Anderson D R, Davis E B
Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami School of Medicine, Fla., USA.
Ophthalmologica. 1996;210(5):280-4. doi: 10.1159/000310726.
We undertook this study to determine if pericytes respond to carbon dioxide in a manner such that they could help control capillary blood flow and that their physiologic responses to pCO2 might be worthy of detailed study. Pericytes were isolated from bovine retinas and grown in cell culture. Changes in the contractile tone of the pericytes upon changing the ambient pCO2 were observed by noting changes in the wrinkling of an elastic silicone surface on which they were grown. An increase in pCO2 caused acidosis of the medium and relaxation of the pericytes in a reversible, concentration-dependent manner. These findings suggest that the regulation of blood flow to meet local metabolic needs does not reside entirely in the arterioles and precapillary sphincters, but at least in part in the capillary bed through the contractile properties of pericytes. The local pCO2 is one of several potential indicators of whether or not local blood flow is adequate for local tissue needs. The response to local conditions may modulate or be modulated by the effect of neurotransmitters and hormones on the local rate of blood flow.
我们开展这项研究是为了确定周细胞是否以能够帮助控制毛细血管血流的方式对二氧化碳作出反应，以及它们对二氧化碳分压（pCO2）的生理反应是否值得详细研究。从牛视网膜中分离出周细胞并在细胞培养中生长。通过观察周细胞生长的弹性硅胶表面皱纹的变化，来观察改变环境pCO2时周细胞收缩张力的变化。pCO2升高导致培养基酸中毒，并使周细胞以可逆的、浓度依赖性方式松弛。这些发现表明，为满足局部代谢需求而进行的血流调节并非完全存在于小动脉和毛细血管前括约肌中，而是至少部分通过周细胞的收缩特性存在于毛细血管床中。局部pCO2是局部血流是否足以满足局部组织需求的几个潜在指标之一。对局部状况的反应可能会调节或被神经递质和激素对局部血流速率的影响所调节。
