Role of GABA A receptors of the dorsomedial periaqueductal grey on blood pressure and heart rate in the anesthetized rat.

Autor: Baktashian Esfahani MH; Department of Physiology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran., Sherkat S; Department of Physiology, School of Medicine, Sabzevar University of Medical Sciences, Sabzevar, Iran., Shafei MN; Division of Neurocognitive Sciences, Psychiatry and Behavioral Sciences Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.; Applied Biomedical Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.
Jazyk: angličtina
Zdroj: Basic & clinical pharmacology & toxicology [Basic Clin Pharmacol Toxicol] 2024 Oct; Vol. 135 (4), pp. 441-450. Date of Electronic Publication: 2024 Sep 01.
DOI: 10.1111/bcpt.14070
Abstrakt: The midbrain dorsomedial periaqueductal grey column (dmPAG) is involved in the regulation of cardiovascular responses. Due to the presence of Gamma-Aminobutyric acid (GABA) receptors in the dmPAG, this study aimed to investigate the role of GABA A receptors in the dmPAG on cardiovascular parameters and its possible peripheral mechanisms. The left femoral artery was cannulated, and systolic arterial pressure (SAP), mean arterial pressure (MAP) and heart rate (HR) were recorded using a Power lab system. Microinjection of saline, muscimol and bicuculline (BIC) was done using a stereotaxic device. Also, the peripheral mechanisms dependent on GABA A receptors in the dmPAG were evaluated by intravenous (i.v.) injection of hexamethonium (Hexa) and atropine (Atr) 5 min before the BIC. Results showed that BIC significantly increased ∆SAP, ∆MAP and ∆HR than the control group, but muscimol had no significant effect. Injection of Hex significantly attenuates the effect of BIC on ∆SAP and ∆MAP. Atr (i.v) significantly increased the ∆HR, and when injected before BIC microinjection, it did not affect the cardiovascular responses induced by BIC. These findings show that GABA A receptors of the dmPAG have inhibitory effects on the cardiovascular system, which are mostly mediated by the sympathetic system.
(© 2024 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society). Published by John Wiley & Sons Ltd.)
Databáze: MEDLINE