立体定向边缘叶脑白质切开术对大鼠强迫检查行为学改变的影响

目的探讨立体定向边缘叶脑白质切开术对Quinpirole(QNP)引起大鼠强迫性检查行为的影响。方法给大鼠颈部皮下注射QNP建立强迫检查行为动物模型,采用立体定向进行大鼠边缘叶脑白质切开术,在开放场地观察大鼠返“家”频率、平均返回时间、运动总距离、参观地点、参观序列及预期比率,评价大鼠的行为学改变,并与假手术组和氯丙咪嗪处理组对比,观察手术对大鼠强迫检查行为的影响。结果术后2周大鼠返“家”频率及运动总距离与假手术组相比明显减少,平均返回时间延长,参观序列及实际/预期比率出现明显差异,而参观地点没有明显改变。氯丙咪嗪处理可以减弱大鼠过度返“家”次数,延长大鼠平均返回时间,但不影响其他强迫检查行为。结论边缘叶脑白质切开术和氯丙咪嗪处理均能明显改善QNP诱发的大鼠强迫检查行为。     

强迫检查行为大鼠动物模型的建立与评价

目的探讨强迫检查行为大鼠动物模型的制作方法及理论依据。方法应用多巴胺激动剂Quinpirole(QNP)处理大鼠, 在开放场地观察大鼠返“家”频率、平均返回时间、运动总距离、参观地点、参观序列及预期比率,评价大鼠的行为学改变,并与生理盐水和氯丙咪嗪处理组对比验证大鼠强迫检查行为。结果QNP组大鼠接受10次QNP注射后,在开放场地与盐水对照组相比返“家”频率及运动总距离明显增加,参观地点、参观序列及平均返回时间明显减少,实际参观家的频率是预期次数的4.68±1.53倍,明显高于盐水对照组。氯丙咪嗪能部分缓解QNP大鼠的强迫检查行为,但不能终止强迫检查行为。绪论大鼠强迫检查行为与OCD部分临床表现有表面相似性,QNP处理大鼠可作为OCD的一种动物模型用于临床研究。     

杏仁核毁损对甲基苯丙胺精神分裂症大鼠边缘区多巴胺D2受体的影响

目的探讨立体定向杏仁核毁损对甲基苯丙胺(methamphetamine,MAP)精神分裂症大鼠脑内边缘区多巴胺D2受体表达的影响.方法40只SD大鼠随机分为对照组、模型组、假手术组和手术组,每组各10只;采用经腹腔注射MAP制备精神分裂症MAP模型,立体定向-射频毁损杏仁核,原位杂交法观察边缘区多巴胺D2受体的表达.结果与对照组比较,模型组及假手术组大鼠边缘区多巴胺D2受体表达有非常显著性差异(P＜0.01);手术组大鼠边缘区多巴胺DA受体阳性细胞数目与对照组比较差异无显著性(P＜0.01).结论杏仁核毁损可以抑制使用MAP而诱发的边缘区D2表达的亢进.     

伏隔核毁损对MAP模型大鼠行为及脑内DA受体影响的研究

目的探讨立体定向伏隔核毁损对甲基苯丙胺(MAP)模型大鼠行为学及不同脑区多巴胺D2受体表达的影响。方法80只SpraqueDawley(SD)大鼠随即分为对照组、模型组、假手术组和手术组,每组各20只;采用经腹腔注射MAP制备精神分裂症模型,立体定向-直流电毁损伏隔核,观察大鼠刻板行为变化,原位杂交法观察额叶、颞叶、边缘区及脑干部位D2受体表达。结果与对照组比较,模型组及假手术组大鼠刻板行为评分及各个脑区D2受体表达均显著增加;而与模型组及假手术组比较,手术组大鼠刻板行为评分及各脑区DA受体阳性细胞数目均显著减少。结论伏隔核毁损可能是通过抑制使用MAP而诱发的脑内D2表达的亢进而改变其行为学的异常。     

