Views: 109 Downloads: 29

Abstract

This study aimed to evaluate brain serotonin turnover and its impact on heart rate variability during stress. Six groups of Sprague-Dawley mice received oral treatment for fifteen days. On the 7^th day, after the respective treatments, mice were first subjected to restraint stress for 30 min in Decapicone to induce acute stress, and then antidepressant action was assessed by the forced swim test (FST). On the 14^th day, ECG was also recorded in anesthetized mice using micro-hook electrodes (AD instrument, PowerLab), and heart rate (HR: beats per minute) and heart rate variability (HRV) were calculated. At the end of the study, brain serotonin (5HT), 5-hydroxyindole acetic acid (5HIAA), and serotonin turnover rate were measured by using a high-performance liquid chromatographic (HPLC) method.

Stress Control (SC) mice showed an increased serotonin (5HT; P<0.05) turnover rate and thus displayed significant anxiogenic behavior after experiencing acute restraint stress for 30 mins. Meanwhile, a significant dose-dependent reduction in 5HT (P<0.05) turnover rate, along with anxiolytic activity, was observed in mice (G3-6) pretreated with imipramine and different doses of ATEL (p < 0.05), respectively. Additionally, heart rate (HR) and HRV revealed an improvement in imipramine- and ATEL-treated stressed mice. Pre-treatment with ATEL enhances neurochemical (5-HT) availability and decreases its turnover rate, resulting in antidepressant effects and a reduction in stress-induced tachycardia, along with improved HRV. Therefore, ATEL appears to be a beneficial plant extract that could be useful for patients experiencing acute stress-induced tachycardia and depression.‎

Keywords: Acacia tortilis leaves ethanolic extract (ATEL), Heart rate variability (HRV), Anxiolytic activity, DMT, Serotonin (5HT)

Citation Formats: