[A morphological study of the lesioned carotid artery--comparison with WHHL rabbit and Japanese white rabbit]

It is necessary for a neurosurgeon to know the course of repair of vascular injury caused by the procedure of an operation. And further more, it is very important to understand how existence of hypercholesteremia would affect it. Injuries of operations were caused to carotid arteries of Watanabe heritable hyperlipidemic (WHHL) rabbit and a morphological study of the course of repair was made. Japanese white rabbit (JWR) were treated exactly same as WHHL, and their course of repair was compared and examined as control. One week after operation, both WHHL rabbit and JWR showed edematous thickening of a intima, increase in grade of thickening which was continued until two of three months after operation was observed, however gradually decrease thereafter. In case of WHHL rabbit, thickened intima at suture portion was formed by smooth muscle cells migrated from media. Foamy cells were not observed here. The grade of thickening of WHHL rabbits was lower than that of JWR, and that WHHL rabbits tended to show slower change of elastofibrosis in thickened intima rather than JWR. It was considered that the smooth muscle cells of WHHL rabbit has a poor activity naturally.