We undertook this work to determine the effect of a total aqueous extract of Hibiscus sabdariffa (Malvaceae) on the intestinal muscle of the rabbit to determine its mechanism of action. So the intestinal muscle is isolated and put in physiological medium. The amplitude and the frequency of the contractions are recorded on paper. The total aqueous extract of Hibiscus sabdariffa (AEHS) increases the amplitude of the rhythmic contractions of rabbit duodenum in a dose-dependent manner. The contractile force in reference medium is 0.44 ± 0.108 g/f. Doses ranging from 4.10-4 mg / ml to 8.10- 2 mg / ml increases the amplitude of the contractions and basal tone (p <0.001). AEHS for successive doses of 2.10-4, 2.10-3 and 8.10-2 mg / ml increases the contractile force of 2.12 ± 0.247 g / f, 3.945 ± 0.162 g / f and 5.13 ± 0.290 g / f (p <0.001). These increases are respectively of 381, 796 and 1065 %. Atropine has no effect on the effects induced by AEHS. Adding AEHS in the physiological medium containing adrenaline, increases rhythmic contractions abolished by adrenaline. These effects are identical to those of the propranolol in medium containing adrenaline. In a physiological medium containing nifedipine, calcium chelator and a calcium-free medium, the muscle is completely relaxed. In this case the addition of AEHS in these environments has no effect. But when the calcium is present in the physiological medium as reference, AEHS gradually increases the amplitude and the basal tone of the intestinal smooth muscle. AEHS therefore contains substances acting as propranolol (beta-blocker). This drink increases the influx of calcium ions. These facts justify the use of traditional medicine in AEHS to treat constipation and also all research undertaken for its hypotensive and antihypertensive effects.
