Transient activation of C-MYC protooncogene expression in leydig cells by human chorionic gonadotropin

Localization of receptor-bound human chorionic gonadotropin (hCG) in rat testis was studied by the peroxidase-antiperoxidase (PAP) complex method. The rats were injected with a single intravenous dose (1000 IU) of hCG. Three, 6, 12, and 24 hr after injection the testes were removed for localization of the hormone. The hormone localized to the periphery of the Leydig cells at all observation points. The intensity of the staining varied between the cells, suggesting that the number of receptors or the accessibility of the receptors to the circulating hormone varies from one cell to another. The staining surrounded the Leydig cells unevenly, but no progressive patching or capping was found. This observation suggests that hCG binds preferentially to the cell surface areas directed toward the capillaries. Compatible results were obtained with anti-hCG serum and with antisera against the hCG subunits. These results are consistent with previous observations that the luteinizing hormone (hCG) receptors accessible to the circulating hormone are located at the surface of the Leydig cells.

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In Vivo Pretreatment with Human Chorionic Gonadotropin Fails to Reverse the Dysfunction of Isolated Leydig Cells from Chronically Uremic Rats1

Biology of Reproduction ◽

10.1095/biolreprod33.4.781 ◽

1985 ◽

Vol 33 (4) ◽

pp. 781-789 ◽

Cited By ~ 4

Author(s):

P. D. Tsitouras ◽

M. A. Kowatch ◽

G. R. Briefel ◽

J. H. Kalbfleisch ◽

S. M. Harman ◽

...

Keyword(s):

Chorionic Gonadotropin ◽

Human Chorionic Gonadotropin ◽

Leydig Cells

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Cyp11b1 Is Induced in the Murine Gonad by Luteinizing Hormone/Human Chorionic Gonadotropin and Involved in the Production of 11-Ketotestosterone, a Major Fish Androgen: Conservation and Evolution of the Androgen Metabolic Pathway

Endocrinology ◽

10.1210/en.2007-1015 ◽

2007 ◽

Vol 149 (4) ◽

pp. 1786-1792 ◽

Cited By ~ 49

Author(s):

Takashi Yazawa ◽

Miki Uesaka ◽

Yoshihiko Inaoka ◽

Tetsuya Mizutani ◽

Toshio Sekiguchi ◽

...

Keyword(s):

Chorionic Gonadotropin ◽

Human Chorionic Gonadotropin ◽

Metabolic Pathway ◽

Leydig Cells ◽

Plasma Concentrations ◽

Luciferase Reporter ◽

Reporter System ◽

Mouse Ovary ◽

Luciferase Reporter System

We have shown previously that Cyp11b1, an 11β-hydroxylase responsible for glucocorticoid biosynthesis in the adrenal gland, was induced by cAMP in androgen-producing Leydig-like cells derived from mesenchymal stem cells. We found that Cyp11b1 was induced in male Leydig cells, or female theca cells, when human chorionic gonadotropin was administered in immature mice. Expression of Cyp11b1 in rodent gonads caused the production of 11-ketotestosterone (11-KT), a major fish androgen, which induces male differentiation or spermatogenesis in fish. As in teleosts, plasma concentrations of 11-KT were elevated in human chorionic gonadotropin-treated mice. In contrast to teleosts, however, plasma concentrations of 11-KT were similar in both sexes, despite levels of testosterone, a precursor substrate, being about 20 times higher in male mice. Because expression of 11β-hydroxysteroid dehydrogenase type 2, was much higher in the mouse ovary than in the testis, conversion of testosterone into 11-KT may occur more efficiently in the ovary. In a luciferase reporter system that was responsive to and activated by androgens, 11-KT efficiently activated mammalian androgen receptor-mediated transactivation. Our results suggest that the androgen metabolic pathway is conserved between teleosts and mammals, despite sexual dominance and reproductive functions of 11-KT being altered during evolution.

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