实验性猕猴椎基底动脉粥样硬化的研究

本研究用高脂饮食喂养猕猴,造型期17个月,取其椎动脉颅外及颅内段、基底动脉和大脑后动脉作光镜、扫描电镜观察。结果发现颅外段椎动脉粥样硬化损害程度较颅内段重,其脂斑数目多,面积大;颅内段也可见大小不等、形态多样的脂斑,但大部分内膜仍较正常;基低动脉损害较轻,内膜仅含2—3层泡沫细胞,但中膜平滑肌细胞已开始变性;大脑后动脉未见有脂斑,但有弥漫性内膜增厚,且超过了中膜的厚度。本研究结果与我们先前报道的同一模型的颈动脉系统比较,发现颈动脉系统的损伤程度更重于椎基底动脉系统,这和人类脑动脉粥样硬化多发生在颈内动脉和Willis环的规律一致,因此我们认为猕猴可作为研究脑动脉粥样硬化的十分理想的动物模型。

A Study of Experimental Vertebral—basilar Atherosclerosis in Rhesus Monkeys

Atherosclerosis was produced in rhesus monkeys by feeding them atherogenic diet for 17 months. Using both light and scanning electron microscopy we examined intracranial and extracranial segments of vertebral,basilar and posterior cerebral arteries.The histologic lesions were noted in all arteries of test animals but in different degrees of severity.Extracranial segment showed more fatty plaques than intracranial segment.The intima of basilar artery contained groups of foam cells forming two to three layers and medial smooth muscle cells were poor in myofilaments,Large fat vacuoles were often seen in them.Intercellular spaces between medial smooth muscle cells were enlarged.The diffuse intimal thickening was detected in posterior cerebral artery.The intima was thicker than the underlying medi- a.This study together with our previous studies on carotid system suggest that the severity of atherosclerosis lesions in carotid system was more than that of vertebral—basilar arteries.The pattern of distribution,extent and type of lesions resembled those seen in man.From the present investigation it can,therefore,be concluded the atherosclerosis of the cerebral arteries can be produced experimen- tally in this animal model.