主动脉瓣关闭不全法建立新西兰兔心衰模型

目的 用主动脉瓣关闭不全法致新西兰兔心衰模型。方法 运用导管术造成新西兰兔主动脉瓣膜关闭不全, 制作超容量负荷型心衰模型。观察动物的毛色、精神状态、活动情况、饲料消耗指数、体重增加指数、呼吸频率等指标对该模型进行评价;检测血清SOD活力和MDA含量, 判断模型组动物机体抗氧化能力;利用酶联免疫法检测血清中cAMP、cGMP的变化情况;利用基因芯片技术分析该模型基因表达差异。结果 模型动物SBP、DBP和LVSP著性下降, LV+dp/dt和LV±dp/dt明显下降, LVDP显著上升。模型组与正常组比较, 毛发枯槁, 活动减少, 进食减少, 反应迟钝, 精神萎靡, 抓起时反抗减轻。模型组呼吸频率加快;模型组血清SOD活性低于正常组, MDA含量高于正常组;模型组血清cAMP明显低于正常组, cGMP明显高于正常组;利用基因芯片共检测出665个差异基因, 其中与心功能较密切相关的基因主要与离子通道、肌收缩、信号转导等功能有关。结论 采用主动脉瓣关闭不全法建立兔心衰模型方法可靠。主动脉关闭不全, 使心脏前负荷增加, 造成左心室舒张末期容积增加, 导致左心室扩大肥厚及心力衰竭。心肌组织基因芯片检测结果显示, 该模型基因表达出现了一定的变化。     

乌司他丁对脑出血模型兔血清基质金属蛋白酶-9、半胱天冬氨酸蛋白酶-3的影响

目的观察乌司他丁对脑出血模型兔血清基质金属蛋白酶-9(MMP-9)、半胱天冬氨酸蛋白酶-3(Caspase-3)的影响,探讨乌司他丁的脑保护作用。方法将造模成功的20只新西兰兔随机分为脑出血模型组(模型组)和乌司他丁治疗组(治疗组),每组10只。分别给予生理盐水和乌司他丁注射液,静脉推注,共7天。应用ELISA法测定各组兔脑出血后第1、3、5、7天动脉血基质金属蛋白酶-9(MMP-9)、半胱天冬氨酸蛋白酶-3(Caspase-3)含量。结果与模型组比较,治疗第1天治疗组MMP-9[(951.72±216.35)ng/L]、Caspase-3[(58.11±5.07)μmol/mL]差异无统计学意义(P0.05);治疗第3、5、7天,治疗组MMP-9[分别为(887.02±205.77)ng/L、(892.79±123.94)ng/L、(858.90±97.37)ng/L]及Caspase-3[分别为(58.00±4.99)μmol/mL、(49.05±9.30)μmol/mL、(48.22±10.28)μmol/mL]含量均明显下降,差异有统计学意义(P均0.05)。结论乌司他丁可下调脑出血模型兔血清MMP-9及Caspase-3含量,对脑出血具有一定的脑保护作用。     

A rabbit monoclonal antibody-based sensitive competitive indirect enzyme-linked immunoassay for rapid detection of chloramphenicol residue

A sensitive competitive indirect enzyme-linked immunoassay (ciELISA) based on a rabbit monoclonal antibody (RabMAb) against chloramphenicol (CAP) has been developed and validated in this study. After optimisation of several key physicochemical factors, such as Tween-20 percentage, pH value and ionic strength, the immunoassay showed excellent performance within the linear range of 0.18–6.37 ng mL^?1, with the 50% inhibition concentration (IC₅₀) of 1.06 ng mL^?1 and the limit of detection (LOD) of 0.1 ng mL^?1. In addition, the cross-reactivities of RabMAb towards chloramphenicol succinate, florfenicol and thiamphenicol were 2.09, 12.45 and 18.10%, respectively. Finally, the developed method was applied in spiked swine urine, milk and honey samples, with recoveries ranging from 71.03 to 109.62%. The result demonstrated that the developed immunoassay is a valuable method for screening and quantitation of CAP residues in real samples.     

