Faculty Research 1980 - 1989
Testicular LH receptors and circulating hormone levels in three mouse models for inherited diseases (Tfm/y, lit/lit and hyt/hyt).
Document Type
Article
Publication Date
1986
Keywords
Disease-Models-Animal, Dwarfism-Pituitary: me, FSH, Gonadotropins-Chorionic, Hormones, Hypothyroidism: me, LH, Male, Mice, Mice-Mutant-Strains: me, Prolactin, Receptors-LH: me, SUPPORT-U-S-GOVT-P-H-S, Testicular-Feminization, Testis: me, Testosterone
First Page
349
Last Page
358
JAX Source
Endocrinol-Exp-(Bratisl). 1986 Dec; 20(4):349-58.
Grant
HD20001, HD20033, AM17937
Abstract
In mice with testicular feminization (Tfm/y), the concentration of LH receptors (LH-R) in the testes was greatly elevated, when compared to their normal controls (Ta/y). The administration of hCG caused, 24 hours later, a much greater decrease in the number of testicular LH-R in Tfm/y than in Ta/y mice. However, whereas in Ta/y mice, the decrease in LH-R was accompanied by a greater than 20 fold increase in plasma testosterone (T) levels, the same dose of hCG failed to alter plasma T levels in Tfm/y mice. Tfm/y mice were also characterized by significantly elevated circulating LH, FSH and PRL levels. Administration of hCG decreased testicular LH-R concentration in little (lit/lit) mice, whereas it had no effect in hypothyroid (hyt/hyt) and normal mice. Treatment with hCG elevated plasma T levels in all animals, but this increase was smaller in lit/lit than in Lit/- mice, while being greater in hyt/hyt than in Hyt/- mice. The present results suggest that the Tfm locus in the mouse is involved in the regulation of testicular LH-R. The only effect of GH deficiency on the parameters studied is on hCG-stimulated testicular steroidogenesis. The lack of negative autoregulation of LH-R by hCG in hyt/hyt mice may indicate a more active testicular LH-R metabolism, perhaps as a consequence of the chronic elevation of plasma TSH levels.
Recommended Citation
Amador AG,
Parkening TA,
Beamer WG,
Bartke A,
Collins TJ.
Testicular LH receptors and circulating hormone levels in three mouse models for inherited diseases (Tfm/y, lit/lit and hyt/hyt). Endocrinol-Exp-(Bratisl). 1986 Dec; 20(4):349-58.