Zhang Changzheng, Luo Wen, Zhou Peiling, Sun Tingzhe
School of Psychology, Nanjing Normal University, Nanjing, Jiangsu 210097, China; School of Life Sciences, Anqing Normal University, Anqing, Anhui 246133, China.
Department of Stomatology, The Affiliated Hospital of Hainan Medical University, Haikou, Hainan 570102, China.
Neurosci Lett. 2016 Aug 26;629:79-84. doi: 10.1016/j.neulet.2016.06.063. Epub 2016 Jun 29.
It is well known that the cerebellar fastigial nucleus (FN) is involved in cardiovascular modulation, and has direct evidence of cholinergic activity; however, whether and how acetylcholine (ACh) in the FN modulates blood pressure has not been investigated. In this study, we analyzed mean arterial pressure, maximal change in mean arterial pressure, and the reaction time of blood pressure changes after microinjection of cholinergic reagents into the FN in anesthetized rats. The results showed that ACh evoked a concentration-dependent (10, 30 and 100mM) effect on blood pressure down-regulation. The muscarinic ACh (mACh) receptor antagonist atropine, but not the nicotinic ACh (nACh) receptor antagonist mecamylamine, blocked the ACh-mediated depressor response. The mACh receptor agonist oxotremorine M, rather than nACh receptor agonist nicotine, mimicked the ACh-mediated blood pressure decrease in a dose-dependent manner (10, 30 and 100mM). These results indicate that cholinergic input in the cerebellar FN exerts a depressor effect on systemic blood pressure regulation, and such effects are substantially contributed by mACh rather than nACh receptors, although the precise mechanism concerning the role of mACh receptor in FN-mediated blood pressure modulation remains to be elucidated.
众所周知，小脑顶核（FN）参与心血管调节，并且有胆碱能活动的直接证据；然而，FN中的乙酰胆碱（ACh）是否以及如何调节血压尚未得到研究。在本研究中，我们分析了在麻醉大鼠的FN中微量注射胆碱能试剂后平均动脉压、平均动脉压的最大变化以及血压变化的反应时间。结果表明，ACh对血压下调产生浓度依赖性（10、30和100mM）效应。毒蕈碱型ACh（mACh）受体拮抗剂阿托品可阻断ACh介导的降压反应，而烟碱型ACh（nACh）受体拮抗剂美加明则不能。mACh受体激动剂氧化震颤素M而非nACh受体激动剂尼古丁以剂量依赖性方式（10、30和100mM）模拟了ACh介导的血压下降。这些结果表明，小脑FN中的胆碱能输入对全身血压调节产生降压作用，并且这种作用主要由mACh而非nACh受体介导，尽管mACh受体在FN介导的血压调节中的精确机制仍有待阐明。
