Respostas morfofuncionais adaptativas das células de Sertoli e Leydig associadas à sazonalidade reprodutiva em Crotalus durissus (Linnaeus, 1758)

Abstract

The reproductive ability of sexually mature males is related to the capacity of the testes to produce a high number of viable sperm and an adequate concentration of androgens for the maturation of the reproductive organs and the behavior involved in this process as well. For such functions, Sertoli cells and Leydig cells directly orchestrate the respective processes. Despite the great diversity of snakes in Brazil and abroad, little is known about how these somatic cells respond to reproductive seasonality, especially on males from tropical regions. Therefore, the present study evaluated the morphofunctional changes of Leydig and Sertoli cells developed as a response of seasonal adaptation to the different phases of testicular activity (regression, recrudescence and complete spermatogenesis) in the rattlesnake. However, it was found that to achieve homeostasis in the face of seasonal changes, Crotalus durissus undergoes changes in the morphology and composition of Sertoli cell (SC) and Leydig cells (LC), as well as in their populations. During regression, the elimination of germ cells through enthosis was found, in addition to the known process of apoptosis. For rapid removal of germ cells during regression, they were digested by SC and their lipid products were stored in lipid bodies, to ensure the nutrition of the tubular compartment according to seasonal demand. LC also showed morphological and functional plasticity in face of seasonal demands, suggesting that testosterone is necessary both for the spermatogenic process and for the male reproductive behavior in snakes.