Li Peiwu, Fu Xu, Lu Yan, Yin Wen, Ma Li, Fu Zhongxue
aDepartment of General Surgery, First Affiliated Hospital, Chongqing Medical University, Chongqing bDepartment of Emergency, Lanzhou University Second Hospital cDepartment of Clinical Laboratory, San Aitang Hospital, Lanzhou, China.
Neuroreport. 2014 May 28;25(8):612-7. doi: 10.1097/WNR.0000000000000149.
Endothelin-1₁₋₃₁ (ET-1₁₋₃₁) is a 31-amino-acid vasoactive peptide that plays an important role in the regulation of cardiovascular function. However, the cardiovascular effects of central ET-1₁₋₃₁ are still not fully understood. In this study, we assess the effects of ET-1₁₋₃₁ within the nucleus tractus solitarius (NTS) of anesthetized rats and explore the underlying mechanisms of these effects. Bilateral microinjections of ET-1₁₋₃₁ into the NTS produced dose-dependent hypotension and bradycardia, very similar to the effects of a unilateral microinjection of ET-1₁₋₃₁ into the NTS. Bilateral microinjections of ET-1₁₋₃₁ into the NTS significantly decreased baroreflex function in a time-dependent manner. The hypotensive and bradycardic effects induced by the microinjection of ET-1₁₋₃₁ into the NTS were significantly decreased by the ETA receptor antagonist BQ123 and by kynurenic acid, but not by the ETB receptor antagonist BQ788. These results show that ET-1₁₋₃₁ injected into the NTS produces hypotension and bradycardia, mediated by ETA receptors and, at least partly, by the glutamate receptor.
内皮素-1₁₋₃₁（ET-1₁₋₃₁）是一种由31个氨基酸组成的血管活性肽，在心血管功能调节中发挥重要作用。然而，中枢ET-1₁₋₃₁对心血管的影响仍未完全明确。在本研究中，我们评估了ET-1₁₋₃₁对麻醉大鼠孤束核（NTS）的作用，并探讨其潜在机制。向NTS双侧微量注射ET-1₁₋₃₁可产生剂量依赖性的低血压和心动过缓，这与向NTS单侧微量注射ET-1₁₋₃₁的效果非常相似。向NTS双侧微量注射ET-1₁₋₃₁可随时间显著降低压力感受性反射功能。向NTS微量注射ET-1₁₋₃₁所诱导的低血压和心动过缓效应，可被ETA受体拮抗剂BQ123和犬尿氨酸显著减弱，但不被ETB受体拮抗剂BQ788减弱。这些结果表明，向NTS注射ET-1₁₋₃₁可产生低血压和心动过缓，其由ETA受体介导，且至少部分由谷氨酸受体介导。