氧化应激在慢性缺血性脑白质损伤中的作用

目的 阐明氧化应激是否参与大鼠慢性脑缺血所致的脑白质损伤.方法 健康雄性Wistar大鼠按照完全随机数字表法分为假手术组,持久性双侧颈总动脉结扎3 d组、7 d组、3周组及6周组,每组6只.应用大鼠双侧颈总动脉结扎制备慢性脑缺血模型,检测大鼠脑白质内超氧化物歧化酶(SOD)活性、过氧化氢酶(CAT)活性、谷胱甘肽(GSH)含量以及脂质过氧化产物丙二醛(MDA)和4-羟基壬烯醛(4-HNE)加合物的变化.结果 与假手术组比较,慢性脑缺血大鼠脑白质内MDA含量在手术后3周明显增加,手术后6周进一步增高,差异有统计学意义(P<0.05).手术后3d至6周,慢性脑缺血大鼠脑白质内4-HNE蛋白加合物逐渐增高,与假手术组比较有差异有统计学意K(P<0.05).SOD活性在手术后3周和6周才明显降低,与假手术组比较差异有统计学意义(P<0.05).此外,慢性脑缺血大鼠脑白质内GSH含量在手术后7d即开始降低,而在手术后3周及6周则进一步下降,与假手术组比较差异有统计学意义(P<0.05).结论 慢性脑缺血导致大鼠脑白质氧化性损伤增加,抗氧化防御能力降低:氧化性损伤的增加和抗氧化防御能力的降低与慢性脑缺血所致的脑白质损伤密切相关.     

伏隔核毁损对MAP模型大鼠行为及脑内DA受体的影响

目的 探讨立体定向伏隔核毁损对甲基苯丙胺（MAP）模型大鼠行为学及不同脑区多巴胺D2受体表达的影响。方法 将80只SD大鼠随机分为对照组、模型组、假手术组和手术组，每组各20只。经腹腔注射MAP制备精神分裂症模型，采用立体定向一直流电毁损伏隔核，观察大鼠刻板行为变化；并采用原位杂交法观察额叶、颞叶、边缘区及脑干部位的D2受体表达。结果 与对照组比较，模型组及假手术组大鼠刻板行为评分及各个脑区D2受体表达均显著性增加；与模型组及假手术组比较，手术组大鼠刻板行为评分及各脑区DA受体阳性细胞数目均显著性减少。结论 伏隔核毁损可能通过抑制MAP诱发的脑内D2表达亢进而改变其行为学异常。     

雌激素对脑卒中后抑郁大鼠抑郁行为学及前额叶BDNF表达的影响

目的:探讨雌激素对脑卒中后抑郁(PSD)大鼠的影响及分子机制.方法:应用大脑中动脉栓塞和慢性不可预见温和刺激方法制备大鼠PSD模型.将PSD大鼠分为雌激素组(PSD大鼠皮下注射雌二醇),PSD组(PSD大鼠皮下注射大豆油)和对照组(假手术,皮下注射大豆油).3组的不同干预均持续14 d.观察各组大鼠行为学和前额叶脑源性生长因子(BDNF)的含量改变.结果:雌激素组在雌二醇干预后强迫游泳测试结果表明行为学显著改善:不动时间减少,与PSD组比较(18.4±4.84 vs 52.1±5.38)差异有显著统计学意义(P<0.01),雌激素组挣扎时间增加,与PSD组比较(63.8±12.31 vs 36.3±5.22)差异有统计学意义(P<0.05).前额叶BDNF含量在雌激素组也显著增高:雌激素组与PSD组比较,P<0.05;PSD组与对照组比较,P<0.01.结论:雌激素可能通过BDNF通路改善PSD大鼠的抑郁症状.     

