Hibiscus Sabdariffa Calyx Research Articles

Testicular effects of sub-chronic administration of Hibiscus sabdariffa calyx aqueous extract in rats

The sub-chronic effect of Hibiscus sabdariffa (HS) calyx aqueous extract on the rat testes was investigated with a view to evaluate the pharmacological basis for the use of HS calyx extract as an aphrodisiac. Three test groups received different doses of 1.15, 2.30, and 4.60 g/kg based on the LD 50. The extracts were dissolved in the drinking water. The control group was given equivalent volume of water only. The animals were allowed free access to drinking solution during the 12-week period of exposure. At the expiration of the treatment period, animals were sacrificed, testes excised and weighed, and epididymal sperm number recorded. The testes were processed for histological examination. Results did not show any significant ( P>0.05) change in the absolute and relative testicular weights. There was, however, a significant ( P<0.05) decrease in the epididymal sperm counts in the 4.6 g/kg group, compared to the control. The 1.15 g/kg dose group showed distortion of tubules and a disruption of normal epithelial organization, while the 2.3 g/kg dose showed hyperplasia of testis with thickening of the basement membrane. The 4.6 g/kg dose group, on the other hand, showed disintegration of sperm cells. The results indicate that aqueous HS calyx extract induces testicular toxicity in rats.

Neuropharmacological Effects of Hibiscus sabdariffa Aqueous Extract

The neuropharmacological effects of the aqueous extract of Hibiscus sabdariffa (HS) calyx were studied in rodents. HS (100, 200 and 400 mg/kg, i.p.) caused a remarkable dose-dependent decrease in spontaneous motor activity in mice and increased the duration of pentobarbital (40 mg/kg, i.p.) induced sleep in rats. The extract (100-400 mg/kg, i.p.) significantly reduced the exploratory behaviour in mice. The extract significantly inhibited the intensity of apomorphine (1 mg/kg, s.c.) induced stereotypic behaviour and attenuated climbing in the mice dose-dependently. Similarly, chlorpromazine (3 mg/kg, i.p.) blocked apomorphine induced stereotype behaviour significantly. The intraperitoneal LD 50 of the extract was estimated to be greater than 5000 mg/kg. These results suggest that the aqueous extract of HS may contain psychoactive substances that are sedative in nature and which contribute to its use in traditional medicine as sedative.

Antihypertensive effect of roselle (Hibiscus sabdariffa) calyx infusion in spontaneously hypertensive rats and a comparison of its toxicity with that in Wistar rats

Antihypertensive effect of roselle (Hibiscus sabdariffa) calyx infusion in spontaneously hypertensive rats and a comparison of its toxicity with that in Wistar rats