Immunohistochemistry and western blotting was used to test CD40 expression in myocardial tissue.Area of myocardial infarction were tested,arrhythmia rate during I/R was recorded.Results:Plasm concentration of creatine kinase(CK),CK-MB,hsCRP,NO,MDA and ET were decreased in group C,D compared with group B.Plasm concentration of T-SOD and GSHPx was increased significantly in group C,D compared with group B.Compared with group B,pathological and ultrastructural changes in group C,D were slightly.Myocardial infarction area and arrhythmia rate were lower in group C,D compare with group B.Conclusions:Rosiglitazone can protect myocardium from I/R injury by enhancing T-SOD and GSH-Px concentration,inhibit inflammatory reaction,improve endothelial function,reduce oxidative stress and calcium overload.

Effect of extracorporeal bioartificial liver support system on fulminant hepatic failure rabbits

AIM To evaluate the possibility of usingcultured human hepatocytes as a bridge betweenbioartificial liver and liver transplantation.METHODS In this experiment,the efficacy ofextracorporeal bioartificial liver support system(EBLSS)consisting of spheriodal human livercells and cultured hepatocytes supernatant wasassessed in vivo using galactosamine inducedrabbit model of fulminant hepatic failure.RESULTS There was no difference of survivalbetween the two groups of rabbits,but in thesupported rabbits serum alanineaminotransferase,total bilirubin and creatininewere significantly lower and hepatocyte necrosiswas markedly milder than those in controlanimals.In addition,a good viability of humanliver cells was noted after the experiment.CONCLUSION EBLSS plays a biologic role inmaintaining and compensating the function ofthe liver.

Effect of vasectomy via inguinal canal on spermatogenesis in rabbits

Aim： To determine whether vasectomy away from the epididymal tail （via the inguinal canal） in rabbits can reduce the early postoperative effects on spermatogenesis. Methods： Twenty-nine normal male Japanese white rabbits （aged 4- 6 months） were subjected to unilateral close-ended （conventional） or open-ended （the cut end of the juxta-epididymal vas deferens not ligated） vasectomy via the inguinal canal. Ten days and 3 months after operation, testes, epididymides and vasa deferentia were removed and methacrylate resin-embedded sections prepared. The histology of the testis, epididymis and vas deferens was examined under light microscope, and the volume and diameter of the seminiferous tubules were quantitatively studied using stereological methods. Results： Neither of the methods of vasectomy led to apparent damage to spermatogenesis on the vasectomized side in comparison with the contralateral shamoperated side, but the juxta-epididymal vas deferens on the vasectomized side was highly distended and contained numerous sperm 3 months after operation. Conclusion： Vasectomy away from the cauda epididymis has no significant early postoperative effects on spermatogenesis in rabbits.

CREATE TRANSGENIC RABBITS BY MICROINJECTING HUMAN apoA-Ⅱ GENE INTO FERTILIZED EGGS

Objective To create transgenic rabbits by microinjecting human apolipoprotein A-Ⅱ (apoA-Ⅱ) gene into one-cell embryos, to study apoA-Ⅱ gene function on plasma lipoprotein metabolism and atherosclerosis. Methods Superovulation and synchronization of estrus were induced in female Japanese White Rabbits by injecting hormone, then mating with male. After collected the fertilized eggs, the human apoA-Ⅱ gene was microinjected into the male pronucleus of eggs. The injected eggs were transferred into recipient female rabbits. Last, extract DNA from the new borns ear and determine whether the newborns were transgenic by polymerase chain reaction (PCR) or Southern blot analysis. Results A total of 822 embryos with microinjection of human apoAⅡ gene were implanted into 28 recipient rabbits. The number of surviving newborns was 37. 3 transgenic positive surviving founders were found with human apoA-Ⅱ.

