Exit of inhibin-like bioactivity from gonadotropin-stimulated prepubertal pig ovaries

1988 ◽  
Vol 117 (1) ◽  
pp. 39-44 ◽  
Author(s):  
M. R. Sairam ◽  
B. R. Downey

Abstract. Inhibin-like bioactivity (IBA) was assessed by bioassay in the follicular fluid, ovarian venous plasma, and peripheral plasma of immature gilts in which follicular development had been synchronized by administration of pregnant mare serum gonadotropin (PMSG) and hCG. IBA was detectable in the pooled follicular fluid of control animals, but the concentration as well as the total content increased markedly with the growth of the follicle induced by PMSG. About 36–72 h after PMSG treatment, IBA was found consistently in the venous plasma of both ovaries, although in controls as well as after ovulation (i.e. +48 h after hCG) IBA was not detected. The amount of IBA exiting the ovary by way of venous circulation was only a small fraction (< 1%) of the total activity calculated to be in each ovary at a given time. IBA was undetectable in the peripheral plasma at any sampling time. On the basis of these results we could speculate that other routes of entry of inhibin into peripheral circulation may exist in the immature pig and/or that the predominant action of IBA might be within the follicle itself.

1974 ◽  
Vol 77 (3) ◽  
pp. 575-587 ◽  
Author(s):  
F. H. de Jong ◽  
D. T. Baird ◽  
H. J. van der Molen

ABSTRACT The concentrations of oestradiol-17β, oestrone, androstenedione, testosterone, dehydroepiandrosterone, dehydroepiandrosterone sulphate and progesterone were measured in ovarian venous plasma from one or both ovaries in 4 normal women during different stages of the menstrual cycle and in 4 women with persistent ovarian follicles. In addition the steroid concentrations in peripheral plasma and follicular fluid were estimated. All steroids mentioned, with the exception of dehydroepiandrosterone sulphate, were secreted by the ovaries. The concentrations of oestradiol-17β, oestrone, androstenedione and progesterone were higher in the venous plasma from the ovary containing the developing follicle or corpus luteum than in venous plasma from the contralateral ovary. There was a good correlation between ovarian secretion of the oestrogenic steroids and androstenedione. Finally, the quantitative contribution of the ovarian secretion to the blood production rates of the androgens and progesterone was calculated. The only contributions exceeding 20 % of the blood production rate were those of progesterone and androstenedione during the second half of the cycle.


1989 ◽  
Vol 6 (4) ◽  
pp. 371-378
Author(s):  
William B. Wehrenberg ◽  
Sheddrick Fowler ◽  
John Kurhajec ◽  
Reinhold J. Hutz

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Amin Tamadon ◽  
Alireza Raayat Jahromi ◽  
Farhad Rahmanifar ◽  
Mohammad Ayaseh ◽  
Omid Koohi-Hosseinabadi ◽  
...  

The effect of superovulation by pregnant mare serum gonadotropin (PMSG) on autologous transplanted ovaries in the lumbar muscles of mice was histomorphometrically evaluated using the indices of number and volume of different kind of follicles and volume of corpora lutea, ovary, and stroma. Angiogenesis was observed after mouse ovarian transplantation on days 14 and 21 after ovarian grafting. After transplantation, the total number and volume of primary and secondary follicles reduced, while PMSG superovulation increased the total number and total volume of tertiary follicles and also the ovarian volume after transplantation. Transplantation increased the average size of primary, secondary, and tertiary follicles. Therefore, primary and secondary follicles can survive after autologous transplantation but their reservations diminished by increasing the time of transplantation. However, number of tertiary follicles and their response to superovulation increased over time after transplantation.


1976 ◽  
Vol 71 (1) ◽  
pp. 77-85 ◽  
Author(s):  
K. P. McNATTY ◽  
D. T. BAIRD ◽  
A. BOLTON ◽  
P. CHAMBERS ◽  
C. S. CORKER ◽  
...  