高血压大鼠脑白质病变中髓鞘和轴索改变

目的探究高血压大鼠脑白质病变中轴索微结构的变化。方法 18只雄性Sprague-Dawley大鼠,随机分为假手术组(n=9)与手术组(n=9),手术组先行双肾双夹术制作易卒中型肾血管性高血压大鼠模型,12周后间隔1 d先后夹闭双侧颈总动脉。颈总动脉夹闭术后12周对大鼠进行水迷宫试验评价大鼠是否存在认知功能受损,组织病理学评价小血管病理学改变、脑白质病变、胶质细胞改变及轴索微结构的变化。结果水迷宫实验:手术组的逃避潜伏期较假手术组明显升高,穿越平台次数较假手术组明显降低,差异具有统计学意义(P0.05)。手术组大鼠存在小动脉内膜增厚、管腔狭窄;手术组较假手术组有明显的脑白质病变,且伴有少突胶质细胞减少;手术组病变部位Caspr表达明显减少,病变周围髓鞘正常区域出现郎飞结长度增加、结侧区长度增加及直径增粗。结论脑白质病变过程同时存在轴索和髓鞘的损伤。     

大鼠脑缺血再灌注后Caspase-3、Bcl-2和Bax的表达

目的探讨大鼠脑缺血再灌注后caspase-3、Bcl-2和Bax在脑皮质神经元中的表达。方法将动物随机分为假手术组及缺血组,参照zea longa线栓法建立大鼠左侧大脑中动脉闭塞(middle cerebral artery occlusion,MCAO)局灶性脑缺血再灌注模型,各组大鼠分别在左侧MCAO2h再灌注不同时间点断头取脑,脑皮质神经元中caspase-3、Bcl-2和Bax的表达通过免疫组化法来测定。结果缺血组大鼠脑皮质caspase-3的表达较假手术组显著增强(P<0.01),缺血组大鼠脑皮质Bcl-2的表达较假手术组显著增强(P<0.01),缺血组大鼠脑皮质Bax的表达较假手术组显著增强(P<0.01)。结论短暂性脑缺血再灌注上调脑皮质神经元中caspase-3和Bax的表达促细胞凋亡,上调脑皮质神经元中Bcl-2的表达抗细胞凋亡。     

密闭舱室内亚致死性爆炸伤大鼠额叶皮质及血浆内单胺类神经递质的变化对大鼠旷场行为的影响

目的: 观察密闭舱室内亚致死剂量爆炸伤大鼠额叶皮质及血浆内单胺神经递质的变化对大鼠旷场行为的影响.方法:采用密闭舱室内亚致死剂量爆炸伤的大鼠模型,高效液相色谱电化学法分析大鼠血浆、额叶皮质内5-羟色胺(5-HT),多巴胺(DA),肾上腺素(E).去甲肾上腺素(NE)含量的变化,用旷场行为观察箱观察大鼠旷场行为.结果: 舱内亚致死剂量爆炸伤大鼠额叶皮质内NE,E含量较对照组明显升高(P<0.05),DA含量明显降低(P<0.05),5-HT的含量在爆炸后48 h达高峰,随后出现下降,密闭舱室内亚致死剂量爆炸后大鼠旷场行为较对照组明显减少(P<0.05).结论: 舱内爆炸后大鼠的兴奋性明显下降;大鼠旷场行为与舱内爆炸后额叶皮质E浓度呈负相关(r=-0.987,P<0.05),与5-HT浓度呈正相关(r=0.952,P<0.05),大鼠旷场行为与血浆内E浓度呈正相关(r=0.979,P<0.05),而与5一HT的浓度成负相关(r=-0.958,P<0.05).     

过表达BCL-2对急性脑梗死大鼠神经功能的影响

目的探讨采用慢病毒介导Bcl-2在急性脑梗死大鼠脑组织过表达对神经功能的影响。方法 45只大鼠随机分为假手术组、模型组和治疗组。假手术组和模型组分别于手术前10 d通过颅内动脉给予慢病毒空载体,治疗组给予慢病毒Bcl-2过表达载体。在采用线栓法制作大鼠大脑中动脉脑梗死模型72 h后,分析大鼠脑组织梗死范围、脑细胞凋亡指数以及神经功能的变化。结果慢病毒介导的Bcl-2表达质粒可在大鼠脑组织中表达,治疗组大鼠脑组织中Bcl-2的水平明显高于假手术组和模型组;与假手术组比较,模型组和治疗组脑组织神经细胞凋亡指数和脑组织梗死范围明显增加(P<0.05),而治疗组神经细胞凋亡指数和脑组织梗死范围较模型组明显下降(P<0.05);治疗组大鼠神经功能损伤评分较模型组明显下降(P<0.05)。结论过表达Bcl-2可降低大鼠脑组织神经细胞凋亡水平,对神经具有一定保护作用,为临床急性脑梗死治疗提供了一定的参考依据。     