Effects of 7-methylxanthine on form-deprivation myopia in pigmented rabbits

AIM: To determine the effect of 7-methylxanthine (7-MX) on the posterior sclera of form-deprivation myopia (FDM) in pigmented rabbits. METHODS: Sixteen pigmented rabbits were monocularly deprived (MD) by suturing the right eyelids after natural eye opening (ten-day old) for a period of 30 days. Two groups of pigmented rabbits were fed either 7-MX (30 mg per kg body weight; n=8) or vehicle control (saline equal volume with 7-MX; n=8). Ocular refractions, axial lengths and body weights were measured at the start and the end of the experiment 30 days later. Electron microscopy was used to measure and determine the collagen fibril diameters in the posterior pole of sclera. RESULTS: In vehicle control MD pigmented rabbits, 30 days of MD produced -1.10D+/- 0.78D of myopia and the axial length increased 0.51mm+/- 0.09mm. In MD pigmented rabbits fed with 7-MX, 30 days of MD induced only -0.21D+/- 0.11D of myopia and the axial length increased 0.07mm+/- 0.10mm. There was significant change in axial length of vehicle control MD pigmented rabbits (13.11mm +/- 0.19mm versus 12.60mm+/- 0.06mm; P =0.03). The changes in refraction and axial length of two MD groups' contalateral eyes during the 30 days were not significantly different (2.75D+/- 0.27D versus 2.75D 0.35D, P>0.05; 12.60mm+/- 0.06mm versus 12.45mm +/- 0.14mm, P >0.05). The weights of the two groups pigmented rabbits had no significant changes (187g+/- 22.1g versus 189g+/- 19.3g, P>0.05). The diameter cif scleral collagen fibers increased in both eyes of 7-MX treated pigmented rabbits. There was significant difference in collagen fibril diameters of inner layer (111.34nm+/- 28.30nm versus 94.80nm +/- 27.52nm, P =0.002) and outer layer (167.92nm +/- 55.82nm versus 144.04nm +/- 47.02nm P =0.016) in the posterior sclera between the myopic eyes of vehicle control MD group and contralateral eyes of 7-MX treated MD group. CONCLUSION: 7-MX appears to prevent FDM in pigmented rabbits by remodeling the posterior sclera.

Procyanidin B2 protects against diet-induced obesity and non-alcoholic fatty liver disease via the modulation of the gut microbiota in rabbits

BACKGROUND Procyanidins have beneficial effects on metabolic syndrome and antimicrobial activity,but the mechanisms underlying these effects are unclear.AIM To investigate the effects of procyanidin B2(PB2)on non-alcoholic fatty liver disease and to explore the possible mechanism.METHODS Thirty male New Zealand white rabbits were randomized into three groups.All of them were fed either a high-fat-cholesterol diet(HCD)or chow diet.HCD-fed rabbits were treated with vehicle or PB2 daily for 12 wk.Body weight and food intake were evaluated once a week.Serum biomarkers,such as total cholesterols,triglycerides,and aspartate transaminase,were detected.All rabbits were sacrificed and histological parameters of liver were assessed by hematoxylin and eosin-stained sections.Moreover,several lipogenic genes and gut microbiota(by 16S rRNA sequencing)were investigated to explore the possible mechanism.RESULTS The HCD group had higher body weight,liver index,serum lipid profile,insulin resistance,serum glucose,and hepatic steatosis compared to the CHOW group.PB2 treatment prevented HCD-induced increases in body weight and hypertriglyceridemia in association with triglyceride accumulation in the liver.PB2 also ameliorated low-grade inflammation,which was reflected by serum lipopolysaccharides and improved insulin resistance.In rabbit liver,PB2 prevented the upregulation of steroid response element binding protein 1c and fatty acid synthase and the downregulation of carnitine palmitoyltransferase,compared to the HCD group.Moreover,HCD led to a decrease of Bacteroidetes in gut microbiota.PB2 significantly improved the proportions of Bacteroidetes at the phylum level and Akkermansia at the genus level.CONCLUSION Our results indicate the possible mechanism of PB2 to improve HCD-induced features of metabolic syndrome and provide a new dietary supplement.

