Possible existence of a long-loop feedback system between FSH and inhibin in female rats

1981 ◽  
Vol 240 (5) ◽  
pp. E544-E549 ◽  
Author(s):  
L. V. DePaolo ◽  
L. D. Anderson ◽  
A. N. Hirshfield
Keyword(s):  
Follicle Stimulating Hormone ◽  
Feedback System ◽  
Female Rats ◽  
Time Interval ◽  
Ether Anesthesia ◽  
Peripheral Plasma ◽  
Loop Feedback ◽  
Ovarian Inhibin ◽  
Venous Plasma

Experiments were designed in which peripheral plasma inhibin levels were presumably altered in an attempt to investigate an interdependency between pituitary follicle-stimulating hormone (FSH) and ovarian inhibin secretion. In the first study, unilateral ovariectomy (ULO) was performed on 4-day cycling female rats under ether anesthesia at 0800 h on diestrous day 1 (D1). Inhibin-like activity [FSH-inhibiting activity(FSH-IA)] in untreated ovarian venous plasma (OVP) collected from the remaining ovary was assessed by an in vitro pituitary bioassay system. Both plasma FSH levels and FSH-IA significantly increased between 4 and 12 h after ULO. Thereafter, plasma FSH declined between 12 and 32 h after ULO, whereas FSH-IA remained elevated during this same time interval. Compared to sham-operated rats, plasma FSH was significantly elevated 4, 12, and 24 h after ULO, whereas FSH-IA was statistically higher only at 32 h after ULO. In a second experiment, rats were injected with charcoal-treated porcine follicular fluid (PFF) on proestrus and estrus. Control rats received saline. The data indicate that increased plasma FSH levels on D1 in PFF-treated rats (FSH rebound) may be a consequence of reduced endogenous inhibin secretion on estrus. As well, return of FSH to control levels on D2 in PFF-treated rats may have resulted from an FSH-associated increase in FSH-IA on D1 and D2.

Inhibin increases in the ovaries of female rats approaching first ovulation: relationships with follicle growth and serum FSH concentrations

1986 ◽  
Vol 111 (1) ◽  
pp. 159-166 ◽  
Author(s):  
H. J. Sander ◽  
H. M. A. Meijs-Roelofs ◽  
E. C. M. van Leeuwen ◽  
P. Kramer ◽  
W. A. van Cappellen
Keyword(s):  
Female Rats ◽  
Time Interval ◽  
Pituitary Cells ◽  
In Vitro Bioassay ◽  
Unilateral Ovariectomy ◽  
Adult Rat ◽  
Fine Regulation ◽  
Subsequent Measurement ◽  
Ovarian Inhibin

ABSTRACT In order to relate various prepubertal events in a group of 95 late prepubertal female rats, the following data were obtained during the last 10 days before the day of first ovulation: (1) amounts of ovarian inhibin-like activity (ILA) in some animals (n=47); (2) size and numbers of healthy (antral) follicles with a volume ≥100× 105 μm3 (or diameter ≥260 μm) present per ovary in their litter-mates (n=48); (3) serum FSH concentrations in both groups. Rats were unilaterally ovariectomized to obtain an ovary for either estimation of ILA content or for histological procedures and counting of follicles. At the time of unilateral ovariectomy they were bled to obtain serum for estimation of FSH concentrations. Rats were kept until the day after the day of first ovulation to determine the time-interval between the day of unilateral ovariectomy and first ovulation. They were studied between 10 and 1 days (days −10 to − 1, maturational age) before first ovulation. In addition, adult cyclic rats were bilaterally ovariectomized on different days of the oestrous cycle for estimation of ovarian ILA content. The amount of ovarian ILA was estimated in steroid-free ovarian cytosols using an in-vitro bioassay system with dispersed anterior pituitary cells and subsequent measurement of FSH and LH in the spent medium. The amount of ovarian ILA was about 83 units/ ovary from days −10 to −5, and subsequently increased (P < 0·005) to reach a maximum on day − 1, the day of pro-oestrus (213 units/ovary). Inhibin-like activity in adult rat ovaries at pro-oestrus amounted to 374 units/ovary. A significant relationship was found between ovarian ILA content and total volume of follicles of classes III–V (≥350 × 105 μm3) (r= 0·9683, P<0·005) except for the period between days −7 and −5 when this volume increased earlier than did the ILA content. The total volume of all follicles ≥ 100 × 105 μm3 was steady from days −10 to −7. On day −6 this volume increased, mainly as a result of an increase of total volume of class II follicles. Thereafter, the total volume of follicles in classes III–V started to increase and was maximal on day −1, while the total volume of follicles in classes I plus II decreased and reached a minimum on day −1. The serum FSH concentration declined between days −10 and −1 from 400 to 100 μg/l (P<0·001); the presence of follicles of classes III–V was always associated with FSH concentrations ≤200 μg/l (P<0·005). The presence of class I and II follicles was not related to FSH concentrations. This suggested that mainly follicles of classes III–V contribute to ovarian ILA. The present data show that in immature rats ovarian ILA content increases towards the day of first pro-oestrus, as it does later during pro-oestrus in adult cyclic rats. Inhibin-like activity seems to be produced mainly by follicles of classes III–V which are present in the ovaries during the last 5 days preceding first ovulation. In this same period FSH concentrations are kept within narrow limits (<200 μg/l) as is the case during the adult cycle. Thus, ILA probably plays a role in the fine regulation of FSH secretion. J. Endocr. (1986) 111, 159–166

