抑制基质金属蛋白酶-9可延长大鼠脑栓塞后尿激酶溶栓时间窗

目的研究基质金属蛋白酶抑制剂强力霉素和三七皂甙对大鼠脑栓塞后不同时间尿激酶静脉溶栓效果及并发症的干预作用,评价基质金属蛋白酶抑制剂对尿激酶溶栓治疗时间窗的干预效果。方法采用大鼠自体血栓塞大脑中动脉闭塞(MCAO)模型,分别用免疫组织化学法、TTC染色、伊文氏蓝法和分光光度计法对基质金属蛋白酶-9(MMP-9)、脑梗死体积、血脑屏障通透性和脑出血量进行检测。结果相应时间段尿激酶(UK)溶栓组与缺血对照组比较MMP-9表达显著增高,血脑屏障通透性和脑出血量均有增加趋势,以12h UK组明显;6h UK组较缺血对照组脑梗死体积明显降低。强力霉素和三七皂甙联合尿激酶治疗的各组与相应时间点单用尿激酶组比较MMP-9表达显著降低,脑梗死体积明显下降,血脑屏障通透性和脑出血量均有改善。结论基质金属蛋白酶抑制剂联合溶栓治疗,提高溶栓疗效,减轻溶栓后血脑屏障破坏和出血性转化,可能有延长溶栓治疗时间窗的作用。     

强力霉素对溶栓脑缺血大鼠血脑屏障通透性的影响

目的观察强力霉素对脑缺血不同时间尿激酶溶栓大鼠血脑屏障通透性的影响,评价其对溶栓后出血性转化的干预效果。方法采用大鼠白体血栓塞大脑中动脉闭塞（MCAO）模型,分别测定MMP-9表达水平、血脑屏障通透性、恼出血量和出血发生率。结果各时间点尿激酶溶栓治疗使MMP-9表达增加,血脑屏障通透性、脑出血量和出血发生率较对照组增加,且溶栓时间越晚增加越明显;强力霉素联合尿激酶溶栓组与相应时间点尿激酶溶淦组比较MMP-9表达水平和血脑屏障通透性显著降低,而脑出血量和出血发生率均有下降趋势。结论强力霉素联合尿激酶溶栓治疗可降低脑缺血大鼠溶栓后MMP-9高表达,减轻不同时间点尿激酶溶栓后血脑屏障破坏导致的颅内出血性转化。     

基质金属蛋白酶-9在脑梗死溶栓治疗中作用的研究进展

在急性脑梗死治疗中,静脉用重组组织型纤维蛋白溶酶原激活剂(rt-PA)溶栓治疗可触发基底金属蛋白酶-9(MMP-9)的表达上调,进而破坏血脑屏障(BBB)的完整性,增加溶栓的风险。MMP-9的早期抑制可通过抑制rt-PA与脑实质的结合来维持卒中后BBB的完整性,从而减少出血并发症。因此MMP-9可作为一种预防溶栓中的脑出血,延长治疗时间窗的治疗靶点。本文综述近年MMP-9在脑梗死溶栓中的研究,为进一步探索扩大溶栓治疗窗的策略提供依据与思路。     

依达拉奉对尿激酶溶栓大鼠脑组织基质金属蛋白酶-9表达及出血转化的影响

目的探讨依达拉奉对尿激酶溶栓大鼠脑组织基质金属蛋白-9(MMP-9)表达及脑出血性转化的影响。方法健康雄性Sprague Dawley(SD)大鼠制作大鼠自体血大脑中动脉栓塞模型,制作成功后随机分成3组:尿激酶组、脑缺血组、尿激酶+依达拉奉组;每组20只,另加20只为假手术组。取脑组织进行病理学检查并用免疫组化技术检测MMP-9表达,RT-PCR检测MMP-9mRNA表达。结果各组大鼠脑组织病理学结果:尿激酶组中7只发生脑出血,脑缺血组仅1只有红细胞漏出血,尿激酶+依达拉奉组4只发生脑出血,且出血体积较尿激酶组明显减少。尿激酶组中MMP-9在脑组织中高度表达,尿激酶+依达拉奉组表达相对减少,与脑缺血组及尿激酶组比较,差异有统计学意义(P<0.05)。假手术组大鼠脑组织中微量表达。MMP-9mRNA表达与MMP-9在各组中表达一致。结论依达拉奉能显著降低尿激酶溶栓大鼠脑组织中MMP-9mRNA及MMP-9蛋白表达,并可能降低溶栓后出血转化率。     

