Evaluation of the comparative effects of antihypertensive drugs: Methyldopa and Moringa oleifera leaves on the hypothalamic–pituitary–gonadal axis in male Wistar rat

Background: Antihypertensive drugs have been reported to induce reproductive toxicity, and hypothalamic–pituitary–gonadal axis (HPG) is responsible for the control of reproductive functions. Hence, there is a need to compare the effects of taken commonly used synthetic and natural antihypertensive drugs (Methyldopa and Moringa oleifera) on HPG-axis. Aim: This study was aimed to determine the hypothalamic–pituitary–gonadal responses to the administration of methyldopa and aqueous extract of Moringa oleifera leaves in male Wistar rats. Methodology: Twenty-five male adult Wistar rats weighed between 150 and 200 g were divided into five groups (A–E), with each group comprising fi ve rats. Group E was designated as the control group which received physiological saline while rats of Group A and B received 200 and 400 mg/kg body weight of M. oleifera, respectively. Rats of Group C and D received 500 and 1000 mg/kg body weight of methyldopa, respectively, for 30 days. Results: Andrological parameters (sperm count, sperm morphology, sperm motility, serum testosterone, follicle-stimulating hormone, and luteinizing hormone concentration) in Group B rats showed significant increase when compare with the methyldopa-treated group (C and D) and control group E rats. Group D rats showed slight abnormalities in sperm morphology and slight decrease in sperm motility when compare with the control group E. Histoarchitecture of the testes of Group A, B, and E rats showed normal seminiferous tubules with full maturation of the germinal cell layers and only Group B rats contained more spermatozoa in their lumen. Group C and D rats showed some of their seminiferous tubules with incomplete maturation of germinal cell layers with their lumens contained fat deposit with no spermatozoa. Conclusion: The aqueous extract of M. oleifera leaves as an antihypertensive drug showed high beneficiary effects on male fertility over methyldopa.