大鼠局灶性脑缺血后的细胞凋亡现象

目的 :研究大鼠局灶性脑缺血再灌注后的细胞凋亡现象及其时间和解剖分布。方法 :雄性SD大鼠 3 0只 ,用改良Longa法制左右侧大脑中动脉梗死模型 ,根据缺血时间不同进行随机分组 ;用电子显微镜和TUNEL染色检测细胞凋亡。结果 :电镜和光镜下显示 ,脑缺血后有DNA断裂和细胞凋亡现象 ,TUNEL染色示随缺血时间延长 ,凋亡细胞数目逐渐增加 ,缺血 1h时为每张切片 (83± 2 1)个 ,2h时为 (2 3 3± 3 6)个 ,4h时为 (3 73± 3 0 )个 (P <0 0 1) ;凋亡细胞主要分布在梗死灶边缘区的内侧。结论 :脑组织缺血后存在着细胞凋亡现象 ,凋亡在梗死灶的发展过程中起一定作用。     

构建大脑中动脉阻塞脑缺血模型大鼠的类型分析

背景：线栓法造成短暂性大脑中动脉阻塞是研究大鼠局灶性脑缺血普遍使用的模型制作方法。但制作大鼠脑缺血模型的类型存在一定差异,可能导致实验结果的偏差。 目的：分析大脑中动脉阻塞线栓法制作大鼠脑缺血模型的类型及其影响因素。 方法：雄性SD大鼠166只,参照Longa线栓法造模,术后24 h行MRI扫描,根据扫描结果将大鼠分成皮质梗死组、皮质下梗死组及无梗死组,分析造模时线栓插入的深度。 结果与结论：皮质梗死组、皮质下梗死组和无梗死组大鼠的线栓插入深度分别为(19.9±0.9),(19.0±1.1)和(17.7±1.3) mm,皮质梗死组大鼠的线栓插入最深,而无梗死组的线栓插入最浅(P < 0.01)。提示插入深度不同导致的大鼠脑梗死的类型也不同,线栓插入越深,皮质梗死的概率可能越大。     

抑郁症患者红细胞儿茶酚氧位甲基转移酶活性的研究

目的探讨抑郁症患者红细胞儿茶酚氧位甲基转移酶(COMT)活性及其与抑郁症发病机制的可能联系。方法采用高效液相色谱法测定110例抑郁症患者(其中单相42例,双相68例;患者组)和120名健康人(对照组)红细胞COMT的活性浓度,对测定结果进行对照比较。结果患者组男女之间、对照组男女之间,单、双相抑郁两组间的红细胞COMT活性浓度的差异均无统计学意义(P>0.05)。患者组的红细胞COMT活性频率分布在2～23μmol·LRBC-1·h-1,其中在11μmol·LRBC-1·h-1附近分布最高;对照组分布在7～28μmol·LRBC-1·h-1,其中在16μmol·LRBC-1·h-1附近分布最高。患者组的红细胞COMT平均活性浓度为(11.0±3.7)μmol·LRBC-1·h-1,其中男性患者COMT活性浓度为(11.2±3.5)μmol·LRBC-1·h-1,女性患者为(10.6±4.0)μmol·LRBC-1·h-1。对照组的红细胞COMT平均活性浓度为(16.1±4.3)μmol·LRBC-1·h-1,其中男性为(16.5±4.6)μmol·LRBC-1·h-1,女性为(15.4±3.9)μmol·LRBC-1·h-1,患者组与对照组以及两组同性别之间的红细胞COMT活性浓度的差异均有统计学意义(均P<0.01)。结论抑郁症患者的红细胞COMT活性浓度低于正常,抑郁症的发病机制可能与血浆红细胞中COMT活性浓度降低有关。     