Morphological pattern of intrinsic nerve plexus distributed on the rabbit heart and interatrial septum

Although the rabbit is routinely used as the animal model of choice to investigate cardiac electrophysiology, the neuroanatomy of the rabbit heart is not well documented. The aim of this study was to examine the topography of the intrinsic nerve plexus located on the rabbit heart surface and interatrial septum stained histochemically for acetylcholinesterase using pressure‐distended whole hearts and whole‐mount preparations from 33 Californian rabbits. Mediastinal cardiac nerves entered the venous part of the heart along the root of the right cranial vein (superior caval vein) and at the bifurcation of the pulmonary trunk. The accessing nerves of the venous part of the heart passed into the nerve plexus of heart hilum at the heart base. Nerves approaching the heart extended epicardially and innervated the atria, interatrial septum and ventricles by five nerve subplexuses, i.e. left and middle dorsal, dorsal right atrial, ventral right and left atrial subplexuses. Numerous nerves accessed the arterial part of the arterial part of the heart hilum between the aorta and pulmonary trunk, and distributed onto ventricles by the left and right coronary subplexuses. Clusters of intrinsic cardiac neurons were concentrated at the heart base at the roots of pulmonary veins with some positioned on the infundibulum. The mean number of intrinsic neurons in the rabbit heart is not significantly affected by aging: 2200 ± 262 (range 1517–2788; aged) vs. 2118 ± 108 (range 1513–2822; juvenile). In conclusion, despite anatomic differences in the distribution of intrinsic cardiac neurons and the presence of well‐developed nerve plexus within the heart hilum, the topography of all seven subplexuses of the intrinsic nerve plexus in rabbit heart corresponds rather well to other mammalian species, including humans.     

脑室亚低温对急性脑梗塞脑组织兔细胞凋亡和Caspase-3表达的影响

目的检测低温组和常温组家兔大脑中动脉脑梗塞周边缺血区脑组织细胞凋亡和Caspase-3表达,探讨脑室内低温对家兔大脑中动脉梗塞模型脑组织细胞凋亡影响。方法选用4-6个月龄雄性家兔20只,随机分为常温组(10只)和低温组(10只)。应用线栓法建立大脑中动脉闭塞(MCAO)模型,进行脑室内穿刺低温液体灌注亚低温干预,术后动物行为观察,SP和Western blot法检测各组脑组织Caspase-3的表达,TUNEL方法检测细胞凋亡。结果术后24h神经病学体征评分低温组明显优于常温组(P0.05),低温组的TUNEL染色凋亡细胞数和Caspase-3染色阳性细胞数明显低于常温组(P0.05),Western blot表明低温组脑组织中Caspase-3的表达水平明显低于常温组(P0.05)。结论脑室内穿刺低温干预对急性脑梗塞动物模型有脑保护作用。     

TNF-α抗体对Sp1和NF-κ B p65在兔粘连腹膜表达的影响

目的探讨TNF-α抗体对实验兔腹膜损伤粘连修复演变过程中核转录因子Sp1和NF-κB p65活化的影响。方法实验兔随机分3组:正常对照组(不做任何处理)、模型组(腹膜腔内注入生理盐水)、TNF-α抗体组(造模后后腹膜腔内注入TNF-α抗体),每组30只,共90只。建立实验兔腹膜回盲部手术动物模型,ELISA检测腹水Sp1、NF-κB p65的表达,Masson染色检测Sp1在腹膜的表达、免疫组化SP法检测NF-κB p65在腹膜的表达,监测腹膜粘连分级变化。结果 TNF-α抗体导致Sp1和NF-κB p65在损伤腹膜和腹水中的表达水平显著减低(0.01),并有效减轻腹膜粘连形成。结论 TNF-α抗体有效减轻腹膜粘连形成可能与其下调Sp1和NF-κB p65表达相关。     

