Pawlik W W, Gustaw P, Czarnobilski K, Sendur R, Konturek S J
Institute of Physiology, School of Medicine, Cracow.
Acta Physiol Pol. 1987 Sep-Oct;38(5):410-7.
The effects of intra-arterial administration of substance P upon intestinal blood flow, oxygen consumption, intestinal motor activity, and distribution of blood flow to the compartments of the gut wall were measured in anesthetized dogs. Blood flow to the segment of distal ileum was measured with an electromagnetic blood flow meter and A-VO2 was measured spectrophotometrically. Oxygen uptake was calculated as the product of A-VO2 and total blood flow. The clearance of 86Rb was measured to estimate the density of the perfused intestinal capillaries. Changes in blood flow distribution were estimated from the distribution of radiolabeled microspheres. Motor activity was monitored from changes in intraluminal pressure. Substance P induced a dose-related increase in intestinal blood flow, oxygen consumption, and intestinal motor activity. A significant increase in 86Rb clearance and increase in blood flow to the muscles was also observed. The results of these studies indicate that substance P relaxes intestinal arterioles and precapillary sphincters thereby inducing intestinal hyperemia and increased oxygen consumption. These changes, at least in part, might be due to the increased intestinal motility with enhanced metabolic demands of the muscularis for oxygen.
在麻醉犬身上测量了动脉内注射P物质对肠血流量、氧耗量、肠运动活性以及肠壁各部分血流分布的影响。用电磁血流计测量回肠远端节段的血流量，用分光光度法测量动静脉氧含量差。氧摄取量通过动静脉氧含量差与总血流量的乘积计算得出。测量86Rb的清除率以估计灌注肠毛细血管的密度。根据放射性标记微球的分布估计血流分布的变化。通过腔内压力的变化监测运动活性。P物质引起肠血流量、氧耗量和肠运动活性呈剂量相关增加。还观察到86Rb清除率显著增加以及肌肉血流量增加。这些研究结果表明，P物质使肠小动脉和毛细血管前括约肌舒张，从而引起肠充血和氧耗量增加。这些变化至少部分可能是由于肠运动增加，肌层对氧的代谢需求增强所致。
