Hall M E, Miley F B, Stewart J M
Life Sci. 1987 May 11;40(19):1909-14. doi: 10.1016/0024-3205(87)90050-6.
Considerable evidence suggests that substance P (SP) may be a transmitter mediating the depressor effects of baroreceptor reflex activation within the brainstem, yet intracerebroventricular administration of SP is reported to result in a pronounced pressor effect. In this study, SP injected into the 4th cerebral ventricle produced a biphasic effect; a brief decrease in blood pressure followed by a lengthy increase. Similar injections of a carboxy-terminal fragment of SP produced only a pressor effect of long duration. Injection of an amino-terminal SP fragment produced only a brief, rapid depressor effect. These results suggest that the amino-terminal sequence of SP may be involved in mediating the depressor effects of baroreceptor activation.
大量证据表明，P物质（SP）可能是一种递质，介导脑干内压力感受器反射激活的降压作用，然而据报道，脑室内注射SP会产生明显的升压作用。在本研究中，注入第四脑室的SP产生了双相效应；血压短暂下降，随后长时间升高。类似地注射SP的羧基末端片段仅产生长时间的升压作用。注射SP的氨基末端片段仅产生短暂、快速的降压作用。这些结果表明，SP的氨基末端序列可能参与介导压力感受器激活的降压作用。
