幼儿海马血管构筑研究

本文采用色素明胶灌注后肉眼及光镜观察,铸型扫描及图像分析对31例幼尸的海马血管构筑进行了研究.人海马血管主要来源于大脑后动脉,分海马前、中、后动脉,由其进一步发出海马内侧及外侧横行动脉供应海马本部与齿状回.海马内部存在着广泛的毛细血管前徵血管吻合和毛细血管网.海马前部毛细血管密度高于后部;内部以CA_2,CA_3区锥体层密度最高.扫描电镜下可见徵静脉与徵动脉以1∶4的关系构成徵血管单位,并见毛细血管前后括约肌.     

大鼠海马的血管构筑

用血管铸型法、动－静脉连续灌注法、组织化学ＤＡＢ法和生物体视学方法研究大鼠海马的血管构筑。结果表明：大鼠海马由大脑后动脉的分支──海马纵动脉供血，后者发出数支耙状分支进入海马。根据分支分布部位可分为海马内、外侧横动脉，它们经逐级分支移行为毛细血管，供应海马各区及齿状回。海马内毛细血管的分布具有与海马皮质分层相对应的层次性。海马各区及齿状回毛细血管的长度密度为齿状回＞ＣＡ＿３＞ＣＡ＿４＞ＣＡ＿２＞ＣＡ＿１。海马具有内侧及外侧两个静脉系统。本文对海马的血管构筑及其缺血敏感性和选择性损伤进行了讨论。     

海马内部血管构筑——硷性磷酸酶显示法

本文用硷性磷酸酶示内皮法,对15例SD系大鼠海马内部的微血管构筑在光镜下进行了观察。结果显示大鼠海马内部各区各层的血管分布与其神经组织构筑有明显的对应关系。即从血管的排列可辨认海马内部各层。CA1区锥体层血管密度最低,而其腔隙分子层血管密度最高,辐状层血管相互平行排列且与海马裂垂直。在CA2及CA3区交界处有恒定的小动脉及其分支出现,CA1与CA2区移行处锥体层硷性磷酸酶反应可见明显差异。此外还观察到丰富的血管吻合,微动脉及微静脉的吻合支可通过海马的几层或全层。并且讨论了神经组织构筑与血管排列之间的关系。     

人海马区血管显微解剖

目的：探讨人海马血供的形态学特征，为海马区血管介入或外科手术的入路提供理论依据。方法：对固定的成人尸体海马区进行显微解剖，追踪动脉来源和分布，并测量各动脉的口径。结果：海马血供具有多源性。海马前区、海马头、海马体、海马尾、海马后区分别由多种来源动脉供应，但动脉主要来自大脑后动脉及其分支(83．85％)和脉络膜前动脉(16．15％)。口径自0．31mm到0．77mm不等。结论：海马血供具有多源性。主要来自大脑后动脉及其分支和脉络膜前动脉。介入时要到达脉络膜前动脉或大脑后动脉才能有效地改善海马血供。海马内侧有许多大血管和重要的脑结构，经颞叶切除海马才是安全可靠的入路。     

海马皮质厚度和血管发育研究

用碱性磷酸酶染色,HE染色及墨汁灌注法,在光镜下观察30例(60侧)6个月胎儿至6岁儿童新鲜尸体大脑海马皮质厚度,皮质动脉分布,皮质动脉管径,毛细血管密度和管径,结果表明:海马皮质厚度,血管分布,血管密度和管径均随年龄增长而增加,并且均以出生后变化明显。     

海马皮质厚度和血管发育研究

用碱性磷酸酶染色，ＨＥ染色及墨汁灌注法，在光镜下观察３０例（６０侧）６个月胎儿至６岁儿童新鲜尸体大脑海马皮质厚度，皮质动脉分布皮质动脉管径，毛细血管密度和管径，结果表明，海马皮质厚度，血管分布，血管密度和管径均随年龄增长而增加，并且均以出生后变化明显。     

癫痫大鼠海马微血管的扫描电镜观察

应用血管铸型扫描电镜法，对听源性癫痫大鼠海马的微血管进行了观察。结果：癫痫大鼠海马的微血管走行与正常大鼠相似，但其微血管形态与正常大鼠相比有明显差异。癫痫大鼠海马微动脉的内皮细胞核压迹分布无一定规律，微动脉内表面凹凸不平。癫痫大鼠海马的小管微动脉环平行平滑压肌压迹急剧增多。     

