Bethanidine (sulfate)

Bethanidine sulfate is an orally active antihypertensive agent and adrenergic neuron blocker. Bethanidine sulfate exerts its antihypertensive effect by inhibiting the release of norepinephrine from sympathetic nerve terminals. Bethanidine sulfate exhibits anti-ventricular arrhythmic activity. Bethanidine sulfate can be used in research related to hypertension, ventricular tachycardia, and ventricular fibrillation^[1][2][3]. In Vitro:Bethanidine sulfate (1-3 μg/mL) abolishes the inhibitory effect of neural stimulation on the pendular movement of isolated rabbit ileum^[1].
Bethanidine sulfate (1-10 μg/mL) attenuates the neurostimulatory contractile response of isolated guinea pig vas deferens at a concentration of 1 μg/mL, and completely abolishes this response at 3 μg/mL^[1].
Bethanidine sulfate (3-300 μg/mL) inhibits the peristaltic reflex of isolated guinea pig ileum; it reduces cholinergic sensitivity at concentrations of 3 to 30 μg/mL, and decreases the sensitivity to acetylcholine and histamine by 10-fold at a concentration of 300 μg/mL^[1].
Bethanidine sulfate (100-300 μg/mL) inhibits serotonin-induced contraction of isolated rat uterus and adrenaline-induced contraction of isolated rabbit uterus^[1]. In Vivo:Bethanidine sulfate (0.1-100 mg/kg; i.v./s.c./p.o.) produces potent, long-lasting adrenergic neuronal blockade in cats, preferentially inhibiting low-frequency sympathetic nerve stimulation, and is accompanied by transient sympathomimetic effects and neuromuscular blockade at high doses^[1].
Bethanidine sulfate (0.3-100 mg/kg; intravenous/oral administration) induces dose-dependent pressor effects, adrenergic neuron blockade, and enhanced amine responses in dogs, and exhibits good tolerance to high oral doses^[1].
Bethanidine sulfate (10 mg/kg; subcutaneous injection) transiently slows gastrointestinal transit in fasted rats, and an accelerated transit rate is observed 4 h after administration^[1].
Bethanidine sulfate reduces motor activity in mice at high doses. When administered intravenously at 12.5 mg/kg, it prolongs pentobarbital-induced hypnotic duration, and exhibits route-dependent toxicity, with an LD₅₀ of 12 mg/kg for intravenous injection and 520 mg/kg for oral administration^[1].
Bethanidine sulfate (300 mg/kg) increases the ventricular fibrillation threshold by 150% in the hearts of normal dogs and by 327% in the hearts of infarcted dogs, with no acute toxicity observed even at doses as high as 300 mg/kg^[2].