眼络通方对兔视网膜静脉阻塞模型促血管新生因子PDGF、VEGF表达的影响

[目的]探讨眼络通方对视网膜静脉阻塞(retinal vein occlusion,RVO)新西兰兔视网膜血管新生的影响。[方法]将48只健康新西兰兔随机分为空白对照组12只和模型组36只,模型组以氩激光光凝,建立RVO模型,并随机分为模型对照组、天保宁组、眼络通组,每组各12只。空白对照组及模型对照组予0.9%氯化钠溶液灌胃5mL/(kg·d);天保宁组灌胃给药剂量为0.02g/(kg·d);眼络通组灌胃给药剂量6.9g/(kg·d),连续给药4周。分别于灌胃治疗第1、2、4周后每组各处死4只新西兰兔,以免疫组化与Western blot法检测视网膜组织血小板源性生长因子(platelet-derived growth factor,PDGF)、血管内皮细胞生长因子(vascular endothelial growth factor,VEGF)的蛋白表达,实时荧光定量PCR (real-time quantitative polymerase chain reaction,RT-PCR)检测视网膜组织PDGF、VEGF的mRNA表达,并对相关数据进行统计学分析。[结果]与空白对照组比较,模型对照组1、2、4周各时相视网膜组织中PDGF、VEGF蛋白与mRNA表达量均显著升高(P0.05);与模型对照组比较,眼络通组1、2、4周各时相视网膜组织中PDGF、VEGF蛋白与mRNA的表达量均显著降低(P0.05),但仍显著高于空白对照组(P0.05);而天保宁组各时相视网膜组织中PDGF、VEGF蛋白与m RNA的表达量差异无统计学意义(P0.05)。[结论]眼络通方通过抑制视网膜组织VEGF、PDGF的表达,减少促血管新生因子释放,从而抑制视网膜血管新生,发挥保护视网膜、治疗RVO的作用。     

复方苯佐卡因凝胶的局部毒性研究

目的评价复方苯佐卡因凝胶的局部刺激性和致敏性。方法依照国家食品药品监督管理局《化学药物刺激性、过敏性和溶血性研究技术指导原则》（以下简称指导原则）,采用大鼠口腔黏膜刺激性实验法、兔眼刺激性实验法以及豚鼠皮肤致敏实验法。结果复方苯佐卡因凝胶给大鼠口腔正常黏膜连续涂药3次,相当于3g·kg-1,均无刺激和毒性反应;一次性按每只0．1g给兔眼结膜涂药,亦未出现刺激性反应;给每只豚鼠皮肤0．2g致敏接触和激发接触,均无过敏反应发生。结论复方苯佐卡因凝胶对口腔黏膜无刺激性,对皮肤也没有致敏性。     

牙龈卟啉单胞菌对兔血管平滑肌细胞分泌IL-1β、IL-6的影响

目的:观察牙龈卟啉单胞菌(Porphyromonas gingivalis,Pg)上清液对体外培养的兔血管平滑肌细胞分泌IL-1β、IL-6的影响。方法:组织块法培养兔腹主动脉血管平滑肌细胞,并对其细胞来源进行鉴定。用4.3×106 CFU/mL的Pg上清液刺激细胞12、24、48 h后,通过ELISA检测IL-1β、IL-6的水平;同时用RT-PCR检测其mRNA表达的情况。结果:Pg上清液刺激24 h和48 h时能促进血管平滑肌细胞分泌IL-6,分别与同一时间点的对照组相比差异均有统计学意义(P<0.05),而且24 h时,IL-6表达最强,而IL-1β的表达最低,明显低于相同时间的对照组和其他时间点的实验组(P<0.05)。RT-PCR检测显示,4.3×106 CFU/mL的Pg上清刺激血管平滑细胞12、24、48 h后细胞内均有IL-1β、IL-6的基因表达,在24 h时,血管平滑肌细胞的IL-1β基因表达减少,而IL-6基因表达增加。结论:Pg上清液可促进细胞合成和分泌IL-6,在动脉粥样硬化的发生发展过程中可能发挥一定作用。