兔海马的血管构筑

用血管铸型扫描电镜术，动－静脉连续灌注法、组织化学ＤＡＢ法和生物体视学方法研究了兔海马的血管构筑。结果如下：兔海马由大脑后动脉和脉络膜前动脉供血。前者的初级分支发出一系列耙状分支进入海马，根据进入海马的部位可分为扇面动脉和海马背动脉。它们更发出分支至海马各区和齿状回。大脑后动脉经五级分支形成毛细血管网。海马各区和齿状回的毛细血管平均密度ＣＡ３＞ＣＡ４＞ＣＡ２＞齿状回＞ＣＡ１。海马静脉与动脉不完全伴     

自发性高血压鼠脑底动脉降钙素基因相关肽能神经纤维的分布

应用免疫组织化学ABC法和神经交点计数技术,观察了10只自发性高血压大鼠和10只正常血压大鼠脑底动脉降钙素基因相关肽(CGRP)能神经纤维的分布。结果证明:在自发性高血压鼠的大脑前动脉、大脑中动脉、大脑后动脉和基底动脉壁上均可见CGRP免疫反应阳性纤维,纤维呈细曲线状,多呈网状走行;与正常血压鼠脑底血管同名动脉比较,其密度明显减少。正常血压鼠脑底血管CGRP能神经纤维多呈环形走行。高血压鼠的CGRP能神经纤维的分布随着高血压的发生而明显减少,提示CGRP能神经纤维的减少与高血压的发生、发展具有一定的关系。     

大鼠纹状体血管构筑及增龄变化

目的:研究纹状体血管构筑及其微血管的增龄变化,为探讨纹状体易卒中机制、揭示脑血管病发病机理提供参考资料。方法:运用墨汁明胶灌注、血管铸型、透明、透射电镜等方法观测了三组不同月龄Wistar大鼠纹状体的血管。结果:大鼠纹状体主要由颈内动脉、大脑中动脉、大脑前动脉供血,它们的中央支多以直角发出。尾壳核内部微血管网稠密,与神经纤维、神经细胞之间形成蜂巢状结构。苍白球血管网较稀疏,内囊血管网较苍白球更为稀疏,三者间界限清晰。>24月龄大鼠纹状体毛细血管基膜增厚、内皮细胞固缩、线粒体、内质网等细胞器减少。结论:大鼠纹状体的血供与人的相似,其特殊的形态及增龄变化可能与该区易发生脑血管病有关。     

Thalamic arterial pattern: An endocast and scanning electron microscopic study in normotensive male rats

Rat cerebral vasculature serves as a model for study of the pathophysiology of stroke in humans. Human thalamic anteries show a high incidence of stroke. The objective is to describe the thalamic arterial vascular pattern in normotensive male rats as the initial step for quantitative histochemical studies of enzyme activities in the walls of these vessels. Intracardiac injections of methyl methacrylate monomer provide detailed vascular endocasts. The thalamic vascular bed defined by in situ dissection, serial reconstruction, and light and scanning electron microscopy of endocasts contained four groups of vessels: (1) ventral medial thalamic arteries, (2) thalamic branches from the posterior cerebral artery, and (3) ventral lateral and (4) ventral anterior thalamic arteries. Thalamic vessels are muscular arterioles that, after three to four bipinnate branches, feed into a continuous capillary bed (no loops). The parent vessels and their subsequent branches have been evaluated in terms of their mean internal diameters, mean interbranch intervals, and branch angles. The arterial patterns to rat and human thalami are very similar, with the exception of the anterior choroidal artery which is missing in the rat. The branches supplying the thalamus in both the rat and human are closely associated with the circle of Willis; however, the constituent parts of the circle in rat vary from the pattern in human brain. The rat thalamic arteries show morphological features similar to those seen in the stroke-prone ganglionic arteries in the human basal ganglia.     

Regional and species differences in vascular reactivity to extracellular potassium