Features of compulsive checking behavior mediated by nucleus accumbens and orbital frontal cortex

The quinpirole sensitization model of obsessive‐compulsive disorder was used to investigate the functional role that brain regions implicated in a neuroanatomical circuit of obsessive‐compulsive disorder may play in compulsive checking behavior. Following repeated injections of saline or quinpirole (0.5 mg/kg, twice per week, ×8 injections) to induce compulsive checking, rats received N‐methyl‐d ‐aspartate lesions of the nucleus accumbens core (NAc), orbital frontal cortex (OFC) and basolateral amygdala, or sham lesions. When retested at 17 days post‐surgery, the results showed effects of NAc and OFC but not basolateral amygdala lesion. NAc lesions affected measures indicative of the amount of checking behavior, whereas OFC lesions affected indices of staying away from checking. The pattern of results suggested that the functional roles of the NAc and OFC in checking behavior are to control the vigor of motor performance and focus on goal‐directed activity, respectively. Furthermore, similarities in behavior between quinpirole sham rats and saline NAc lesion rats suggested that quinpirole may drive the vigor of checking by inhibition of NAc neurons, and that the NAc may be a site for the negative feedback control of checking.     

Effect of nicotine on quinpirole-induced checking behavior in rats: implications for obsessive-compulsive disorder.

BACKGROUND: Rats treated chronically in a large, open field with the dopamine D2/D3 receptor agonist quinpirole (QNP) develop compulsive checking behavior as defined by a set of behavioral criteria. This paradigm has been suggested as an animal model of obsessive-compulsive disorder (OCD). Because nicotine blocks various behaviors induced by ontogenetic QNP administration, we asked whether nicotine could attenuate QNP-induced compulsive checking. METHODS: Adult male Long-Evans rats (n = 14/group) were treated twice weekly with saline (control), or with QNP (0.5 mg/kg) for 14-16 injections. On the last two injections, rats were pretreated in random order with an acute dose of nicotine (0.3 mg/kg base) or saline 10 min before administration of QNP or saline; and the effects on checking behavior was examined. The effects of chronic QNP treatment on nicotinic receptors in discrete brain regions were also determined. RESULTS: Chronic QNP resulted in compulsive checking and increases in cerebellar alpha4beta2 and alpha7 nicotinic receptor densities. Nicotine pretreatment significantly reduced one of the three measures of compulsive checking behavior. CONCLUSIONS: Nicotine attenuates some symptoms of compulsive checking in a rat model of OCD; however, the mechanisms of this effect and therapeutic efficacy of nicotinic agonists in OCD require further study.     

High-frequency stimulation of the nucleus accumbens core and shell reduces quinpirole-induced compulsive checking in rats

Electrical deep brain stimulation (DBS) is currently studied in the treatment of therapy-refractory obsessive compulsive disorders (OCDs). The variety of targeted brain areas and the inconsistency in demonstrating anti-compulsive effects, however, highlight the need for better mapping of brain regions in which stimulation may produce beneficial effects in OCD. Such a goal may be advanced by the assessment of DBS in appropriate animal models of OCD. Currently available data on DBS of the nucleus accumbens (NAc) on OCD-like behavior in rat models of OCD are contradictory and partly in contrast to clinical data and theoretical hypotheses about how the NAc might be pathophysiologically involved in the manifestation of OCD. Consequently, the present study investigates the effects of DBS of the NAc core and shell in a quinpirole rat model of OCD. The study demonstrates that electrical modulation of NAc core and shell activity via DBS reduces quinpirole-induced compulsive checking behavior in rats. We therefore conclude that both, the NAc core and shell constitute potential target structures in the treatment of OCD.     

