P物质对工作状态下大鼠心脏的作用。

Action of substance P on the working rat heart.

作者信息

Kulakowski E C, Lampson W G, Schaffer S W, Lovenberg W

出版信息

Biochem Pharmacol. 1983 Mar 15;32(6):1097-100. doi: 10.1016/0006-2952(83)90631-7.

Abstract

The effect of substance P (SP) on the cardiodynamics of the isolated working rat heart perparation was examined. The peptide over the concentration range of 10(-8) to 10(-6) M was found to have no influence on aortic pressure, cardiac output, or cardiac work. However, a 10-15% reduction in coronary flow was observed at 1 x 10(-6) M substance P. Octapeptide substance P (SP4-11) exhibited a similar vasoconstrictive action. The IC50 of SP4-11 was 2 x 10(-13) M compared to an IC50 of 3.5 x 10(-8) M for substance P. Perfusion of the heart in the presence of bacitracin (1 x 10(-4) M), a protease inhibitor, prevented the reduction in coronary flow observed in the presence of substance P. By contrast, the reduction in coronary flow produced by octapeptide substance P was not altered by the presence of bacitracin. Thus, it appears that a C-terminal fragment such as SP4-11 may be responsible for the observed decrease in coronary flow.

摘要

研究了P物质（SP）对离体工作大鼠心脏标本心脏动力学的影响。发现浓度范围在10^(-8)至10^(-6) M的该肽对主动脉压力、心输出量或心脏功没有影响。然而，在1×10^(-6) M P物质时观察到冠状动脉血流量减少了10 - 15%。八肽P物质（SP4 - 11）表现出类似的血管收缩作用。SP4 - 11的半数抑制浓度（IC50）为2×10^(-13) M，而P物质的IC50为3.5×10^(-8) M。在存在蛋白酶抑制剂杆菌肽（1×10^(-4) M）的情况下对心脏进行灌注，可防止在P物质存在时观察到的冠状动脉血流量减少。相比之下，八肽P物质引起的冠状动脉血流量减少不受杆菌肽存在的影响。因此，似乎C末端片段如SP4 - 11可能是观察到的冠状动脉血流量减少的原因。