EFFECT OF OVINE LUTEINIZING HORMONE ON THE SECRETION OF PROGESTERONE IN VITRO BY OVARIAN FOLLICLES FROM HYPOPHYSECTOMIZED RATS TREATED WITH FOLLICLE-STIMULATING HORMONE

1978 ◽  
Vol 77 (3) ◽  
pp. 419-420
Author(s):  
A. R. LABARBERA ◽  
MERO R. NOCENTI
Keyword(s):  
New York ◽  
Luteinizing Hormone ◽  
Corn Oil ◽  
Follicle Stimulating Hormone ◽  
Virgin Female ◽  
Ovarian Follicles ◽  
Female Rats ◽  
Hypophysectomized Rats ◽  
Stimulating Hormone

Department of Physiology, College of Physicians and Surgeons, Columbia University, New York 10032, U.S.A. (Received 14 November 1977) Ovarian follicles from oestrous, pro-oestrous and hypophysectomized rats have the capacity to secrete progestins in vitro and to respond to luteinizing hormone (LH) by increasing this secretion (Stoklosowa & Nalbandov, 1972; LaBarbera, Nocenti & Castellano, 1974; Lindner, Tsafriri, Lieberman, Zor, Koch, Bauminger & Barnea, 1974). Follicles from hypophysectomized rats, untreated or treated with follicle-stimulating hormone (FSH), were therefore studied in experiments in vitro to investigate further the gonadotrophic control of progesterone secretion. Mature virgin female rats (200–250 g) were hypophysectomized and, beginning on day 4 after the operation, received a total of 360 μg ovine FSH (NIH-FSH-S9)/100 g body weight, injected s.c. in corn oil as six divided doses, one every 12 h for 3 days. Untreated controls received corn oil only. On day 7 after hypophysectomy, the ovaries were excised and

Inhibin, a member of a new peptide family

1989 ◽  
Vol 1 (1) ◽  
pp. 1 ◽  
Author(s):  
HG Burger
Keyword(s):  
Feedback System ◽  
Suppressive Effect ◽  
Commercial Application ◽  
Pituitary Cells ◽  
Cell Content ◽  
Peptide Family ◽  
Normal Menstrual Cycle ◽  
Loop Feedback

There is considerable experimental evidence that follicle stimulating hormone (FSH) and luteinizing hormone (LH) are regulated by separate mechanisms in some circumstances. Part of this differential regulation involves the gonadal factor inhibin, which preferentially affects FSH. A sensitive and specific bioassay based on suppression of FSH cell content in dispersed cultured pituitary cells was used to monitor the purification of inhibin to homogeneity. The two subunits were cloned and the full amino acid sequence of the molecule established. Much evidence has been gathered to support the hypothesis that FSH and inhibin form a classic endocrine closed-loop feedback system in which FSH stimulates inhibin secretion both in vivo and in vitro and inhibin in turn exerts a significant suppressive effect on FSH secretion. The establishment of an inhibin radioimmunoassay has allowed the description of its concentrations in various physiological states such as in the normal menstrual cycle, during puberty and in pregnancy. Inhibin levels were shown to be within the normal range in the polycystic ovarian syndrome. A potential commercial application of inhibin is as a vaccine to increase fertility in domestic animals.