骨髓单个核细胞对脑梗死大鼠炎症反应的影响

目的探讨骨髓单个核细胞(BMMNCs)是否通过抑制脑梗死大鼠脑内的炎症反应来发挥神经保护作用。方法选择健康雄性SD大鼠,体质量为250~300 g,线栓法制备永久性大脑中动脉闭塞模型(p MCAO),造模成功后,随机分为4组:假手术组(Sham组)、模型组(Model组)、溶剂组(Vehicle组)、骨髓单个核细胞组(BMMNCs组)。其中BMMNCs组于造模24 h后经尾静脉注射含1×107BMMNCs的PBS细胞悬液200μl;溶剂组注射等量的PBS溶液,分别于24 h、72 h、7 d采用Zea-Longa法进行神经功能评分;干湿重法检测脑组织含水量;TTC法测定脑梗死体积;免疫组化、Western blot技术检测炎性介质环氧化酶-2(COX-2)、白介素-1β(IL-1β)的表达情况。结果 (1)各时间点模型组Zea-Longa评分、脑组织含水量和脑梗死体积均明显高于假手术组(P0.05),BMMNCs组低于模型组,高于假手术组(P0.05),模型组与溶剂组相比无差异(P0.05);(2)各时间点模型组COX-2和IL-1β水平明显均高于假手术组(P0.05),BMMNCs组低于模型组,高于假手术组(P0.05),模型组与溶剂组相比无差异(P0.05)。结论骨髓单个核细胞移植可通过抑制梗死后脑内免疫炎症反应,显著改善脑梗死大鼠的神经功能,这一治疗作用可能与下调COX-2、IL-1β的表达有关。     

法舒地尔对脑出血大鼠神经功能的影响

目的 探讨法舒地尔对脑出血大鼠神经功能的保护作用及机制。方法 将60只SD大鼠随机分为:假手术组、模型组、低剂量法舒地尔组（低剂量组）和高剂量法舒地尔组（高剂量组）；每组15只。通过注射自体脑内动脉血制作脑出血模型，假手术组只暴露硬脑膜，不注射动脉血。低剂量组腹腔注射1 mg/（kg·d）法舒地尔，高剂剂量组腹腔注射10 mg/（kg·d）法舒地尔。模型组和假手术组腹腔注射等体积生理盐水。药物干预4周后，使用Y-迷宫法评价大鼠学习记忆功能，记录大鼠错误反应次数；使用Longa法评价大鼠神经功能。干湿重法测定脑组织含水量，使用硝酸溶解法测定Na+、K+含量，TUNEL染色分析神经细胞凋亡率，免疫印迹法分析凋亡相关蛋白表达（Bax、Bcl-2和Caspase-3）。结果 相比假手术组，模型组大鼠逃离错误次数、Longa神经功能评分、脑组织含水量、脑组织Na+离子水平、神经细胞凋亡率、Caspase-3和Bax蛋白表达水平显著升高（P<0.01），脑组织K+离子水平、Bcl-2蛋白表达水平显著降低（P<0.01）。相比模型组，法舒地尔模型逆转大鼠脑出血后上述变化（P<0.01），而且高剂量法舒地尔明显优于低剂量法舒地尔（P<0.01）。结论 大鼠脑出血后，法舒地尔可以调节神经细胞Na+、K+离子平衡并减少脑组织水肿、抑制神经细胞凋亡，保护大鼠神经功能     

The role of the subthalamic nucleus in 'compulsive' behavior in rats

Different lines of evidence point to dysfunction of basal ganglia-thalamocortical circuits in obsessive-compulsive disorder (OCD). It has been hypothesized that the circuits' dysfunction in OCD may be characterized by a relative under-activity of the indirect compared with the direct pathway within these circuits. The present study tested whether lesions of the subthalamic nucleus (STN), a major node of the indirect pathway, would affect compulsive behavior, using the signal attenuation rat model of OCD. In this model, compulsive lever-pressing is induced by the attenuation of an external signal of reward delivery; an attenuation that is hypothesized to simulate the deficient response feedback suggested to underlie obsessions and compulsions in patients with OCD. Rats sustaining lesions to the STN showed a selective increase in compulsive lever-pressing compared with sham-operated rats. A post mortem biochemical analysis revealed a decrease in serotonin content in the prelimbic and infralimbic cortices, caudate-putamen (but not nucleus accumbens), globus pallidus and substantia nigra-ventral tegmental area, as well as a decrease in dopamine content in the caudate-putamen in STN-lesioned compared with sham rats. A comparison to recent findings that lesions to the orbitofrontal cortex, which also result in a selective increase in compulsive lever-pressing, lead to a decrease in serotonin and dopamine content in the caudate-putamen suggests that there may be a final common pathway by which different brain pathologies may lead to a pro-compulsive state.     