神经生长因子对大鼠脑缺血再灌注损伤的保护作用及其对Bax表达的影响

目的探讨神经生长因子(NGF)对脑缺血再灌注损伤的保护作用及其对Bax表达的影响。方法采用栓线法制备大鼠局灶脑缺血再灌注模型,大鼠尾静脉注射NGF。应用免疫组化方法检测脑部神经细胞Bax表达,观察大鼠脑部病理改变。结果缺血再灌注组大鼠缺血侧半球皮质及纹状体Bax阳性细胞数为115.25±15.07,NGF组Bax阳性细胞数为70.00±12.77,两组比较差异有极显著性(P<0.01);光镜及电镜观察发现NGF组梗死区病理变化明显轻于缺血再灌注组。结论NGF对脑缺血再灌注损伤具有明确的保护作用,可减轻脑组织的损伤程度,并可减少缺血脑神经细胞Bax表达。     

大鼠局灶性脑缺血模型缺血半暗带的定位研究

目的通过用组织病理学方法结合局部脑血流量(rCBF)测定,对大鼠局灶性脑缺血动物模型缺血半暗带的解剖定位进行初步探讨.方法用线栓法制成大鼠大脑中动脉(MCA)闭塞及再通模型、采用TTC染色法观察分组动物在MCA闭塞的不同时间再灌流48h后脑梗死灶的分布,并用氢清除法测定缺血区rCBF的变化.结果大鼠MCA闭塞1～2h,梗死灶主要位于缺血侧的外侧尾壳核和额顶叶皮质下部;MCA闭塞3h、梗死灶向周围扩大;MCA闭塞4h、梗死灶进一步扩展至大部分新皮质区,但与MCA闭塞6h时无明显区别.MCA闭塞后缺血侧的内侧尾壳核和额顶叶皮质上部rCBF下降至对照组的27%～45%.结论大鼠MCA闭塞后在2～3h的时间窗以内恢复血流,可使位于缺血边缘区的内侧尾壳核和额顶叶皮质上部脑组织被挽救,该区域可能相当于缺血半暗带的等值区.     

白细胞介素8单克隆抗体对大鼠脑缺血再灌注损伤的保护作用

脑缺血再灌注损伤与炎症反应关系密切,白细胞介素8(IL8)作为一种中性粒细胞趋化因子,在脑缺血后炎症损伤中有重要作用[1]。我们设想IL8单克隆抗体(简称IL8单抗)可能对脑缺血再灌注损伤具有保护作用,在建立脑缺血再灌注模型基础上,侧脑室注射IL8单抗,通过观察脑梗死表1各组大鼠脑梗死灶体积及TUNEL、Bcl2及Bax阳性细胞数分组鼠数梗死灶体积(mm3)TUNELBcl2Bax生理盐水对照组6210.26±25.5845.82±7.0322.97±5.6470.16±8.54IL8单抗0.5μg组6207.25±28.5944.92±7.1124.46±6.3868.26±8.43IL8单抗1μg组6166.29±31.7338.87±7.1…     

烟草烟雾对大鼠脑血管内皮细胞细胞间黏附分子-1表达及脑梗死体积的影响

目的　研究烟草烟雾对大鼠脑血管内皮细胞超微结构 ,细胞间黏附分子 1(ICAM 1)mRNA、ICAM 1表达及大脑中动脉梗死体积的影响。方法　建立大鼠吸烟模型 ,原位杂交及免疫组化检测大鼠脑血管内皮细胞ICAM 1mRNA、ICAM 1的表达 ;建立大鼠左侧大脑中动脉梗死模型 ,测定梗死灶体积占同侧大脑半球体积百分比 ;电镜观察内皮细胞超微结构的改变。结果　 (1)吸烟大鼠脑血管内皮细胞ICAM 1mRNA、ICAM 1表达增加 ,脑梗死灶体积增加 (长期大量吸烟组为4 3 7%± 3 7% ,对照组为 2 7 9%± 1 5 % ,P <0 0 5 ) ;内皮细胞超微结构改变显著。 (2 )戒烟大鼠脑血管内皮细胞ICAM 1mRNA、ICAM 1表达及脑梗死灶体积减小 ,内皮细胞超微结构病理改变明显恢复。结论　烟草烟雾使大鼠脑血管内皮细胞ICAM 1mRNA、ICAM 1表达及大鼠脑梗死灶体积增加 ,二者间存在剂量 效应关系。     

