Evaluation of some pharmacological and histological profiles of the effect of an alcoholic extract of the dried roots of mondia whitei (periplocaceae) on albino rats, using projected doses based on the folkloric use of the plant
The alcoholic extract of the dried roots of M. whitei (reported to have aphrodisiac properties in local folklore) was evaluated for its pharmacological potential on the vas deferens of male rats and on the uterus of non-pregnant female albino rats. It was administered orally to the immature male rats to evaluate it androgenic or anti-androgenic activity in the testis and some accessory organs of the reproductive system. No acute toxic symptoms were observed after an oral administration of up to 1052.16 mg/kg of M. whitei extract. Sub-acute and chronic toxicity studies also revealed no damage to vital organs like the kidney and liver. Doses of ethanolic extract of M. whitei that were used were based on the prescribed folkloric intake of M. whitei dried roots. The dose required by an average 70 kg man was calculated and dose per body weight of each rat used extrapolated. Oral doses of 2.05, 4.11 and 8.22 mg/kg body weight administered for 3 weeks showed no androgenic or anti-androgenic effects with respect to the relative weights and histological profiles of sections of the testis, seminal vesicles, ventral prostate and epididymis. Increases in ventral prostate and epididymal weights of the extract-treated rats indicated no antiandrogenic activity. However, the reduction of the weight of the seminal vesicles after 7 days of treatment could indicate its inhibitory effect in this gland type and may be time dependent. However, a combination of 2.05 mg/kg M whitei and 1 mg/kg testosterone had a stimulatory effect on the weights of seminal vesicles and ventral prostate over the administration period of 21 days. There was also an increase in epididymal weight for this same dose level combination indicating possible androgenic activity of M whitei. M whitei administered at all dose levels was not anti-androgenic and therefore gave no indications of anti-fertility potential. Experiments on the isolated rat vas deferens and rat uterus preparations indicate that M whitei may have agonist activity on 3-adrenoceptors. A relaxation effect on the uterine smooth muscle occurred. It is safe to take M. whitei root extract even up to a dose of 1052.16 mg/kg with no visible toxic effect as well as causes no damage to the liver and kidneys at 8.22 mg/kg dose levels. M. whitei has no anti-androgenic effect on the male reproductive processes at the folkloric dose.
A thesis submitted to the Department of Biological Sciences, the School of Postgraduate Studies in partial fulfilment of the requirements for the degree of Master of Philosophy (Reproductive Biology), 2005