The regulation of testicular descent and the effects of cryptorchidism

Abstract

The first half of this review examines the boundary between endocrinology and embryonic development, with the aim of highlighting the way hormones and signaling systems regulate the complex morphological changes to enable the intra-abdominal fetal testes to reach the scrotum. The genitoinguinal ligament, or gubernaculum, first enlarges to hold the testis near the groin, and then it develops limb-bud-like properties and migrates across the pubic region to reach the scrotum. Recent advancesshowkey roles for insulin-likehormone3 inthe first step, with androgenandthe genitofemoral nerve involved in the second step.Themammarylinemayalsobeinvolved in initiating the migration. The key events in ear..