The Effects of abnormal prolactin levels on semen parameters on male white rats.

Abstract

INTRODUCTION:High prolactin levels drastically inhibit sperm production and its quality. The role of high prolactin levels on the male reproductive system has not been completely elucidated and thus its exact role in male factor infertility remains unclear. Hence this study was carried out in order to establish its effects. OBJECTIVE:To determine the effects of prolactin levels on semen parameters of male white rats. METHODOLOGY: A case control study was carried out in the Animal house of the Faculty of Medicine, University of Ruhuna, Sri Lanka. Ethical consent was obtained from the Ethical review committee, Faculty of Medicine, University of Ruhuna. 10+/- 2 week old, 200+/-10 g weighted Wistar strain male white rats weregrouped as G1-G6, with 30 rats per group. They were maintained in separately labeled cages at room temperature of 28+/- degrees Celsius. Hyperprolactinemia was induced in G3, G4 and G5 by using oral largactil a daily dose of 10mg/kg in two divided doseson G3, and subcutaneousinjections of fluphenazine in adose of 0.42mg/kg and 0.84mg/kg on G4and G5 respectively given as single doze in the morning. Hypoprolactinaemia was induced in G2 by using oral bromocriptine in a daily dose of 4.65mg/kg in two divided doses. After 100 days PR Llevels were assayed together with a BSA assessment on each of the groups. Results were compared with corresponding control groups and with each of the groups. RESULTS: The difference between the experimentally obtained values and corrected values for the serum PRL concentrations in the G2 which was administered bromocriptine to induce hypoprolactinaemia was found to be highly significant with compared to the control group by student’s t-test. The difference between the experimentally obtained values and corrected values for the serum PRL concentrations in the G3, G4, G5 which was administered largactil, low dose fluphenazine, high dose fluphenazine respectively to induce hyperprolactinaemia was found to be highly significant with compared to the control group by student’s t-test. Mortality, morphology, cell counts per field and the concentration of sperms seems to affected by serum PRL levels. A correlation between different PRL levels and the semen parameters was evident as those with high PRL levels show more abnormal basic semen analytical parameters while those with a moderate rise of PRL levels and hypoprolactinaemic rats show better basic semen analytical parameters. CONCLUSIONS: The level of serum PRL in white male rats has an effect on semen parameters. The level of effect is proportionate to the level of serum PRL. It is clearly evident that mortality, morphology, cell counts per field and the concentration of sperms are affected by PRL. Thus abnormal PRL levels appear to exert an effect on the spermatogenetic cycle.