Scleral ultrastructure and biomechanical changes in rabbits after negative lens application

AIM： To address the microstructure and biomechanical changes of the sclera of rabbits after negative lens application by spectacle frame apparatus. METHODS： Five New Zealand rabbits of seven weeks post-natal were treated with -8 D lens monocularly over the course of two weeks. Refractive errors and axial length （AXI.） were measured at the 1st, 7th and 14th days of the induction period. Ultrastructure of sclera was determined with electron microscopy. Biomechanical properties were tested by an Instron 5565 universal testing machine. RESULTS： l.ens-induced （1.1） eyes elongated more rapidly compared with fellow eyes with AXI. values of 15.56±0.14 and 15.21±0.14 mm （P〈0.01）. Fibril diameter was significantly smaller in the I.I eyes compared with control ones in the inner, middle, and outer layers （inner layer, 63.533 vs 76.467 nm; middle layer, 92.647 vs 123.984 nm; outer layer, 86.999 vs 134.257 nm, P〈0.01, respectively）. In comparison with control eyes, macrophage-like cells that engulfed fibroblasts, dilated endoplasmic reticulum, and vacuoles in fibroblasts were observed in the inner and middle stroma in the/U eyes. Ultimate stress and Young＇s modulus were lower in the I.I eyes compared with those in the control eyes. CONCLUSION： Negative lens application alters eye growth, and results in axial elongation with changes in scleral ultrastructural and mechanical properties.

A Multi-Agent Immunology Model for Security Computer

This paper presents a computer immunology model for computer security, whose main components are defined as idea of Multi Agent. It introduces the natural immune system on the principle, discusses the idea and characteristics of Multi Agent. It gives a system model, and describes the structure and function of each agent. Also, the communication method between agents is described.

Effect of dietary supplementation with insect fats on growth performance,digestive efficiency and health of rabbits

Background: The present work aimed at evaluating the effect of the dietary replacement of soybean oil(S) by two types of insect fats extracted from black soldier fly larvae(H, Hermetia il ucens L.) and yel ow mealworm larvae(T, Tenebrio molitor L.) on growth performance, nutrient digestibility, blood parameters, intestinal morphology and health of growing rabbits.Methods: At weaning, 200 crossbred rabbits(36 days old) were allotted to five dietary treatments(40 rabbits/group): a control diet(C) containing 1.5% of soybean oil and four experimental diets where soybean oil was partially(50%) or totally(100%) substituted by H(H50 and H100) or T(T50 and T100) fats. Total tract digestibility was evaluated on 12 rabbits per treatment. The growth trial lasted 41 d and, at slaughtering(78 days old), blood samples were collected from 15 rabbits per treatment, morphometric analyses were performed on duodenum, jejunum and ileum mucosa,and samples of liver, spleen and kidney were submitted to histological evaluation.Results: No difference was observed between the control and the experimental groups fed insect fats in terms of performance, morbidity, mortality and blood variables. The addition of H and T fats did not influence apparent digestibility coefficients of dry matter, protein, ether extract, fibre fractions and gross energy. Gut morphometric indices and organ histopathology were not affected by dietary inclusion of H and T fats.Conclusions: H and T fats are suitable sources of lipid in rabbit diets to replace soybean oil without any detrimental effect on growth performance, apparent digestibility, gut mucosa traits and health.

Effects of exogenous enzymes, Lactobacillus acidophilus or their combination on feed performance response and carcass characteristics of rabbits fed sugarcane bagasse

