Effect of aqueous extracts of pausinystalia yohimbe trunk bark on castration-induced sexual impotence in male rats

Medicinal plants have occupied since ancestral times a place of choice in the treatment of many pathologies that affect man, following the example of sexual impotence. The aim of the present study was to investigate the effect of an aqueous extract of P. yohimbe trunk bark on castration-induced sexual impotence in male rats. The animals were castrated using the slightly modified Roubinian technique. Fifteen days after castration the animals were divided and treated as follows: one batch distilled water control (0.5ml/100g W.O.), one batch testosterone enanthate (0.2ml/kg subcutaneously), one batch yohimbine (10mg/kg) and three batches aqueous extract of P. yohimbe (100, 250 and 500 mg/kg W.O.). The animals were dosed for seven days. On the last day, each animal was mated with a female previously treated with 600 µg of 17 β-Oestradiol. The study parameters were sexual mounts, number of erections, number of ejaculations and latency time between two consecutive mounts. In other castrated animals, previously treated with testosterone enanthate (0.2 ml/kg subcutaneously), the aqueous extract of P. yohimbe (100, 250 and 500 mg/kg) was administered and the study parameters were observed as before. Analysis of the results shows that the aqueous extract of P. yohimbe bark (100, 250 and 500 mg/kg) alone and the two reference molecules activate the sexual parameters compared with distilled water (0.5 ml/100g). The same result was observed when the administration of the extract was followed by that of the reference molecules. P. yohimbe trunk bark contains phytoandrogens and acts by potentiating the action of natural testosterone. The extract is an important remedy for the treatment of sexual impotence.