Measurement of Hemodynamic Parameters and Antidepressant Activity in Hypertensive Rats Following Two Weeks Consumption of Acacia Tortilis Leaves Extract

Abstract

Background: Depression is common in hypertensive patients, and monotherapy may contribute to controlling depression in hypertensive patients and improving socioeconomic outcomes. Previous studies have shown that Acacia tortilis possesses hypotensive activity. Objectives: The present study was planned to evaluate the hemodynamic activity and antidepressant effects of an ethanolic extract of Acacia tortilis leaves (ATEL) in salt-induced hypertensive rats. Methods: Sprague-Dawley rats were divided into 5 groups for experiments. The rats received respective treatment for 15 days: G1: Control (C); G2: hypertensive control (HC: high dietary salt, 4% 10ml/kg); G3-5: HC+ ATEL (50, 100, 150mg/kg respectively). Cardiac hemodynamics (mean arterial blood pressure: MAP and heart rate: HR) were measured in the anaesthetized rats by an invasive method. For this method, one carotid artery was catheterized, a pressure catheter (pressure- volume Millar microtip catheter connected to the Mikro-Tip Pressure-Volume System from Ultra Foundation Systems, PowerLab) was inserted, and the blood pressure (MAP in mm Hg) and HR (beats/min) were monitored continuously during the experiment. For the neuropharmacological studies, antidepressant activity was assessed by a forced swim test on the 15th day. Results: A dose-dependent significant increase in mobility time was observed in rats (G3-5) treated with HC + different doses of ATEL (p < 0.05). However, the mobility time was significantly reduced by HC (G2) treatment compared to the control (p< 0.05). The hypertensive control (high dietary salt: HC) group showed a significant increase in systolic blood pressure (SP), diastolic blood pressure (DP), MAP and HR (p<0.05) compared to the control (G1) group. At all doses (50, 100, and 150 mg/kg), MAP and HR were found to decrease significantly (p<0.05) compared to the values in the HC (G2) group. Further analysis revealed an improvement in heart rate variability (HRV) in ATEL-treated hypertensive rats. Conclusion: The present research suggests that increased dietary salt intake not only increases blood pressure significantly but also increases depression. ATEL contains some efficacious constituents, such as N, N-dimethyltryptamine (DMT: a 5-HT1A agonist), with predominant antidepressant and antihypertensive activity. Hence, ATEL appears to be a valuable plant extract that can be useful, at least as an adjunct, for therapy in patients who suffer from both depression and hypertension.