依达拉奉对大鼠脑梗死溶栓治疗后MMP-9表达的影响

目的研究依达拉奉对大鼠脑梗死溶栓治疗后脑组织中MMP-9表达及血脑屏障的影响,探讨依达拉奉对脑梗死溶栓治疗后再灌注损伤的保护机制。方法采用SD大鼠自体血栓栓塞法制备大脑中动脉闭塞模型,并将SD大鼠随机分为假手术组、尿激酶溶栓治疗组(UK)、尿激酶+依达拉奉治疗组(UK+ED),12h后分别以免疫组织化学法和比色法对SD大鼠脑组织中MMP-9表达水平和伊文思蓝含量进行测定。结果与尿激酶溶栓治疗组相比,尿激酶+依达拉奉组SD大鼠缺血侧脑组织MMP-9表达水平和EB含量均显著降低,差异具有统计学意义(P值均<0.01)。结论依达拉奉可能通过下调MMP-9表达,减轻血脑屏障的破坏,减轻溶栓后脑缺血再灌注损伤。     

D-阿洛糖对小鼠脑缺血再灌注血脑屏障影响

目的研究D-阿洛糖对小鼠脑缺血再灌注损伤后血脑屏障的影响。方法 80只小鼠随机分为假手术组(sham组)、脑缺血模型组(MCAO组)、D-阿洛糖治疗组(D-allose组)、生理盐水对照组(NS组)。采用插线法制备小鼠大脑中动脉栓塞(MCAO)模型,尾静脉注射D-阿洛糖(300 mg/kg),运用改良小鼠神经功能缺损评分(m NSS)对小鼠脑缺血再灌注损伤程度评分;通过1%氯化三苯基四氮唑(TTC)染色,计算脑梗面积百分比;运用干-湿重法,测脑含水率;通过伊文思蓝(EB)含量反映血脑屏障的损伤程度;通过HE染色观察脑缺血再灌注损伤后梗死区的病理变化;采用免疫组化检测基质金属蛋白酶9(MMP-9)的表达。结果与MCAO组相比,D-allose可以明显降低小鼠脑缺血再灌注后神经功能缺损评分,减小小鼠脑梗死面积,减轻脑水肿,降低EB含量,减轻脑组织的病理损伤程度,并且明显减少MMP-9表达(P0.05)。结论 D-阿洛糖可以保护小鼠脑缺血再灌注后的血脑屏障,其机制可能与抑制MMP-9的表达有关。     

CD147、MMP-9与釉质型颅咽管瘤侵袭性生长及复发的相关性研究

目的:探讨细胞外基质金属蛋白酶诱导剂( CD147,EMMPRIN)和基质金属蛋白酶-9(MMP-9)在釉质型颅咽管瘤中的表达及其与肿瘤侵袭、复发的相关性。方法:应用免疫组化法对40例釉质型颅咽管瘤标本（原发组24例,复发组16例）中CD147和MMP-9的表达进行检测。结果:CD147在复发组釉质型颅咽管瘤中的总阳性表达率87.5％,明显高于原发组总阳性率37.5％ (P＜0.05);MMP-9在复发组釉质型颅咽管瘤中的总阳性表达率93.7％,明显高于原发组总阳性率41.7％ (P ＜0.05)。复发组釉质型颅咽管瘤中CD147与MMP-9表达呈正相关（P＜0.01）,原发组釉质型颅咽管瘤中CD147与MMP-9表达无明显相关性。结论: CD147与MMP-9可能在釉质型颅咽管瘤侵袭生长和肿瘤复发过程之中扮演着重要的角色,CD147与MMP-9可能成为评价釉质型颅咽管瘤侵袭性生长和复发倾向的重要参考指标。     

