Gonadotropin binding and stimulation of steroidogenesis in Leydig tumor cells
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چکیده
منابع مشابه
Gonadotropin binding and stimulation of steroidogenesis in Leydig tumor cells.
Testicular tumors are generally characterized by a loss of responsiveness to gonadotropins. The M5480 Leydig cell tumor is unusual, if not unique, in that it responds to human choriogonadotropin and to lutropin via increased steroidogenesis. This report describes the identification of two variants of the original M5480 tumor that have altered steroid output both in the basal state and in respon...
متن کاملCatecholamine stimulation of steroidogenesis in Leydig cells.
Although p-adrenergic control of another steroidogenic tissue, the ovary, has been established (Godkin et al., 1977; Jordan et al, 1978; Hunzicker-Dunn, 1980; Hunzicker-Dunn et al., 1979; Kliachko & Zor, 1981), there have been no reports that catecholamines can directly stimulate steroidogenesis in Leydig cells. During the course of our investigations on factors controlling Leydig activity in c...
متن کاملDesensitization to gonadotropins in cultured Leydig tumor cells involves loss of gonadotropin receptors and decreased capacity for steroidogenesis.
The ability of human choriogonadotropin (hCG) to regulate its receptors and target cell responses has been studied in a clonal strain of cultured Leydig tumor cells (MA-10). Exposure of the MA-10 cells to hCG results in decrease in hCG binding activity which is dependent on time and the concentration of hCG. This decrease is due to a change in the number of receptors rather than in the affinity...
متن کاملAqueous Extract of Nigella sativa Seeds Suppresses Testicular Steroidogenesis In Mice Leydig Cells, in vitro
Nigella sativa (black seed) is an important medicinal herb with folkloric use in wide range of diseases. It is well studied for its biological activities. However, there is limited information regarding its effect on the male reproductive system. This study describes the effect of the aqueous extract of N. sativa (NSE) on testicular steroidogenesis from mice Leydig cells in vitro . Mice tes...
متن کاملEstradiol receptor-mediated regulation of steroidogenesis in gonadotropin-desensitized Leydig cells.
The steroidogenic lesion produced in Leydig cells by gonadotropin stimulation has been attributed to an inhibitory effect of estrogen on 17a-hydroxylase and 17,20-desmolase activity, with impaired conversion of progesterone to androgens. In animals treated with doses of human chorionic gonadotropin (hCG) or gonadotropin-releasing hormone (GnRH) that caused the decrease in desmolase activity, ad...
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ژورنال
عنوان ژورنال: Proceedings of the National Academy of Sciences
سال: 1978
ISSN: 0027-8424,1091-6490
DOI: 10.1073/pnas.75.1.99