脑缺血大鼠再灌注后脑皮质中PC1mRNA及蛋白质的表达

背景：前蛋白转化酶（Proprotein convertases,PCs)是神经肽的加工酶,前蛋白转化酶1（Proprotein convertase 1,PC1) 是PCs家族中的一员, PC1加工许多神经肽及肽类激素,已有研究表明PC1对应激高度敏感,但尚不明确脑缺血后PC1的变化。 目的: 观察局灶性脑缺血后大鼠脑皮层内PC1mRNA 及PC1的经时表达变化。 设计：完全随机设计,对照实验研究。 地点和材料：美国俄勒冈州波特兰Robert S. Dow 神经生物研究室, Legacy 临床研究与技术中心,所有动物实验均遵照国家健康指南中实验室动物养护及使用制度,雄性健康Sprague–Dawley 大鼠 (250 g--300 g) 购自美国Wilmington的Charles River实验室。 干预: 用大脑中动脉阻塞(MCAO)的方法建立短暂性局灶性脑缺血模型,用原位杂交及免疫组化双标法分析假手术对照组大鼠及100分钟MCAO后再灌注4小时、8小时、16小时及24小时大鼠脑皮层内PC1mRNA及PC1表达的变化。 主要观察指标: 100分钟MCAO后再灌注4小时、8小时、16小时及24小时大鼠缺血脑皮层、非缺血脑皮层内及假手术对照大鼠脑皮层内PC1mRNA及PC1表达的变化。 结果: 假手术对照大鼠及100分钟MCAO后再灌注4小时、8小时、16小时及24小时大鼠缺血侧及非缺血侧脑皮层表达PC1mRNA的细胞数分别是每高倍镜视野35.6 ±4.3及36.2±3.6,29.6±5.1及36.1 ±4.1,30.1±4.6及35.8±4.3,28.2 ±4.9及35.9 ±5.2,18.2±5.3及35.6±4.9,而表达PC1的细胞数分别是每高倍镜视野28.2 ±3.3及28.8±4.1,17.8±4.2及29.1±3.6,17.6±4.6及28.7±3.6,18.1±3.9及29.3 ±4.5,22.3±3.2及29.0±4.1。缺血侧脑皮层PC1mRNA及PC1的表达在再灌注4小时、8小时及16小时逐渐下降,在再灌注24小时时下降最显著,缺血侧脑皮层PC1表达水平在再灌注24小时较再灌注4小时、8小时及16小时增高,而此时PC1mRNA表达水平仍低。 结论: 局灶性短暂脑缺血可影响大鼠缺血脑皮层内PC1mRNA及PC1的表达,缺血性应激可调节PC1。     

左旋多巴诱发异动症大鼠纹状体区P38及GAP-43表达的变化

目的　观察帕金森病(Parkinson disease, PD)大鼠经慢性间断性左旋多巴(levodopa,L- dopa)治疗后纹状体区域突触功能的变化。方法　 6 羟多巴胺 (6 OHDA)脑立体定位注射制备偏侧PD大鼠模型,复方L dopa甲酯治疗4周[按体重20 mg/(kg·d),分2次进行腹腔注射]建立异动症(levodopa induced dyskinesias,LID)大鼠模型,采用免疫组化方法检测 PD组和 LID组纹状体内突触素(synaptophysin, P38)及生长相关蛋白(growth associated protein, GAP 43)的表达。结果　 PD 大鼠损毁侧 P38 免疫反应阳性颗粒的数密度[(0. 002 1±0 000. 5)个/μm2]和面密度(0. 045±0.01)均明显高于健侧[分别为(0 .015 0±0. 000 6)个/μm2, (0 027±0 .009)](P<0 .01),GAP- 43阳性颗粒面密度(0. 015±0. 000 3)高于健侧(0. 01±0 .000 27)(P<0. 05);LID大鼠经L dopa治疗后两者表达进一步增多,与PD组大鼠损毁侧相比差异有显著性(均 P<0 .05)。结论　慢性L dopa治疗进一步促进了PD大鼠纹状体区域P38及GAP -43的高表达,可能涉及皮质纹状体病理性长时程增强的突触前机制,提示皮质 纹状体环路的突触可塑性与LID发生密切相关。     

