title: Microinjection of acetylcholine into cerebellar fastigial nucleus induces blood depressor response in anesthetized rats.
abstract: 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.
authors.affiliation: School of Psychology, Nanjing Normal University, Nanjing, Jiangsu 210097, China; School of Life Sciences, Anqing Normal University, Anqing, Anhui 246133, China. Electronic address: neurobiologyzhang@yahoo.com.
authors.forename: Changzheng
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Department of Stomatology, The Affiliated Hospital of Hainan Medical University, Haikou, Hainan 570102, China.
authors.forename: Wen
authors.initials: W
authors.lastname: Luo
authors.affiliation: School of Life Sciences, Anhui Normal University, Wuhu, Anhui 241000, China.
authors.forename: Peiling
authors.initials: P
authors.lastname: Zhou
authors.affiliation: School of Life Sciences, Anqing Normal University, Anqing, Anhui 246133, China. Electronic address: confucian007@126.com.
authors.forename: Tingzhe
authors.initials: T
authors.lastname: Sun
mesh_terms: D000109:Acetylcholine / Q000008:administration & dosage*; D018686:Anesthetics, Intravenous / Q000008:administration & dosage; D000818:Animals; D001285:Atropine / Q000008:administration & dosage; D001794:Blood Pressure / Q000187:drug effects*; D002529:Cerebellar Nuclei / Q000187:drug effects* / Q000502:physiology*; D004305:Dose-Response Relationship, Drug; D008297:Male; D008464:Mecamylamine / Q000008:administration & dosage; D008845:Microinjections; D018727:Muscarinic Antagonists / Q000008:administration & dosage; D009538:Nicotine / Q000008:administration & dosage; D018733:Nicotinic Antagonists / Q000008:administration & dosage; D051381:Rats; D017207:Rats, Sprague-Dawley; D011976:Receptors, Muscarinic / Q000502:physiology*; D011978:Receptors, Nicotinic / Q000502:physiology; D014520:Urethane / Q000008:administration & dosage
chemical_list: D018686:Anesthetics, Intravenous; D018727:Muscarinic Antagonists; D018733:Nicotinic Antagonists; D011976:Receptors, Muscarinic; D011978:Receptors, Nicotinic; D014520:Urethane; D008464:Mecamylamine; D009538:Nicotine; D001285:Atropine; D000109:Acetylcholine
keywords: Acetylcholine; Blood pressure; Fastigial nucleus; Muscarinic acetylcholine receptor; Nicotinic acetylcholine receptor