颈动脉粥样硬化斑块CD147、MMP-9表达及阿托伐他汀干预的影响

目的 探讨兔颈动脉粥样硬化斑块中CD147、基质金属蛋白酶-9(MMP-9)的表达情况以及阿托伐他汀对其表达的影响.方法 24只新西兰大白兔按随机数字表法分为3组:正常对照组8只,普通饲料喂养16周;余16只给予球囊损伤颈总动脉+高胆固醇喂养,12周后分成模型对照组和阿托伐他汀组(每天2.5 mg/kg阿托伐他汀灌胃),继续喂养4周后给予鲁塞尔氏蛙蛇毒和组胺触发斑块破裂.对斑块进行病理分析,免疫组织化学法检测斑块内巨噬细胞及CD147、MMP-9蛋白表达,逆转录聚合酶链反应(RT-PCR)检测斑块内CD147、MMP-9mRNA表达.结果 药物触发后模型对照组存活的6只兔中有4只发生斑块破裂及血栓形成,阿托伐他汀组存活的7只兔中有1只发生斑块破裂及血栓形成,正常对照组中未见斑块破裂及血栓形成.与模型对照组比较,阿托伐他汀组斑块内巨噬细胞含量明显减少(33.62±3.82vs16.22±2.61),CD147蛋白表达的阳性染色面积比明显降低(29.54±3.03vs14.22±1.63),MMP-9蛋白表达的阳性染色面积比明显降低(21.18±4.75 vs 11.11±1.87),差异有统计学意义(P＜0.05＝.模型对照组和阿托伐他汀组斑块内CD147 mRNA表达水平分别为0.939±0.105和0.426±0.112,MMP-9 mRNA表达水平分别为0.335±0.069和0.135±0.067,比较差异有统计学意义(P＜0.05＝.Pearson相关检验显示斑块中MMP-9蛋白与CD147蛋白表达呈正相关(r=0.669,P=0.001),MMP-9 mRNA与CD147 mRNA表达呈强正相关(r=0.783,P=0.000).结论 CD147、MMP-9表达上调可能参与斑块不稳定的发生机制,阿托伐他汀可能通过下调CD147、MMP-9的表达发挥稳定斑块的作用.     

Guillain-Barre综合征患者B淋巴细胞辅助受体CD22、CD72表达的研究

目的探讨Gu illain-Barre综合征(GBS)患者外周血B淋巴细胞辅助受体CD22、CD72表达及其与GBS病程和病情的关系。方法 36例GBS患者(GBS组)按病程及病情分为急性期亚组与恢复期亚组和轻症亚组与重症亚组,应用流式细胞术检测外周血B淋巴细胞CD22及CD72蛋白表达,比较CD22与CD72蛋白在不同亚组间的表达;并与正常对照组(20人)比较。结果 B细胞数量GBS组[(606±118)个]较正常对照组[(248±92)个]明显升高,CD72+CD19+阳性细胞率[(62.11±9.14)%]较正常对照组[(69.72±11.42)%]明显降低(均P<0.01);CD22+CD19+阳性细胞率两组间差异无统计学意义。GBS组中,急性期亚组[(682±91)个]B细胞数量较恢复期亚组[(550±111)个]明显升高,CD72+CD19+阳性细胞率急性期亚组[(57.79±7.69)%]较恢复期亚组[(68.14±7.58)%]明显降低(均P<0.01);CD22+CD19+阳性细胞率两亚组间差异无统计学意义;重症亚组[(685±116)个]较轻症亚组B细胞数量[(561±96)个]明显升高(...     

