REPTILIAN OVARIAN STEROIDOGENESIS AND THE INFLUENCE OF MAMMALIAN GONADOTROPHINS (FOLLICLE-STIMULATING HORMONE AND LUTEINIZING HORMONE) IN VITRO

1974 ◽  
Vol 62 (2) ◽  
pp. 267-275 ◽  
Author(s):  
S. W. C. CHAN ◽  
I. P. CALLARD
Keyword(s):  
Luteinizing Hormone ◽  
Ovarian Function ◽  
Cholesterol Metabolism ◽  
Ovarian Tissue ◽  
Follicle Stimulating Hormone ◽  
Sampling Period ◽  
Steroid Synthesis ◽  
Stimulating Hormone

SUMMARY The synthesis of steroids from [7α-3H]cholesterol, [7α-3H]pregnenolone and [7α-3H]progesterone by lizard and turtle ovarian tissues in vitro was studied. Progesterone, 17α-hydroxyprogesterone, dehydroepiandrosterone, androstenedione, testosterone, oestrone and oestradiol were identified as products. In the turtle (Pseudemys), conversion of pregnenolone to progesterone was efficient, but transformation of progesterone to other steroids was relatively slow as indicated by the accumulation of progesterone over the incubation period. In Dipsosaurus, accumulation of radioactivity was greatest in testosterone, the quantities of which continued to increase at each sampling period. The rate of utilization of pregnenolone as a substrate was similar for the two species studied and the quantities of oestrone and oestradiol formed were lower in Pseudemys. The use of progesterone as precursor by Dipsosaurus ovarian tissue revealed a similar pattern of Δ4-steroid metabolism to that obtained with pregnenolone as precursor. The effects of addition of purified follicle-stimulating hormone (FSH) and luteinizing hormone (LH) on the metabolism of [14C]cholesterol in vitro was studied using Pseudemys follicular tissue. The pattern of cholesterol metabolism was similar to that for pregnenolone in this species. The synthesis of pregnenolone, progesterone, dehydroepiandrosterone and androstenedione in vitro was significantly enhanced in the presence of LH. Follicle-stimulating hormone had no effect on steroid synthesis except for a decrease of androstenedione formation. The stimulatory effect of LH on steroidogenesis in vitro is discussed in relation to the literature suggesting that mammalian FSH, but not LH, stimulates all phases of reptilian ovarian function when injected in vivo.

A PRIMING EFFECT OF LUTEINIZING HORMONE RELEASING FACTOR WITH RESPECT TO RELEASE OF FOLLICLE-STIMULATING HORMONE IN VITRO AND IN VIVO

1977 ◽  
Vol 75 (1) ◽  
pp. 155-159 ◽  
Author(s):  
A. J. M. C. PICKERING ◽  
G. FINK
Keyword(s):  
Protein Synthesis ◽  
Luteinizing Hormone ◽  
Priming Effect ◽  
Follicle Stimulating Hormone ◽  
Stimulating Hormone

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.

scholarly journals Recombinant forms of rat and human luteinizing hormone and follicle-stimulating hormone; comparison of functions in vitro and in vivo

1998 ◽  
Vol 158 (3) ◽  
pp. 441-448 ◽  
Author(s):  
K Hakola ◽  
AM Haavisto ◽  
DD Pierroz ◽  
A Aebi ◽  
A Rannikko ◽  
...  
Keyword(s):  
Luteinizing Hormone ◽  
Cell Line ◽  
Follicle Stimulating Hormone ◽  
Tumor Cell Line ◽  
Male Rats ◽  
Rat Pituitary ◽  
Functional Features ◽  
Stimulating Hormone

We have previously described the preparation, purification and partial characterization of recombinant (rec) forms of rat luteinizing hormone (LH) and follicle-stimulating hormone (FSH). In the present study, the special functional features of these hormones were studied further, in vitro and in vivo, and compared with human recLH and recFSH, as well as with human urinary choriongonadotropin (hCG) and rat pituitary LH (NIDDK-RP3). In radioreceptor assay, the affinity of hCG binding to rat testis membranes was 5-fold higher than that of human recLH and 100-fold higher than that of rat recLH. In in vitro bioassay, using dispersed adult mouse interstitial cells or a mouse Leydig tumor cell line (BLT-1), hCG and human recLH were 10- to 20-fold more potent than rat recLH. Correspondingly, rat pituitary LH was about 10-fold less potent than rat recLH, and evoked a maximum testosterone response that was about half of that elicited by the other LH/CG preparations. Rat recFSH was about 10-fold less potent than human recFSH in stimulating cAMP production of a mouse Sertoli cell line (MSC-1) expressing the recombinant rat FSH receptor. The circulating half-times (T1/2) of rat and human rec hormones were assessed after i.v. injections into adult male rats rendered gonadotropin-deficient by treatment with a gonadotropin-releasing hormone antagonist. A novel immunometric assay was used for the rat FSH measurements. In the one-component model the T1/2 values of rat and human recLH were 18.2 +/- 1.9 min (n = 7) and 44.6 +/- 3.1 min (n = 7) respectively and those of rat and human recFSH were 88.4 +/- 10.7 min (n = 6) and 55.0 +/- 4.2 min (n = 6) respectively; the two-component models revealed similar differences between the rec hormone preparations. Collectively, rat recLH was eliminated significantly faster from the circulation than human recLH (P < 0.0001). In contrast, the elimination of rat recFSH was significantly slower than that of human recFSH (P = 0.02). In conclusion, rat recFSH and rat recLH display lower biopotencies per unit mass than the respective human hormones in vitro, and also in vivo for LH. This is paralleled by shorter T1/2 of rat recLH than the respective human hormone in the circulation, whereas human recFSH has a shorter T1/2 than human FSH. The special functional features of the rat rec gonadotropins emphasize the use of these preparations on studies of gonadotropin function in the rat, an important animal model for reproductive physiology.

