Langille B L, Bendeck M P, Keeley F W
Department of Pathology, University of Toronto, Max Bell Centre, Toronto General Hospital, Ontario, Canada.
Am J Physiol. 1989 Apr;256(4 Pt 2):H931-9. doi: 10.1152/ajpheart.1989.256.4.H931.
Adaptive responses of rabbit common carotid arteries were examined after 70-80% reductions in blood flow produced by ipsilateral external carotid artery ligation. These flow reductions elicited growth inhibition of arterial wall tissue in immature rabbits. Specifically, experimental carotid arteries exhibited DNA levels significantly lower, by 35%, than contralateral control arteries 1 mo after external carotid ligation. Lower elastin contents (38%) were also observed, although collagen contents were not affected. These changes were accompanied by a relative reduction in wall mass of 30% and a 31% reduction in internal diameter. Adult rabbits exhibited decreased internal diameter (21%) after flow reduction, but no significant change in vessel mass or wall constituents was observed. Early diameter reductions were vasoconstrictor in origin, but the vessel functioned as a smaller artery rather than as a partially constricted normal vessel after 1 mo, i.e., both maximally dilated and maximally constricted diameters were reduced. A reduction in endothelial cell number was detected for the narrowed vessels. Manipulation of local flow conditions indicated that the vessels responded to changes in mean blood flow rather than the pulsatile component of flow.
在通过结扎同侧颈外动脉使血流量减少70 - 80%后，对家兔颈总动脉的适应性反应进行了研究。这些血流量减少引发了未成熟家兔动脉壁组织的生长抑制。具体而言，在颈外动脉结扎1个月后，实验侧颈动脉的DNA水平显著低于对侧对照动脉，低35%。尽管胶原蛋白含量未受影响，但也观察到弹性蛋白含量较低（38%）。这些变化伴随着血管壁质量相对减少30%以及内径减少31%。成年家兔在血流量减少后内径减小（21%），但未观察到血管质量或壁成分有显著变化。早期内径减小源于血管收缩，但1个月后该血管作为一条较小的动脉发挥功能，而非部分收缩的正常血管，即最大扩张和最大收缩直径均减小。对于变窄的血管检测到内皮细胞数量减少。对局部血流状况的操控表明，血管对平均血流量的变化做出反应，而非对血流的脉动成分做出反应。