Netrin-1对大鼠实验性脑梗死后同侧丘脑血脑屏障保护作用

目的观察脑梗死后同侧丘脑是否出现血脑屏障破坏,Netrin-1对血脑屏障破坏是否具有保护作用及其能否促进神经功能恢复。方法 Sprague-Dawley大鼠36只,建立右侧大脑中动脉闭塞(middle cerebral artery occlusion,MCAO)模型,假手术(sham)组仅暴露右侧大脑中动脉,分为sham组、MCAO+PBS组及MCAO+netrin-1组,每组6只。通过改良大鼠神经功能缺损评分(modified neurological severity scores,m NSS)评价神经功能,造模后第8天及第14天取材,HE染色观察梗死灶,免疫荧光检测occludin及albumin表达与分布,Western blot检测occludin及ZO-1表达水平。结果m NSS评分见予以Netrin-1后于梗死后第8天及第14天评分降低(P0.05)。HE染色见右侧皮层梗死灶。Western blot见梗死后第8天开始出现occludin减少(P0.05),第14天occludin及ZO-1均明显减少(P0.05),免疫荧光见梗死后第8天及第14天occludin减少伴albumin血管外渗出;予以Netrin-1后,western blot及免疫荧光见梗死后第14天occludin增多(P0.05),伴albumin渗出增多,ZO-1无明显变化。结论Netrin-1对大鼠实验性脑梗死后同侧丘脑血脑屏障破坏具有保护作用,并可促进梗死后神经功能恢复。     

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.     

The organization of the connections between the cortex and the claustrum in the monkey

The distribution of labelled cells and of extracellular granules in the claustrum has been studied after injections of horseradish peroxidase in several areas of the neocortex. The frontal and parietal lobes are related to the anterior and posterior halves respectively of the claustrum, and the occipital and temporal cortex to the posterior and inferior margins. Parts of the claustrum related to areas of the cortex in the frontal lobe overlap considerably in the antero-posterior dimension with parts related to widely separated but interconnected areas of the parieto-temporal cortex. Areas of cortex within one lobe which are interconnected are related to parts of the claustrum which overlap in the dorsoventral dimension.     

A projection to the striatum from the medial subdivision of the posterior group of the thalamus in the cat

Injections of wheat germ agglutinin-conjugated horseradish peroxidase in the lateral part of the caudate nucleus or the putamen of the cat result in retrograde thalamic cell-labeling in the rostral extension of the medial subdivision of the posterior group (POM). Autoradiography after [³H]amino acid injection of POM reveals a dense and discontinuous distribution of axons in the lateral half of the caudate and putamen concentrated at their middle rostrocaudal levels. This newly discovered thalamostriatal projection of POM may account for somatosensory activity observed in striatal cells.     

Sexual pheromones and the evolution of the reward system of the brain: the chemosensory function of the amygdala

The amygdala of all tetrapod vertebrates receives direct projections from the main and accessory olfactory bulbs, and the strong similarities in the organization of these projections suggest that they have undergone a very conservative evolution. However, current ideas about the function of the amygdala do not pay sufficient attention to its chemosensory role, but only view it as the core of the emotional brain. In this study, we propose that both roles of the amygdala are intimately linked since the amygdala is actually involved in mediating emotional responses to chemical signals. The amygdala is the only structure in the brain receiving pheromonal information directly from the accessory olfactory bulbs and we have shown in mice that males emit sexual pheromones that are innately attractive for females. In fact, sexual pheromones can be used as unconditioned stimuli to induce a conditioned attraction to previously neutral odorants as well as a conditioned place preference. Therefore, sexual pheromones should be regarded as natural reinforcers. Behavioural and pharmacological studies (reviewed here) have shown that the females' innate preference for sexual pheromones is not affected by lesions of the dopaminergic cells of the ventral tegmental area, and that the systemic administration of dopamine antagonists do not alter neither the attraction nor the reinforcing effects of these pheromones. Anatomical studies have shown that the vomeronasal amygdala gives rise to important projections to the olfactory tubercle and the islands of Calleja, suggesting that these amygdalo-striatal pathways might be involved in the reinforcing value of sexual pheromones.     

Evidence for the collateral innervation of the esophagus and the heart from neurons in the compact formation of the nucleus ambiguus of the rat

We investigated whether the heart receives collateral projections from the neurons which innervate the esophagus with a retrograde double-labeling method using two fluorescent tracers. Following injections of True Blue (TB) into the esophagus and Diamidino Yellow (DY) into the heart, about 21.9% of the labeled esophageal motoneurons in the compact formation of the nucleus ambiguus (AmC) were retrogradely double labeled. No single-labeled cardiac motoneurons were found in the AmC. The present results provide anatomical substrates for the esophagocardiac reflex.     