THE EFFECTS OF SYNTHETIC GONADOTROPHIN RELEASING FACTOR ON THE RELEASE OF LUTEINIZING HORMONE AND FOLLICLE-STIMULATING HORMONE FROM OVINE PITUITARY TISSUE IN VITRO

1973 ◽  
Vol 58 (3) ◽  
pp. 387-391 ◽  
Author(s):  
D. B. CRIGHTON
Keyword(s):  
Luteinizing Hormone ◽  
Incubation Medium ◽  
Synthetic Peptides ◽  
Follicle Stimulating Hormone ◽  
The Other ◽  
Pituitary Tissue ◽  
Incubation System ◽  
Stimulating Hormone

SUMMARY A synthetic decapeptide gonadotrophin releasing factor was tested for effects on the release of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) using an ovine pituitary incubation system. The effects of other synthetic peptides used at similar doses were studied. The synthetic decapeptide consistently provoked significant increases in the LH content of the incubation medium at doses equal to or in excess of 0·5 ng/flask (0·2 ng/ml medium). Significant increases in the FSH content of the incubation medium at doses equal to or in excess of 0·25 ng/flask (0·1 ng/ml medium) were observed. The other synthetic peptides failed to influence LH or FSH release in vitro even at a dose 20–40 times greater. The results demonstrate that the decapeptide releases both LH and FSH from sheep pituitary tissue, suggesting that it may play a role in the release of both hormones in vivo in the sheep.

scholarly journals The ratio of exogenous Luteinizing hormone to Follicle stimulating hormone administered for controlled ovarian stimulation is associated with oocytes’ number and competence

2020 ◽  
Vol 40 (1) ◽  
Author(s):  
Dragos Albu ◽  
Alice Albu
Keyword(s):  
Luteinizing Hormone ◽  
Ovarian Stimulation ◽  
Follicle Stimulating Hormone ◽  
Fertilization Rate ◽  
Controlled Ovarian Stimulation ◽  
Human Menopausal Gonadotropin ◽  
Male Factor ◽  
Entire Study ◽  
Stimulating Hormone

Abstract We performed a retrospective study aiming to study the relationship between the ratio of the exogenous luteinizing hormone to follicle stimulating hormone (LH/FSH) administrated for controlled ovarian stimulation (COS) and the number and competence of the oocytes retrieved for in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI). Eight hundred sixty-eight consecutive infertile patients (mean age 34.54 ± 4.01 years, mean anti-Müllerian hormone (AMH) 2.94 ± 2.07 ng/ml) treated with long agonist protocol and a mixed gonadotropin protocol (human menopausal gonadotropin in association with recombinant FSH (recFSH)) who performed IVF/ICSI between January 2013 and February 2016, were included. Patients with severe male factor were excluded. LH/FSH was calculated based on total doses of the two gonadotropins. We found, after adjustment for confounders, a positive relationship between LH/FSH and the retrieved oocytes’ (β = 0.229, P&lt;0.0001) and zygotes’ number (β = 0.144, P&lt;0.0001) in the entire study group and in subgroups according to age (&lt;35 and ≥35 years) and ovarian reserve (AMH &lt; 1.1 and ≥ 1.1 ng/ml). The fertilization rate was positively associated with LH/FSH in patients with LH/FSH in the lowest three quartiles (below 0.77) (β = 0.096, P=0.034). However, patients in the fourth quartile of LH/FSH had a lower fertilization rate as compared with patients in quartiles 1–3 which, after adjustment for covariates, was only marginally negatively related with LH/FSH (β = −0.108, P=0.05). In conclusion, our results suggest that the adequate LH/FSH administrated during COS can improve the oocytes’ and zygotes’ number in IVF/ICSI cycles, but also the fertilization rate when a certain proportion of LH/FSH is not exceeded.

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