Changes in adult brain and behavior caused by neonatal limbic damage: implications for the etiology of schizophrenia

We tested the hypothesis that limbic damage in early development can cause aberrant maturation of brain structures known to be abnormal in adult schizophrenics: the hippocampus, prefrontal cortex, ventricles, and forebrain dopamine systems. We measured brain morphology, locomotor response to apomorphine, and cognitive processes in adult rats which received electrolytic damage to amygdala or hippocampus 48 h after birth. The behavioral measurements involved tasks which depend upon the integrity of the hippocampus or prefrontal cortex, and a task sensitive to forebrain dopamine system activation. The tasks included place navigation, egocentric spatial ability, and apomorphine-induced locomotion. The rats with lesions showed poor performance on the place navigation and egocentric spatial tasks and more apomorphine-induced locomotion after puberty than the sham lesion group. Regardless of lesion location, the adult rats showed smaller amygdalae and hippocampi, and larger lateral ventricles. Analyzing the lesion and sham rats together, adult amygdala volume was found to be positively correlated with cerebral cortex, prefrontal cortex, and hippocampal volumes and place navigation performance, and was negatively correlated with lateral ventricle volume. This study contributes to our understanding of the pathogenesis of schizophrenia by showing that early damage to limbic structures produced behavioral, morphological, and neuropharmacological abnormalities related to pathology in adult schizophrenics.     

PI3K/AKT信号通路介导脂联素对脑缺血再灌注大鼠的保护作用

目的 探讨磷脂酰肌醇3激酶/蛋白激酶B（phosphatidylinositol-3-kinase/protein kinase B,PI3K/PKB）信号通路介导脂联素对脑缺血再灌注大鼠的保护作用。 方法 随机将SD大鼠分为假手术组、模型组、脂联素治疗组和PI3K/PKB抑制剂LY294002组（抑制剂组）,每组15只。通过线栓法构建大脑中动脉缺血模型,缺血1.5?h后再灌注。脂联素治疗组在再灌注2?h后,给予大鼠尾静脉注射脂联素（180?μg/100?g）;抑制剂组在再灌注2?h后给予大鼠尾静脉注射脂联素（180?μg/100?g）+LY294004（0.03?mg/100?g）;假手术组和模型组尾静脉注射相应体积的0.9%生理盐水（0.09?mL/100?g）。各组缺血再灌注24?h后,检测各组大鼠脑梗死面积和脑含水量;采用Longa 5分法进行神经功能缺损评分;蛋白质印迹法（Western blotting）检测大鼠脑组织PI3K、PKB、磷酸化的蛋白激酶B（phosphorylated PKB,p-PKB）和脂联素蛋白表达水平;酶联免疫吸附（enzyme linked immunosorbent assay,ELISA）法检测大鼠血清丙二醛（malondialdehyde,MDA）和超氧化物歧化酶（superoxide dismutase,SOD）水平。 结果 与假手术组相比,模型组大鼠的脑梗死面积、脑含水量、神经功能缺损评分和MDA水平均升高（均P<0.001）,SOD、脂联素、PI3K和p-PKB的表达水平均降低（均P<0.001）。与模型组比较,脂联素治疗组大鼠脑梗死面积、脑含水量、神经功能缺损评分和MDA水平均降低（均P<0.001）,SOD、脂联素、PI3K和p-PKB表达水平均升高（均P<0.001）;与脂联素治疗组比较,抑制剂组大鼠脑梗死面积、脑含水量、神经功能缺损评分和MDA水平均升高（均P<0.001）,SOD、脂联素、PI3K和p-PKB表达水平均降低（均P<0.001）。 结论 脂联素对脑缺血再灌注有明显保护作用,该保护机制可能与激活PI3K/PKB信号通路抑制氧化应激相关。