The Reproductive System

Abstract

Correct sexual development is arguably the most important trait in an organism's life history since it is directly related to its genetic fitness. The developing gonad houses the germ cells, the only legacy we pass on to subsequent generations. Given the pivotal importance of correct reproductive function, it is confounding that disorders of sex development (DSDs) are among the most common congenital abnormalities in humans (Lee et al. J Pediatr Urol 8(6):611-615, 2012). Urogenital development is a highly complex process involving coordinated interactions between molecular and hormonal pathways in a tightly regulated order. The controls that regulate some of the key events in this process are beginning to be unraveled. This chapter provides an overview of our understanding of urogenital development from the gonads to the urogenital ducts and external genitalia.

Di‐(2‐ethylhexyl) phthalate (DEHP)‐induced testicular toxicity through Nrf2‐mediated Notch1 signaling pathway in Sprague–Dawley rats

“…Normal testicular development is considered an important prerequisite for maintaining normal reproductive function and sexual characteristics in males. 9,10 We previously found that exposure to DEHP after birth can cause testicular developmental abnormalities in Sprague-Dawley (SD) rats. One potential mechanism explaining the actions of DEHP involves oxidative stress.…”

Developmental programming and ageing of male reproductive function

“…1 Sertoli cells play an important role during testicular development, since their functions are necessary for the proper differentiation of germ cells, peritubular myoid cells and Leydig cells. 2 Leydig cells produce the testosterone 3 required for elongation of the seminiferous cords, masculinization of the reproductive tract and induction of testicular descent. 4 In humans, foetal rat testicular testosterone is detectable at 15.5 days This review will discuss effects of foetal exposure to maternal environmental challenges on male offspring fertility and normal ageing of the male reproductive system.…”

Novas perspectivas no diagnóstico etiológico dos distúrbios do desenvolvimento sexual 46, XY

“…A fase da determinação sexual se refere aos processos envolvidos no desenvolvimento do sexo gonadal, ou seja, dos eventos que culminam com a transformação da crista urogenital, que é tecido embriológico indiferenciado, para o estado de gônada bipotencial e subsequente diferenciação em gônada feminina ou masculina (3) .…”

“…A etapa da diferenciação sexual engloba os processos do desenvolvimento da genitália interna e externa que resultam no fenótipo feminino ou masculino (3) .…”

“…Este processo é dependente da ação dos hormônios secretados pelos testículos (3) . (3) . A testosterona, secretada pelas células de Leydig nos testículos fetais, age nos dutos de Wolff levando à formação das estruturas do sistema reprodutor masculino (7) .…”