Nitric oxide (NO) has emerged as an intracellular and intercellular messenger in a number of biological systems. In the present study, we demonstrated that NO was produced by cultured rat Leydig cells, and that inducible nitric oxide synthase (iNOS) messenger RNA (mRNA) was expressed in Leydig cells. NO was measured as nitrite with the method of Griess. Although unstimulated Leydig cells produc...

Sertoli-Leydig tumors tend to relapse early and due to their rarity, limited data are available regarding a role of chemotherapy in the management of Sertoli-Leydig cell tumors. We present a case of recurrent ovarian Sertoli-Leydig cell tumor whose salvage treatment was successful with paclitaxel and carboplatin chemotherapy.

Leydig cells are a target for their own steroid product, testosterone, and thus could be subject to short-loop feedback regulation by androgens. The authors previously reported that 3 beta-hydroxysteroid dehydrogenase-isomerase (3 beta HSD) activity was higher in freshly isolated Leydig cells from C57BL/6J than those from C3H/HeJ inbred mice. To determine whether this strain-related difference ...

Cultured Leydig cells exhibited time-dependent decreases in the microsomal cytochrome P-450 enzyme activities, 17 alpha-hydroxylase and C17-20 lyase when maintained under standard culture conditions (95% air, 5% CO2). Inclusion of the hydroxyl radical scavenger dimethyl sulfoxide in the culture medium, or the reduction of oxygen tension from 19 to 1% O2 was effective in preserving these enzyme ...

The influence of CRF on testosterone production in primary mouse Leydig cell cultures was studied, and the type of CRF receptor (CRF-R) involved in this activity was determined. CRF directly stimulated testosterone production in mouse Leydig cells, but did not influence the maximum human (h)CG-induced testosterone production. The effect was time- and dose-dependent, saturable with an EC50 of 2....

The development of estrogen-induced Leydig cell tumors in cryptorchid BALB/c mice was studied with the electron microscope. Changes in Leydig cell fine structure are apparent by 10 days after the s.c. implantation of a pellet of diethylstibestrol (DES). The smooth endoplasmic reticulum is diminished, and there is an increase in lipid droplets and free polysomes as compared with untreated crypto...

The aim of this study was to examine morphometric data of Leydig cells of 10 male chinchillas. Testes, cut into 5-microm thick sections, were stained using the p.a.S. and Masson's methods. Some 3800 Leydig cells have been evaluated. Their dimensions, as well as the diameters of their nuclei and the distances of the nuclei from the boundaries of the cells, have been measured. The areas of the su...

Aldosterone (ALDO) is a primary endogenous mineralocorticoid, appearing as the main hormone controlling sodium and water homeostasis. Its emerging role in the development of many organs has gained interest over the past few years. In the testis, Leydig cells contain mineralocorticoid receptors and ALDO stimulates androgen synthesis via the mineralocorticoid receptors in rat adult Leydig cells. ...

Advances in two techniques have made the problem of assessing the acute and/or chronic effects of toxic agents on Leydig cell structure and testosterone synthesis and secretion amenable to study. First, in vitro testicular perfusion has been perfected to a point where it closely resembles in situ testosterone secretion. Second, now it is possible to quantify the proportion of Leydig cell cytopl...

Testicular Leydig cells, which are the predominant source of the male sex steroid hormone testosterone, express estrogen receptors (ESRs) and are subject to regulation by estrogen. Following ingestion, the two major isoflavones in soybeans, genistin and daidzin, are hydrolyzed by gut microflora to form genistein and daidzein, which have the capacity to bind ESRs and affect gene expression. Thus...