Systemic Effects of Water Extract of Tetrapleura tetraptera, a Nigerian Plant Molluscicide Used in Schistosomiasis Control

Abstract

The effects of an aqueous extract of Tetrapleura tetraptera have been investigated in cats, dogs, rabbits and rats. Pharmacological examination showed that it possesses little or no hypotensive effect in cats, dogs and rabbits, but significantly depressed the blood pressure of anaesthetized rats. It had little or no effect on the PQRST complex of rats and dogs, aortic/dP/dt, LVPmax and LV dP/dt, respiratory rate and tidal volume, but dose-dependently decreased the cardiac effort index of these experimental animals. In one cat however, a cumulative dose of 136 mg/kg inhibited the neuromuscular activity of the cat tibialis anterior muscle in vivo. The concentration which caused this blockade (IC₅₀ = 136 mg/kg in 4 h) is many times higher than the concentration required for molluscicidal activity in the laboratory and the field.