Influence of cimetidine and bromocriptine on prolactin levels in rat fertility

The present study was designed to see the effects of parenterally administered drugs cimetidine and bromocriptine affecting serum prolactin upon the fertility of adult male albino rats. Ninety adult young male albino rats between the ages of 60 to 120 days were selected. The animals were divided into three groups. Cimetidine was administered in a dose of 200 mg/kg body weight to group B intramuscularly and in addition to cimetidine, bromocriptine in a dose of 2.5 mg/day intramuscularly was given to group C. Normal saline was administered intramuscularly to control group A. Plasma prolactin was measured by Enzyme Immunoassays. Spermatogonia, spermatocytes, and spermatids were studied under oil immersion. The final plasma prolactin level instead of being elevated was found slightly depressed though insignificant in case of group B while remained slightly elevated instead of being suppressed/depressed though insignificant in group C. In group B spermatogenesis was normal in almost all of the tubules but a few of them were seen lined with only Sertoli cells and all the other germ cells like spermatogonia, primary spermatocytes, spermatids early and late, and spermatozoa were absent indicating total atrophy with both Sertoli cells and Leydig cells hyperplasia. While in the moderately affected tubules different types of spermatogonia A/B or intermediate were seen near the basement membrane. In group C both normal and abnormal germinal epithelium was seen in same/different tubules but a few of them were seen lined with only Sertoli cells and all the other germ cells like spermatogonia, primary spermatocytes, spermatids early and late, and spermatozoa were absent. The process of spermatogenesis was variable and appeared to be normal in most but in some it was found to be suppressed. This study revealed that the toxic effect of the drugs contributes to the infertility. It has not shown to be mediated through hormones in present study for which further research work is needed using low dose and longer duration to see the role of prolactin in causing infertility.