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.