The aim of this study was to evaluate the effect of Lactobacillus acidophilus（LAC）, exogenous enzymes of ZAD（exogenous enzyme preparation） or their combination on feed conversion, and dressing of rabbits fed different treatments of sugarcane bagasse（SCB）. Five rations were allotted randomly to five groups of New-Zealand White（NZW） rabbits（n=10） with initial live body weight of（838±42.4） g and 5 weeks of age. Rabbits were fed on diets with different sources of fiber as follows,（i） a control diet composed of 100% berseem hay and 0% SCB,（ii） 50% berseem hay and 50% untreated SCB（USCB）,（iii） 50% berseem hay and 50% SCB treated with L. acidophilus（LAC）,（iv） 50% berseem hay and 50% SCB treated with ZAD（ZAD）, and（v） 50% berseem hay and 50% SCB treated with a combination of LAC＋ZAD（LZ）. Treatments of SCB with L. acidophilus, ZAD and LAC＋ZAD had the highest feed conversion ratio than both USCB and control. The dressing percentage of rabbits that fed the LAC and LZ diets was higher（P〈0.05） compared with that in the other groups. Performance index（PI） for LAC group was improved（P〈0.05） compared to that for the other groups; however, PI for USCB group was the lowest（P〈0.05）. It could be concluded that treating SCB with L. acidophilus, exogenous enzymes of ZAD or their combination improved feed conversion and performance with more positive effects with L. acidophilus than the other treatments.

Effects of Electric Stimulations Applied during Absolute Refractory Period on Cardiac Function of Rabbits with Heart Failure

The effects of electric currents applied during absolute refractory period （ARP） on the cardiac function of rabbits with heart failure due to myocardial infarction （MI）, and the safety of this method were investigated. Thirty rabbits were randomly assigned equally to 3 groups： sham-operated group, LV-anterior wall cardiac contractility modulation （LV-CCM） group, and septum-CCM （S-CCM） group. A thoracotomy was performed on all the rabbits. Electric pulses were delivered during the ARP on the anterior wall of left ventricle in CCM group and in the septum in S-CCM group, respectively. The left ventricular systolic pressure （LVSP） and maximum positive left ventricular pressure change （＋dp/dtmax）, heart rates, ventricular tachycardia, ventricular fibrillation were observed. It was found that, as compared with the baseline, LVSP, and ＋dp/dtmax were significantly increased, on average, by 15.2% and 19.5% in LV-CCM group （P〈0,05）, and by 8.5% and 10.8% in S-CCM group （P〈0.05）. LVEDP was significantly decreased and -dp/dtmx increased both in LV-CCM group and S-CCM group （P〈0.05）. CCM had no effect on heart rate and induced no arrhythmia in short time. It is concluded that electric currents delivered during the ARP could significantly enhance the contractility of myocardium safely, suggesting that CCM stimulation is a novel potent method for contractility modulation.

Application of sustained delivery microsphere of cyclosporine A for preventing posterior capsular opacification in rabbits

AIM:To explore the inhibitory effect of a sustained cyclosporin A (CsA) delivery microsphere (CsA-MS) on posterior capsular opacification (PCO) in rabbit eyes after cataract extraction. ·METHODS:Twenty New Zealand white rabbits accepted cataract extraction plus intraocular lens implantation and their left eyes were intraoperatively injected CsA-MS prepared using polymer polylactioglycolic acid (PLGA) as a carrier and their right eyes were injected with empty MS. The changes in cornea, anterior chamber reaction, intraocular pressure, PCO and CsA concentration in aqueous humor were examined postoperatively and all the eyes were enucleated 3 months after surgery for histopathological and morphological examination with light microscopy and electron microscopy. · RESULTS:Conjunctival hyperemia, corneal edema, intraocular pressure and anterior chamber response of experimental and control eyes were similar, while PCO in CsA MS injected eyes was greatly improved compared with that in control eyes. Posterior capsules in CsA-MS injected eyes were smooth and lens epithelial cells (LEC) did not proliferate significantly (P 】0.05), while LEC in posterior capsule of control eyes had different degrees of proliferation and cortical regeneration. LEC in CsA-MS injected eyes were not functionally active and underwent apoptosis, whereas LEC in control eyes were functionally active (F-test, P =0.025). In addition, the cornealultrastructure showed no differences between CsA-MS and MS injected eyes. CONCLUSION:CsA-MS has high bioavailability in rabbit eyes and could inhibit postoperative PCO occurrence and development during the study period, suggesting that CsA-MS may be a promising, effective and safe administration route to prevent PCO in clinic.