REDUCTION OF HUMAN AND RAT TESTICULAR FOLLICLE STIMULATING HORMONE RECEPTORS BY HUMAN MENOPAUSAL GONADOTROPHIN IN VIVO AND IN VITRO

1987 ◽  
Vol 26 (6) ◽  
pp. 675-684 ◽  
Author(s):  
M. NAMIKI ◽  
M. NAKAMURA ◽  
A. OKUYAMA ◽  
T. SONODA ◽  
H. ITATANI ◽  
...  
1977 ◽  
Vol 74 (3) ◽  
pp. 441-447 ◽  
Author(s):  
PAUL LICHT ◽  
ANTONELLA BONA GALLO ◽  
ANNE STOCKELL HARTREE ◽  
RATNA C. SHOWNKEEN

SUMMARY The actions of human follicle-stimulating hormone (hFSH) and its β-subunit were examined in several assays in reptiles, including effects on lizard testicular activity (growth and androgen production) in vivo, and stimulation of androgen production by snake testes and competition for binding of 125I-labelled hFSH in lizards and snakes in vitro. Binding was also examined with mammalian tissues. The hFSH was highly steroidogenic in the snake and lizard; otherwise results were similar to those observed in mammals. In all cases, the potency of the β-subunit was only a few per cent of the intact hormone. The potency of hFSH in vivo compared with NIH-FSH ovine standards was several 100 times greater than in vitro. Results for stimulation of androgen production in vivo closely paralleled those for binding assays in both reptiles and mammals. In contrast to previous results for ovine FSH β-subunit, human FSH β-subunit has little if any FSH biological activity in reptiles.


Endocrinology ◽  
2009 ◽  
Vol 150 (10) ◽  
pp. 4784-4793 ◽  
Author(s):  
Yogeshwar Makanji ◽  
Peter D. Temple-Smith ◽  
Kelly L. Walton ◽  
Craig A. Harrison ◽  
David M. Robertson

1979 ◽  
Vol 82 (2) ◽  
pp. 253-262 ◽  
Author(s):  
M. R. SAIRAM

SUMMARY A modified bovine testicular receptor was used to evaluate highly purified follicle-stimulating hormone (FSH) from a number of species. The particulate receptor obtained from adult bovine testes could be stored frozen or lyophilized for long periods without appreciable decrease in the binding of the ligand facility or in loss of specificity. The bovine testis receptor binds twice as much 125I-labelled ovine FSH as 125I-labelled human hormone. When FSH from different species was compared against NIH-FSH-S10, using various FSH ligands, the ovine hormone was clearly the most active, although many had comparable in-vivo biological potencies. The results suggest that there is probably some species specificity in the hormone–receptor interactions. As the ovine hormone is structurally closer to the bovine, from which the receptor was derived, it appears to have the highest activity in vitro. Marked differences in the biological activities of the different preparations between the human chorionic gonadotrophin-augmentation test and the in-vitro assays have been observed. In the in-vitro assays, all preparations, with the exception of the porcine hormone preparation, were less active and the ratio of bioassay/radioreceptor assay varied widely. In the radioreceptor assays, all FSH preparations except pregnant mare serum gonadotrophin (PMSG) showed parallel inhibition curves. The three different PMSG preparations examined gave inhibition lines that were parallel to each other.


2008 ◽  
Vol 82 (5) ◽  
pp. 383-391 ◽  
Author(s):  
Veronique Ritter ◽  
Barbara Thuering ◽  
Pierre Saint Mezard ◽  
Ngoc-Hong Luong-Nguyen ◽  
Yves Seltenmeyer ◽  
...  

1977 ◽  
Vol 75 (1) ◽  
pp. 155-159 ◽  
Author(s):  
A. J. M. C. PICKERING ◽  
G. FINK

Pituitary incubation studies were carried out which showed that in the rat luteinizing hormone releasing factor (LH-RF) can exert a priming effect on FSH secretion in vitro. It was found that, as for LH, the effect depends on protein synthesis. The priming effect of LH-RF with respect to FSH could also be demonstrated in vivo; however, the effect was less dramatic than for LH.


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