Mechanisms responsible for suppression of FSH and LH during lactation in the rat

1991 ◽  
Vol 129 (1) ◽  
pp. 119-130 ◽  
Author(s):  
K. Taya ◽  
S. Sasamoto
Keyword(s):  
Plasma Concentrations ◽  
The Other ◽  
Primary Role ◽  
Ovarian Steroids ◽  
Unilateral Ovariectomy ◽  
Peripheral Plasma ◽  
The Mean ◽  
Lh Secretion ◽  
Ovarian Inhibin ◽  
Venous Plasma

ABSTRACT Mechanisms responsible for suppression of FSH and LH secretion during lactation were investigated in rats, with special reference to the suckling stimulus and ovarian inhibin. Concentrations of immunoreactive inhibin in the peripheral plasma and bioactive inhibin in ovarian venous plasma were always low on days 3 and 5 of lactation in dams nursing eight pups, whereas values were always high on days 17 and 20 of lactation in dams nursing eight pups and on day 5 of lactation in dams nursing two pups. There was an FSH surge within 48 h after removal of litters on days 3 and 5 of lactation in dams nursing eight pups, whereas plasma concentrations of FSH were unchanged within 48 h by removal of litters on days 17 and 20 of lactation in dams nursing eight pups and on day 5 of lactation in dams nursing two pups. Plasma LH concentrations increased significantly compared with those of control animals within 24 h after removal of the litter on any day of lactation, regardless of the litter size. Plasma FSH levels increased within 6 h after bilateral or unilateral ovariectomy in lactating rats only on the days when plasma concentrations of inhibin were high before ovariectomy, such as day 17 of lactation in dams nursing eight pups and on day 5 of lactation in dams nursing two pups, whereas the mean concentrations of plasma LH showed no significant increase within 12 h after bilateral ovariectomy in these lactating rats. Treatment with progesterone or oestradiol-17β after unilateral ovariectomy did not inhibit the increase in plasma FSH levels, while the increase in plasma concentrations of FSH after surgery was completely inhibited by injecting inhibin (porcine follicular fluid). Treatment with steroid hormones inhibited the basal levels of LH in unilateral ovariectomized lactating rats. Plasma FSH concentrations increased sharply within 6 h after a single i.v. injection of anti-inhibin serum on days 10, 15 and 20 of lactation in dams nursing eight pups and on day 5 of lactation in dams nursing two pups, whereas only a small but significant increase in concentrations of FSH was noted 6 h after the antiserum treatment on day 5 of lactation in dams nursing eight pups. Concentrations of plasma LH were unchanged by treatment with antiserum in lactating rats throughout lactation. These findings indicate that the suckling stimulus, rather than ovarian factors, is mainly responsible for the suppression of FSH as well as LH secretion during the first half of lactation in rats nursing eight pups. On the other hand, during the second half of lactation in rats nursing eight pups and throughout lactation in rats nursing two pups, ovarian inhibin plays a primary role in the suppression of FSH secretion, whereas ovarian steroids act to suppress LH secretion. Journal of Endocrinology (1991) 129, 119–130

scholarly journals In vitro evaluation of a closed-loop feedback system for dopamine concentration control

2015 ◽  
Vol 31 (1) ◽  
pp. 26-32 ◽  
Author(s):  
Carlos Eduardo de Araujo ◽  
Paulo José Abatti ◽  
Cláudio Da Cunha ◽  
Alexander Gómez ◽  
Patrícia Andréia Dombrowski
Keyword(s):  
Closed Loop ◽  
Feedback System ◽  
In Vitro Evaluation ◽  
Dopamine Concentration ◽  
Loop Feedback ◽  
Closed Loop Feedback

Effects of LHRH and ANG II on prolactin stimulation are mediated by hypophysial AT1 receptor subtype

1994 ◽  
Vol 266 (2) ◽  
pp. E274-E278 ◽  
Author(s):  
D. Becu-Villalobos ◽  
I. M. Lacau-Mengido ◽  
S. M. Thyssen ◽  
G. S. Diaz-Torga ◽  
C. Libertun
Keyword(s):  
Luteinizing Hormone ◽  
Follicle Stimulating Hormone ◽  
Female Rats ◽  
Receptor Subtype ◽  
Receptor Subtypes ◽  
Ang Ii ◽  
Prolactin Release ◽  
Luteinizing Hormone Releasing Hormone ◽  
Prolactin Response

We have used the nonpeptide angiotensin II (ANG II) receptor antagonists losartan (receptor subtype AT1) and PD-123319 (AT2) to determine the participation of ANG II receptor subtypes in luteinizing hormone-releasing hormone (LHRH)-induced prolactin release in a perifusion study using intact pituitaries in vitro. LHRH (1.85 x 10(-7) M) released prolactin consistently, whereas losartan (10(-5) M) abolished prolactin response without modifying basal prolactin or luteinizing hormone (LH) and follicle-stimulating hormone (FSH) release. PD-123319 (10(-5) M) had no effect on basal or LHRH-induced prolactin, LH, or FSH release. We also determined that the effect of ANG II on prolactin release was mediated by the same receptor subtype. In adenohypophysial cells dispersed in vitro ANG II (10(-8) M) released prolactin. Losartan (10(-7) and 10(-6) M), but not PD-123319, inhibited this effect. We conclude that in intact hypophyses of 15-day-old female rats the effect of LHRH on prolactin release is readily demonstrated. LHRH-induced prolactin release appears to be mediated by ANG II acting in a paracrine manner on AT1 receptors located on lactotrophs.

