Follicle-stimulating hormone-induced prostaglandin E formation in isolated rat ovarian theca

1983 ◽  
Vol 97 (1) ◽  
pp. 43-49 ◽  
Author(s):  
U. Zor ◽  
B. Strulovici ◽  
R. Braw ◽  
H. R. Lindner ◽  
A. Tsafriri

The aim of this study was to search for direct biochemical effects of highly purified FSH on isolated ovarian follicular theca in vitro. Granulosa cells (GC; approximately 1 × 105 cells per follicle) were flushed from isolated follicles of pro-oestrous rats. The remaining theca layer and the isolated GC were incubated with highly purified ovine FSH. Prostaglandin E (PGE) accumulation was measured by radioimmunoassay. Follicle-stimulating hormone induced a 15-fold increase in PGE accumulation over the basal level in the follicular theca, the stimulated rate exceeding threefold that observed in the GC fraction derived from the same follicle. Follicle-stimulating hormone caused no significant increase in cyclic AMP level or steroidogenesis in the theca layer, but was active on these parameters in the GC. In contrast, LH increased the accumulation of cyclic AMP, progesterone and testosterone, as well as of PGE, in follicular theca. Exogenous 8-bromo cyclic AMP or cyclic GMP also stimulated PGE production in follicular theca or GC, but FSH was without any effect on the level of endogenous cyclic GMP in GC or follicular theca. Antibodies to FSH prevented the effect of FSH (but not that of LH) on PGE formation by follicular theca and GC, while antibodies to the β-subunit of LH blocked the effect of LH but not of FSH. We conclude that highly purified FSH has a stimulatory effect on PGE formation by the follicular theca.

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.


1976 ◽  
Vol 68 (2) ◽  
pp. 283-287 ◽  
Author(s):  
BRIDGET I. BAKER

SUMMARY Various agents were tested for their ability to oppose the stimulatory effect of dibutyryl cyclic AMP on the release of the melanocyte-stimulating hormone from the rat neuro-intermediate lobe in vitro. Only dopamine exhibited an inhibitory effect; serotonin, γ-aminobutyric acid, tocinoic acid, tocinamide, the tripeptide Pro-Leu-Gly-NH2 and dibutyryl cyclic GMP were all ineffective.


1976 ◽  
Vol 70 (2) ◽  
pp. 285-291 ◽  
Author(s):  
G. L. RIGLER ◽  
G. T. PEAKE ◽  
A. RATNER

SUMMARY The role of prostaglandins in both FSH- and LH-mediated increases in ovarian cyclic AMP was examined in rats in vivo. Dose-related increases in ovarian cyclic AMP levels were observed 10 min after intravenous injection of FSH or LH. No changes in ovarian prostaglandin E (PGE) content were detected after injection of either gonadotrophin at doses which substantially enhanced cyclic AMP accumulation. Prior treatment of rats with indomethacin produced a greater than 50% decrease in ovarian PGE levels, but did not prevent the FSH- or LH-induced rise in ovarian cyclic AMP concentration. These in vivo experiments do not support the concept that PGE plays a role as an obligatory mediator for the gonadotrophin-induced rise in ovarian cyclic AMP levels.


1981 ◽  
Vol 90 (1) ◽  
pp. 89-96 ◽  
Author(s):  
BRIAN WEATHERHEAD ◽  
ANN LOGAN

In short-term (48 h) cultures of hair follicles α-melanocyte-stimulating hormone (α-MSH) and cyclic AMP stimulated melanogenesis through an increase in tyrosinase activity. In contrast cyclic GMP mimicked the effects of melatonin by inhibiting melanin production without causing a concomitant decrease in tyrosinase activity. Both cyclic GMP and melatonin blocked the stimulatory effects of cyclic AMP and α-MSH on melanin production but they left the increased levels of tyrosinase activity unaffected. Phosphodiesterase inhibitors (3-isobutyl-1-methylxanthine and papaverine) simultaneously stimulated tyrosinase activity and inhibited melanin production, presumably by allowing endogenous cyclic AMP and cyclic GMP to accumulate intracellularly. It is suggested that whereas MSH stimulates melanogenesis through a cyclic AMP-dependent mechanism there must also be an inhibitory cyclic GMP-dependent mechanism, perhaps activated by melatonin, which operates at some post-tyrosinase step in the melanin biosynthetic pathway.


2021 ◽  
Vol 22 (18) ◽  
pp. 10110
Author(s):  
Kaiana Recchia ◽  
Amanda Soares Jorge ◽  
Laís Vicari de Figueiredo Pessôa ◽  
Ramon Cesar Botigelli ◽  
Vanessa Cristiane Zugaib ◽  
...  

Follicle stimulating hormone (FSH) is produced by the pituitary gland in a coordinated hypothalamic–pituitary–gonadal (HPG) axis event, plays important roles in reproduction and germ cell development during different phases of reproductive development (fetal, neonatal, puberty, and adult life), and is consequently essential for fertility. FSH is a heterodimeric glycoprotein hormone of two dissociable subunits, α and β. The FSH β-subunit (FSHβ) function starts upon coupling to its specific receptor: follicle-stimulating hormone receptor (FSHR). FSHRs are localized mainly on the surface of target cells on the testis and ovary (granulosa and Sertoli cells) and have recently been found in testicular stem cells and extra-gonadal tissue. Several reproduction disorders are associated with absent or low FSH secretion, with mutation of the FSH β-subunit or the FSH receptor, and/or its signaling pathways. However, the influence of FSH on germ cells is still poorly understood; some studies have suggested that this hormone also plays a determinant role in the self-renewal of germinative cells and acts to increase undifferentiated spermatogonia proliferation. In addition, in vitro, together with other factors, it assists the process of differentiation of primordial germ cells (PGCLCs) into gametes (oocyte-like and SSCLCs). In this review, we describe relevant research on the influence of FSH on spermatogenesis and folliculogenesis, mainly in the germ cell of humans and other species. The possible roles of FSH in germ cell generation in vitro are also presented.


1983 ◽  
Vol 50 (04) ◽  
pp. 804-809 ◽  
Author(s):  
Torstein Lyberg

SummaryHuman monocytes in vitro respond to various agents (immune complexes, lectins, endotoxin, the divalent ionophore A 23187, 12-0-tetradecanoyl-phorbol 13-acetate [TPA], purified protein derivative [PPD] of Bacille Calmette-Guerin) with an increased synthesis of the protein component of thromboplastin. The effect of cyclic AMP and cyclic GMP on this response has been studied. Dibutyryl-cyclic AMP, prostaglandin E1 and the phosphodiesterase inhibitors 3-butyl-1-methyl-xanthine (MIX) and rac -4-(3-butoxy-4-methoxybenzyl)-2-imidazolidinone (Ro 201724), separately and in combination have a pronounced inhibitory effect on the response to immune complexes and PPD, and a moderate effect on the response to endotoxin and lectins. The effect on TPA response and on the response to A 23187 was slight. Dibutyryl-cyclic GMP (1 mM) gave a slight inhibition of the TPA arid IC response, but had essentially no effect on the response to other inducers. The intracellular cAMP level increased when monocytes were incubated with IC, TPA or A 23187 followed by a decrease to basal levels within 1-2 hr, whereas lectin (PHA) and PPD did not induce such changes. The cAMP response to endotoxin varied. Stimulation with IC induced an increase in monocyte cGMP levels, whereas the other stimulants did not cause such changes.


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