A Historical Study on Atherosclerosis WHHL Rabbit with Reference to Carotid Arteries and Intracranial Arteries

为了探讨WHHL兔动脉粥样硬化的形成过程，作者对双侧颈动脉和颅内动脉，特别是基底动脉进行了组织学研究。此外，还检测了血清胆固醇和甘油三酯水平。本实验选用2月龄至龄健康新西兰兔37只，组织学观察发现2月龄以上兔颈动脉内膜增厚，发生率为92%。相反，无颅内动脉参与内膜增厚。WHHL兔动脉粥样硬化的特点是内膜增厚，主要以泡沫细胞为主，并伴有平滑肌细胞和弹力纤维的增殖。而内弹力板相对保存较好。动脉粥样硬化的附加特征是胆固醇结晶和钙化。这些发现被认为与人类常见的动脉粥样硬化是一致的。颈动脉内膜增厚的地形图分布似乎与胆固醇水平和甘油三酯水平无关。兔至20个月龄时，动脉分叉内膜逐渐增厚。20月龄以上兔几乎所有节段均有内膜增厚。总之，作者认为WHHL兔是L研究颈动脉粥样硬化的合适动物模型，但另外一些因素(S)可能是诱发颅内动脉粥样硬化的必要因素。

In an attempt to investigate atherosclerosis developing in WHHL rabbits, the author carried out a histological study on bilateral carotid arteries and intracranial arteries, particularly those present in the basilar area. In addition, serum level of cholesterol as well as triglyceride was measured. Thirty-seven WHHL rabbits in a range of 2-to 64-month-old were used in this experiment.Histologically, intimal thickening of carotid arteries was observed in rabbits above 2-month-old, and the incidence was 92%. In contrast, no intracranial arteries were involved with intimal thickening. Atherosclerosis of WHHL rabbits was characterized by intimal thickening which consisted mainly of foam cells and proliferation of smooth muscle cells as well as elastic fibers. However, internal elastic lamina was relatively preserved. The atherosclerosis had cholesterine crystals and calcification as additional features. A constellation of these findings was considered to be in keeping with atherosclerosis commonly seen in humans.A topographic distribution of the intimal thickening of carotid arteries seemed to have no correlation with the cholesterol level as well as the triglyceride level. Progressive thickening of the intima in bifurcations was demonstrated as the rabbits aged upto 20-month-old. In the rabbits above 20-month-old, almost all segments had intimal thickening. The lesion progressed from the bifurcations along a blood flow.In conclusion, the author considers that WHHL rabbit is a suitable animal mode l to study atherosclerosis of carotid arteries ; however, some additional factor(s), presumably such as a hypertensive state, seems to be necessary to induced the atherosclerosis in intracranial arteries.