Chronic Lead Exposure Impairment of Hypothalamic-Pituitary-Gonadal Axis in Adult Male Wistar Rats: Biochemical and Histomorphological Evidence

Abstract

Introduction: The upsurge in male infertility has been associated with impaired hypothalamic-pituitary-gonadal (HPG) axis. There is a dearth of conclusive empirical data as to the deleterious impacts of heavy metal intoxication on male reproductive functioning through the HPG axis. Objective: This study seeks to elucidate the possible effects of chronic lead exposure on HPG signalling activities via biochemical and histopathological assessment. Experimental Section/Material and Methods: Forty adult male Wistar rats were randomised into four experimental groups (n=10). Group A, the control group received standard feed and water ad libitume. In Groups B, C and D, animals were orally administered lead acetate at concentrations of 2.5% 3.0% and 3.5%, respectively, using a stock solution of 150mg/kg once daily for 35 days. After the treatment period, all animals were fasted overnight and euthanized by cervical dislocation. Blood levels of anterior pituitary hormones (FSH and LH) were analysed using standard methods. Statistical analyses was done on graph pad prism. Testicular tissue was processed routinely for histopathological analyses using different stains. Results: Hormonal assays showed no significant changes in follicle-stimulating hormone (FSH) and luteinizing hormone (LH) (p>0.05) levels across groups. However, histological examination revealed alterations in testicular architecture, including disrupted spermatogonia cell arrangement and reduced Sertoli cell numbers, indicative of adverse effects on spermatogenesis. Conclusion: Chronic lead exposure adversely affects testicular histomorphology in adult male Wistar rats, potentially impacting reproductive function. While hormonal levels remain relatively unaffected, alterations in testicular structure suggest a direct impact on gonadal functions at a cellular level.