Role of the paraventricular nucleus in the projection from the nucleus of the solitary tract to the olfactory bulb

Electrophysiological experiments were performed on anesthetized rats to determine the effects of lesions of the paraventricular nucleus on the amplitude of evoked potentials recorded in the periglomerular layer of the olfactory bulb after nucleus of the solitary tract electrical stimulation. Lesions of the paraventricular nucleus enhance the amplitude of both the positive and negative components of the evoked potential in the olfactory bulb. The pathway from the paraventricular nucleus to the olfactory bulb seems to exert a suppressive influence over the projection from the nucleus of the solitary tract to the olfactory bulb under these conditions.     

On the origin of the serotonergic input to the intermediate lobe of the rat pituitary

Single stimulations of the vagina and cervix were performed between proestrus and the first day of diestrus with a stimulator designed to grade the intravaginal penetration of a rod. The percent incidence of pseudopregnancy after this stimulation was exponentially related to the extent of intravaginal penetration and was also affected by the stage of the cycle at which the stimulation was performed. At 10.00 h on proestrus, an exponential increase in the incidence of pseudopregnancy was observed with shallow penetrations, while an exponential decrease was found when deeper penetrations were applied. Such negative exponential correlation had disappeared at 22.00 h on proestrus. At that time, also, some responses were elicited by very shallow penetrations (17 mm) and all the animals responded to penetrations of 20 mm or more. Sensitivity to cervicovaginal stimulation at 10.00 h on estrus was lower than that at 22.00 h on proestrus and it was even lower at 10.00 h on the first day of diestrus. The response to 18 mm of penetration was studied every 3 h between 10.00 h on proestrus and 10.00 h on estrus, and then every 12 h until 10.00 h on the first day of diestrus. This stimulation was usually ineffective to induce pseudopregnancy, except for a brief period encompassing the night between proestrus and estrus, when a peak in the incidence of responses was reached. This peak sensitivity could be advanced following the s.c. administration of 250 and 500 ng of LH-RH at 11.00 h on proestrus. Other doses were ineffective. The peptide (500 ng) was unable to induce pseudopregnancy in rats that received no cervicovaginal stimulation.(ABSTRACT TRUNCATED AT 250 WORDS)     

On the development of the stratification of the inner plexiform layer in the chick retina

This study investigated the development of the subdivision of the chick inner plexiform layer (IPL). The approach included an immunohistological analysis of the temporal and spatial expressions of choline acetyltransferase, of the neural-glial-related and neural-glial cell adhesion molecules (NrCAM and NgCAM, respectively) and axonin-1, and of inwardly rectifying potassium (Kir) channels in 5- to 19-day-old (E5-E19) embryos. Ultrastructural investigations evaluated whether synaptogenesis accompanies the onset of differentiation of the IPL. We found that the differentiation of the IPL started at E9. Distinct cholinergic strata appeared, NrCAM immunoreactivity showed a poorly defined stratification, and Kir3.2 was expressed in the IPL and in the inner nuclear layer. From E10 until late E14, NgCAM- and axonin-1-immunoreactive strata emerged in an alternating sequence from the outer to the inner IPL. During this period, the NrCAM pattern sharpened, and eventually five bands of weaker and stronger immunoreactivity were found. Conventional synapses formed at the beginning of E9, and stratification of the IPL also began on the same day at the same location. Synaptogenesis and stratification followed a gradient from the central to the peripheral retina. The topographic course of differentiation of the IPL generally corresponded to the course of maturation of ganglion and amacrine cells. Synaptogenesis and the expression of G-protein-gated Kir3.2 channels accompanied the onset of stratification. These events coincide with the occurrence of robust and rhythmic spontaneous neuronal activity. The subsequent differentiation of the IPL seemed to be orchestrated by several mechanisms.