Short Loop Feedback System for the Control of Follicle-Stimulating Hormone in the Rabbit*

Endocrinology ◽  
1981 ◽  
Vol 108 (1) ◽  
pp. 72-75 ◽  
Author(s):  
NILSA PATRITTI LABORDE ◽  
ADA R WOLFSEN ◽  
WILLIAM D. ODELL
Keyword(s):  
Follicle Stimulating Hormone ◽  
Feedback System ◽  
Short Loop ◽  
Loop Feedback ◽  
Stimulating Hormone

scholarly journals Ovarian Folliculogenesis and Uterine Endometrial Receptivity after Intermittent Vaginal Injection of Recombinant Human Follicle-Stimulating Hormone in Infertile Women Receiving In Vitro Fertilization and in Immature Female Rats

2021 ◽  
Vol 22 (19) ◽  
pp. 10769
Author(s):  
Chao-Chin Hsu ◽  
Leonard Hsu ◽  
Yuan-Shuo Hsueh ◽  
Chih-Ying Lin ◽  
Hui Hua Chang ◽  
...  
Keyword(s):  
In Vitro Fertilization ◽  
Follicle Stimulating Hormone ◽  
Endometrial Receptivity ◽  
Female Rats ◽  
Daily Injection ◽  
Immature Female ◽  
Vitro Fertilization ◽  
Ovarian Folliculogenesis ◽  
Stimulating Hormone

The uterine first-pass effect occurs when drugs are delivered vaginally. However, the effect of vaginally administered recombinant human follicle-stimulating hormone (rhFSH) on ovarian folliculogenesis and endometrial receptivity is not well established. We aimed to compare the efficacy of rhFSH administered vaginally and abdominally in clinical in vitro fertilization (IVF) treatment, pharmacokinetic study, and animal study. In IVF treatment, the number of oocytes retrieved, endometrial thickness and uterine artery blood perfusion were not different between women who received the rhFSH either vaginally or abdominally. For serum pharmacokinetic parameters, significantly lower Tmax, clearance, and higher AUC and T1/2_elimination of rhFSH were observed in women who received rhFSH vaginally, but urine parameters were not different. Immature female rats that received daily abdominal or vaginal injections (1 IU twice daily for 4 days) or intermittent vaginal injections (4 IU every other day for two doses) of rhFSH had more total follicles than the control group. In addition, the serum progesterone and progesterone receptors in the local endometrium were significantly higher in the groups treated with intermittent abdominal or vaginal injection of rhFSH, compared with those who recieved daily injection. In summary, vaginal administration of rhFSH may provide an alternative treatment regimen in women receiving IVF.

EFFECT OF GONADOTROPHINS ON THE SECRETION OF OESTRADIOL-17β AND TESTOSTERONE BY THE RAT TESTIS

1973 ◽  
Vol 57 (2) ◽  
pp. 277-284 ◽  
Author(s):  
F. H. DE JONG ◽  
A. H. HEY ◽  
H. J. van der MOLEN
Keyword(s):  
Intravenous Administration ◽  
Adult Male ◽  
Follicle Stimulating Hormone ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Male Rats ◽  
Testosterone Concentration ◽  
Peripheral Plasma ◽  
Before And After ◽  
Venous Plasma

SUMMARY Concentrations of oestradiol-17β and testosterone were estimated in peripheral venous plasma and testicular venous plasma of adult male rats before and after administration of human chorionic gonadotrophin (HCG) or follicle-stimulating hormone (FSH). The concentration of oestradiol-17β in peripheral plasma, as measured with a radioimmunological technique, was 2·0 ± 0·9 (s.d.) pg/ml (n = 12). Peripheral testosterone concentrations were 2·4 ± 1·8 (s.d.) ng/ml (n = 21). Concentrations of oestradiol-17β and testosterone in testicular venous plasma were significantly higher than those in peripheral plasma. After intravenous administration of HCG (100 i.u.), oestradiol-17β and testosterone concentrations in testicular venous plasma increased significantly. After prolonged s.c. administration of HCG (5 days) the concentration of oestradiol-17β in testicular venous plasma did not change significantly, although the concentration of testosterone increased more than ten times. Intravenous administration of HCG after 5 days of pretreatment with HCG caused a significant increase in oestradiol-17β concentrations in testicular venous plasma. The increase in testosterone concentration was not significant under these conditions. Intravenous administration of FSH did not change oestradiol-17β or testosterone concentrations in testicular venous plasma.

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