Autoregulatory Responses of Cat Mesenteric Arterioles Measured in Vivo
Autoregulatory Responses of Cat Mesenteric Arterioles Measured in Vivo
复制标题
体内测量的猫肠系膜小动脉的自动调节反应
作者：
P. Johnson
这些研究的目的是测量随着大动脉压力的变化，小动脉直径的变化。用飞点显微镜测量麻醉猫肠系膜血管直径的变化。动脉压在一个步骤中降低，并保持在恒定水平，直到直径的变化完成。在对34条小动脉的实验中，10条血管显示出随着压力降低而直径简单减小; 24条显示出双相反应。在后一组中，血管在最初的5至15秒内变窄，但在此之后发生了自动调节反应，血管扩张。其中12条血管的直径在低血压时比正常动脉压时变大。当压力突然恢复时，血管进一步扩张，但随着自动调节反应的发生而恢复到对照大小。分析的结果表明，稳定性的条件是满足在不同的部分的压力范围。
The purpose of these studies was to measure changes in the diameter of arterioles as large-artery pressure was varied. Changes in diameter were measured with a flying spot microscope in blood vessels of the mesentery of anesthetized cats. Arterial pressure was reduced in a single step and held at a constant level until the change in the diameter was complete. In experiments on 34 arterioles, 10 vessels showed a simple decrease in diameter as pressure was reduced; 24 showed a biphasic response. In the latter group the vessel narrowed for the first 5 to 15 seconds, but after this time an autoregulatory response occurred and the vessel dilated. In 12 of these vessels the diameter became larger in hypotension than it had been at normal arterial pressure. When pressure was suddenly restored, the vessel dilated further but returned to the control size as the autoregulatory response occurred. Analysis of the findings suggests that conditions of stability are satisfied in various portions of the pressure range.