Deletion of the insulin-like growth factor 1 (Igf1) gene was shown in previous studies to result in reduced numbers of Leydig cells in the testes of 35-day-old mice, and in reduced circulating testosterone levels. In the current study, we asked whether deletion of the Igf1 gene affects the number, proliferation, and/or steroidogenic function of some or all of the precursor cell types in the dev...

Testes of foetal pigs between 26 to 35 days post coitum (p.c.) were investigated histochemically and ultrastructurally. Diaphorase and delta 5-3 beta-hydroxysteroid dehydrogenase activities were studied using, respectively, NADH and pregnenolone and dihydroxy androsterone as substrates. Ultrastructurally, attention was focused on the development of mesenchymal cells and on the sustentacular cel...

The Leydigioma is a rare tumor of the testicle. It develops from the proliferation of the interstitial cells or Leydig cells, and compete with the endocrine activity of this organ.[1] It usually arises between 20 year and 50 year of life, and rarely reported in children.[2] International literature is rich about the management of testicular tumors in adults and often recommends radical orchidec...

Aromatization of testosterone in Leydig cells purified from mature rat testes was assessed. Leydig cells incubated for 4 hr with increasing concentrations of [3H]testosterone. At saturating concentrations of testosterone, human chorionic gonadotropin (hCG) acutely stimulated aromatization. This stimulation was first observed at 1 hr, an 8-fold increase being found during a 4-hr incubation. The ...

In humans, as in all mammalian males, Leydig cells are the main source of the androgenic hormone, testosterone, which is essential for male sexual differentiation, gamete production and maturation, and development of secondary sexual characteristics. In this chapter, the development, steroidogenic function, and regulation of human Leydig cells are summarized. Clinical aspects of androgen secret...

Ovarian sex cord-stromal tumors arise from the stromal cells that surround and support the oocytes. Sertoli-Leydig cell tumors belong to this category of ovarian neoplasms. We present the case of a 38-year-old woman who was found to have a right ovarian mass. The mass was resected and diagnosed as Stage I Sertoli-Leydig cell tumor, retiform variant, following histopathologic and immunohistochem...

The influence of prolactin (PRL) and corticosterone on insulin binding to purified rat Leydig cells was assessed in vitro. The lowest dose of PRL (50 ng/ml) increased (p<0.05) and the remaining PRL concentrations (100, 150, 200, 250 ng/ml) decreased (p<0.05) the insulin binding to Leydig cells. All doses of corticosterone (150, 200, 250, 300 ng/ml) except the lowest one (100 ng/ml) decreased th...

Disruption of normal fetal development can influence functioning of organs and cells in adulthood. Circumstantial evidence suggests that subtle reductions in fetal androgen production may be the cause of adult male reproductive disorders due to reduced testosterone production. The mechanisms through which these fetal events affect adult testosterone levels are largely unknown. A recent paper of...

background: diazinon (dzn) is an organophosphate insecticide which is used worldwide in agriculture. the exposure to this chemical might lead to damages to the living systems. objective: the present study was done to investigate the effects of diazinon on the structure of testis and levels of sex hormones in adult male mice. materials and methods: for this experiment, the mature male mice divid...

background: leydig cell tumor is a rare form of testicular neoplasm which comprises 1-3% of all testicular tumors and only about 3% of these tumors are bilateral. a few leydig all tumor have been described in patients with klinefelter�s syndrome so far. case: the patient described in this case report was a 24 year-old man with chief complaint of infertility for one year. physical examination, s...