脑缺血再灌注神经干细胞原位激活的研究

目的 探讨大鼠局灶性脑缺血再灌注后不同时间、不同脑部位神经干细胞(NSC)原位激活的变化规律。方法 建立一侧大脑中动脉闭塞缺血再灌注模型,用5-溴脱氧尿苷(BrdU)标记脑内增殖细胞,免疫组化(SP法)技术检测大鼠缺血再灌注不同时间段缺血周边皮质、双侧侧脑室下区(SVZ)、海马齿状回下区(SGZ)具有增殖能力细胞BrdU表达变化。结果 对照组脑组织双侧SVZ、SGZ可见少量BrdU阳性标记细胞;单纯脑缺血2 h组脑组织BrdU阳性细胞数未见明显增加;再灌注3天组,缺血侧皮质、双侧SVZ和SGZBrdU阳性细胞明显增多(P<0.05),7天时达到高峰(P<0.001),11天时下降,且缺血侧与对侧相比,双侧SVZ呈对称分布,而SGZ以缺血侧增加为主(P<0.05)。结论 一侧大脑中动脉闭塞缺血再灌注可致成年大鼠脑内NSC原位激活,且NSC增殖于缺血后1周达到高峰,激活部位以双侧SVZ、缺血侧海马和周边皮质为主。     

Mechanisms of the suppression of the nociceptive reflex of the opening of the mouth during stimulation of the structures of the limbic brain

The comparative effectiveness of the inhibitory influence of tetanic stimulation of hypothalamus, amygdala and limbic cortex on EMG-response of m. digastricus evoked by electrical stimulation of tooth pulp nociceptive afferents was studied in cats anesthetized with a mixture of chloralose and nembutal. It was found that inhibition of the EMG-component of the jaw-opening reflex is most pronounced in case of stimulation of medial and lateral region of the hypothalamus, the inhibitory effect of central and medial nuclei of the amygdala is less pronounced and the effect of the limbic cortex is the weakest. It was shown that the mechanism of the antinociceptive effect of tetanic stimulation of the hypothalamus is not related to the concomitant increase of the blood pressure. After stabilization of the blood pressure the suppressive effect of the hypothalamus remains without changes, that points out to a direct, primary, not baro-afferent mechanism of the inhibition of the activity of nociceptive neurons of the trigeminal sensory nuclei. Noradrenaline, injected intravenously, induced a large increase of the blood pressure accompanied by a pronounced inhibition of the pain reflex. Angiotensin causes the same degree of blood pressure elevation without changes in the amplitude of the EMG-response of the pain reflex. Hypothalamic and noradrenergic mechanisms for control of pain sensitivity are discussed.     

药物治疗与合并认知行为治疗对强迫症疗效的比较

目的探讨认知行为心理治疗(CBT)在强迫症(OCD)患者各亚型治疗中的有效性和规律性。方法本研究为临床对照研究。符合入组标准的强迫症患者按患者自愿原则分为两组,治疗观察3、6、12个月。疗效评定分别运用Yale-Brown强迫量表,自拟的自评好转程度量表和临床疗效评定。结果认知行为心理治疗合并药物治疗组31例,临床有效率70.9%,其中治愈率1.8%。单纯药物治疗组24例,临床有效率33.3%。Yale-Brown强迫量表和自评量表得分在6个月和12个月两组有显著差异(P<0.05)。其中强迫症亚型(怕脏型、反复检查型和反复担心型)的疗效比较,怕脏型在治疗3个月末两组间自评量表评分有显著性差异(P<0.05);反复担心型在治疗6个月末两组间Yale-Brown强迫量表总分有显著性差异(P<0.05);反复检查型两组间无统计学差异。结论认知行为心理治疗合并药物治疗强迫症的疗效明显优于单纯药物治疗。强迫症的亚型在治疗中的有效性次序为:反复担心型>怕脏型>反复检查型。     