In-vitro vasoreactivity to extracellular potassium (Ko+) was tested in isolated human pial and mesenteric arteries as well as basilar and mesenteric arteries from rabbits and rats. Contractions were induced by stepwise increases in [K+]o and were measured isometrically with a force-displacement transducer, in small-volume organ baths. Significant differences between species as well as between regions were found. The threshold of [K+]o for eliciting contraction in human cerebral arteries in hyperosmotic solutions was 10 mM, in rabbit cerebral arteries 17 mM and in rat cerebral arteries 27 mM. The threshold concentration for contraction in mesenteric arteries was significantly higher compared to cerebral arteries in humans and rabbits, but lower in rats: 20 mM in humans, 26 mM in rabbits and 25 mM in rats. In all species the contractile amplitudes were significantly higher in both cerebral and mesenteric arteries when [K+]o was increased under isotonic conditions in the buffer solution than when hyperosomolality was created. This difference increased with increasing hyperosmolality. In hyperosmotic solutions, the EC50 for [K+]o was lower in cerebral and mesenteric arteries from man than in vessels from rabbit and rat. When the solutions were isotonic, this pattern was seen only in mesenteric arteries. It is concluded that significant species and regional differences in vascular responses to [K+]o exist. Considering that [K+]o is increased in cerebral ischaemia, the observed significantly lower threshold for K+-induced contractions in human cerebral arteries may be of importance, especially in human cerebral ischaemic events.     

一种新的老年期痴呆大鼠模型的研究

目的:建立一种新的用于老年期痴呆发病机制与防治研究的老年期大鼠模型。方法:雄性Wistar大鼠,双侧颈总动脉永久性结扎(2VO)并腹腔注射D-半乳糖(D-gal)6周(60mg/kg/天),制备老年期痴呆大鼠模型。采用神经电生理(事件相关电位)检测,脑组织切片Bielschowsky改良法银染色、HE染色、海马乙酰胆碱酯酶(AchE)活性检测等方法比较模型鼠和正常对照鼠的差异。结果:与对照组相比,模型组鼠出现白内障改变及明显P300潜伏期延长、脑内AchE活性降低、海马神经元变性、固缩、坏死及神经纤维紊乱等变化。结论:双侧颈兔动脉永久性结扎加D-gal腹腔注射制备的大鼠模型模拟了人类老年期痴呆的发病特点,可用于血管性痴呆、阿尔茨海默病等老年期痴呆的形态、病理生理变化机制及防治措施的基础与临床研究。     

Some observations on the cerebral arterial circles of mink (Mustela vison)

With the exception of a brief allusion to an unidentified species of Mustela with regard to cerebral vascular studies by de Vriese ('05), major information concerning the circle of Willis in mink was nonexistent until the present investigation. Brains of mink in which the cerebral arterial circles were injected with latex and subsequently hardened in formalin, revealed the primary cerebral arterial anastomosis to be ring-like in form; all of the component vessels were patent and well formed, none was attenuated or string-like. Some of the more prominent findings included: (1) a predominance of asymmetric divergence of the posterior communicating arteries separating from the bifurcating basilar artery; (2) the presence of a posterior intercommunicating artery in all of the specimens; (3) the occasional doubling of the superior cerebellar and the posterior cerebral arteries; (4) deeply placed internal cerebral loops forming secondary arterial anastomoses between some penetrating vessels in the caudal region of the circle; other loops interconnected other penetrating vessels in the rostral region of the circle; (5) blood channels forming an intercarotid anastomosis traversed the pia mater; (6) the presence of a penetrating artery adjunctive to the recurrent artery of Heubner; (7) anastomoses between the internal and the external ophthalmic arteries, and between the internal and the external olfactory arteries forming collateral channels of communication between the intracranial and the extracranial circulations; (8) the occasional presence of an anterior communicating artery supplementing the commonly occurring azygos anterior cerebral artery which continued as a single vessel throughout its extent; (9) unjoined anterior cerebral arteries in one animal which was exceptional.     

自发性高血压鼠脑底动脉血管活性肠多肽能神经纤维的分布

目的 探讨肽能神经对高血压鼠脑血管的神经源性调节的形态学基础。方法 应用免疫组织化学ＡＢＣ法和图介分析技术，观察了１０只自发性高血压鼠（ＳＨＲ）和１０只正常血压鼠脑底动脉血管活性肠多肽能神经纤维的分布。结果 在自发性高血压鼠脑的大脑前动脉、中动脉、后动脉和基底动脉及其分支均可见棕褐色的免疫反应性纤维，纤维似细曲线状，多呈网状分布，与正常血压鼠同一部位脑底动脉血管壁上的免疫反应性纤维密度比较，自发性高血压鼠大脑前动脉、中动脉和后动脉的免疫反应性纤维明显减少。结论 高血压鼠脑底动脉血管活性肠多肽能神经纤维密度的减少，提示在ＳＨＲ脑血流的自动调节作用中，由于非交感性血客扩张神经减少，导致神经源性血管扩张作用减弱，交感神经活性相对增加，表明血管活性肠多肽神经在高血压鼠脑血管的神经源性调节中起着重要的作用。