Characteristics of the sympathetic innervation of the nictitating membrane and of the vasculature of the nose and tongue of the cat

Summary Vasomotor responses from the nasal mucosa and tongue, and contractions of the nictitating membrane, were recorded on stimulation of the cervical sympathetic or internal carotid nerves.Preganglionic sympathetic nerve fibres which elicited a membrane response possessed a lower threshold than those which evoked nasal vasoconstriction, while the latter displayed a lower threshold than fibres which evoked tongue vasoconstriction. The sympathetic vasodilator fibres to the tongue, whose activity was revealed after-receptor blockade, had a similar threshold to the vasoconstrictor fibres.Membrane contraction, nasal vasoconstriction and occasionally tongue vasoconstriction could be evoked by stimulating the internal carotid nerve. The postganglionic fibres innervating the nasal mucosa had a similar threshold to those of the nictitating membrane, which may indicate that there are small myelinated fibres innervating the mucosa.The preganglionic compound nerve action potential had four major components, S₁–S₄. S₁, S₂ and usually S₃ fibres were associated with membrane contraction; S₂, S₃ and sometimes S₁ fibres were associated with nasal vasoconstriction; and S₃, usually S₂ and occasionally S₁ fibres were associated with vasoconstriction in the tongue. It is concluded that each of these three groups of nerve fibres, but not S₄ fibres, may include fibres associated functionally with the three effectors.There was a considerable difference between the relative amplitude of the responses of the three effectors elicited by stimulation of the cervical sympathetic nerve at frequencies between 0.2 and 2 Hz. Vasoconstrictor responses were relatively larger than membrane contractions suggesting differences in the mechanisms of neurotransmission at the neuroeffector junctions.     

Development of the projection from the nucleus of the brachium of the inferior colliculus to the superior colliculus in the ferret

Neurons in the deeper layers of the superior colliculus (SC) have spatially tuned receptive fields that are arranged to form a map of auditory space. The spatial tuning of these neurons emerges gradually in an experience-dependent manner after the onset of hearing, but the relative contributions of peripheral and central factors in this process of maturation are unknown. We have studied the postnatal development of the projection to the ferret SC from the nucleus of the brachium of the inferior colliculus (nBIC), its main source of auditory input, to determine whether the emergence of auditory map topography can be attributed to anatomical rewiring of this projection. The pattern of retrograde labeling produced by injections of fluorescent microspheres in the SC on postnatal day (P) 0 and just after the age of hearing onset (P29), showed that the nBIC-SC projection is topographically organized in the rostrocaudal axis, along which sound azimuth is represented, from birth. Injections of biotinylated dextran amine-fluorescein into the nBIC at different ages (P30, 60, and 90) labeled axons with numerous terminals and en passant boutons throughout the deeper layers of the SC. This labeling covered the entire mediolateral extent of the SC, but, in keeping with the pattern of retrograde labeling following microsphere injections in the SC, was more restricted rostrocaudally. No systematic changes were observed with age. The stability of the nBIC-SC projection over this period suggests that developmental changes in auditory spatial tuning involve other processes, rather than a gross refinement of the projection from the nBIC.     

A contribution to the study of the architecture of the autonomic nervous system of the digestive tract of the rat

Summary The distribution of aminergic and non-aminergic nerve fibres to the different constituents of the wall of the digestive tract in various regions is described. Aminergic fibres synapse with all nervous perikarya. Densely interlacing networks of nerve fibres are found in both layers of the tunica muscularis and in the lamina muscularis mucosae. A finely meshed plexus is observed in relation to the wall of the blood vessels in the wall of the gut. There are many fibres connecting the muscular and the vascular plexus. No nerve fibres have been observed in direct relation to the epithelium.The functional implications of these findings are discussed.