SUMMARY The concentrations of androstenedione, testosterone, oestrone and oestradiol-17β were measured in peripheral and ovarian venous blood and follicular fluid of women at various stages of the menstrual cycle. The concentration of oestradiol was similar in small follicles (diameter < 8 mm) at all stages of the menstrual cycle and in large follicles (diameter ⩾ 8 mm) except during the mid- and late follicular phase when the concentration reached a peak (∼ 1500 ng/ml). The concentration of androstenedione was lowest in large preovulatory follicles at mid-cycle at a time when the secretion into the ovarian vein was markedly increased. The concentration of testosterone in large follicles (⩾ 8 mm) was unchanged during the follicular phase whereas in small follicles there was a peak at mid-cycle. The rise in the concentration of testosterone and androstenedione at mid-cycle in peripheral plasma may be due to increased secretion by the preovulatory follicle into the ovarian vein. It is suggested that the relatively low concentration of androstenedione in follicular fluid of the preovulatory follicle arises from increased aromatization by granulosa cells in the course of oestrogen synthesis.


Reproduction ◽  
2000 ◽  
pp. 311-323 ◽  
Author(s):  
JL Hilton ◽  
GE Sarty ◽  
GP Adams ◽  
RA Pierson

The magnetic resonance images and maps of bovine ovaries acquired at defined phases of follicular development and regression were studied to determine whether magnetic resonance image attributes of the follicular antrum reflect the physiological status of dominant and subordinate ovarian follicles. Ovariectomies were performed at day 3 of wave one, day 6 of wave one, day 1 of wave two and at >/= day 17 after ovulation. The timings of ovariectomies were selected to acquire growing, early static, late static and regressing follicles of the first wave and preovulatory follicles of the ovulatory wave. Pre-selection and subordinate follicles were also available for analysis. Serum samples were taken on the day of ovariectomy and follicular fluid samples were taken after imaging. Numerical pixel value and pixel heterogeneity in a spot representing approximately 95% of the follicular antrum were quantified in T(1)- and T(2)-weighted images. T(1) and T(2) relaxation rates (T(1) and T(2)), proton density, apparent diffusion coefficients and their heterogeneities were determined from the computed magnetic resonance maps. The antra of early atretic dominant follicles showed higher T(2)-weighted mean pixel value (P < 0.008) and heterogeneity (P < 0. 01) and lower T(2) heterogeneity (P < 0.008) than growing follicles. Subordinate follicles in the presence of a preovulatory dominant follicle had higher T(1), T(1) heterogeneity, proton density, proton density heterogeneity, and lower mean pixel value in T(1)-weighted images than subordinate follicles of the anovulatory wave (P < 0.04). T(1) relaxation rate heterogeneity and proton density heterogeneity were positively correlated with follicular fluid oestradiol concentration (r = 0.4 and 0.3; P < 0.04). T(2) relaxation rate heterogeneity was positively correlated with follicular fluid progesterone concentration (r = 0.4; P < 0.008). Quantitative differences in magnetic resonance image attributes of the antrum observed among phases of follicular development and regression coincided with changes in the ability of the dominant follicle to produce steroid hormones and ovulate, and thus were indicative of physiological status and follicular health.


1975 ◽  
Vol 64 (3) ◽  
pp. 555-571 ◽  
Author(s):  
K. P. McNATTY ◽  
W. M. HUNTER ◽  
A. S. McNEILLY ◽  
R. S. SAWERS

SUMMARY The concentrations of FSH, LH, prolactin, oestradiol and progesterone were measured in peripheral plasma and follicular fluid of women throughout the menstrual cycle. With the exception of prolactin, concentrations of pituitary and steroid hormones in follicular fluid correlated with those in peripheral plasma. Follicle-stimulating hormone was present in a greater number of small follicles ( < 8 mm) during or just after the peaks of FSH in peripheral plasma. During the mid-follicular phase the concentration of both FSH and oestradiol in fluid from large follicles ( ≥ 8 mm) was high. During the late follicular phase the large follicles ( ≥ 8 mm) contained high amounts of progesterone in addition to oestradiol, low physiological levels of prolactin, and concentrations of LH and FSH about 30 and 60% respectively of those found in plasma. By contrast no large 'active' follicles ( ≥ 8 mm) were found during the luteal phase although many contained both LH and FSH. Luteinizing hormone was present in a proportion of small follicles ( < 8 mm) during the late follicular and early luteal but not at other stages of the menstrual cycle. It is suggested that a precise sequence of hormonal changes occur within the microenvironment of the developing Graafian follicle; the order in which they occur may be of considerable importance for the growth of that follicle and secretory activity of the granulosa cells both before and after ovulation.


2014 ◽  
Vol 998-999 ◽  
pp. 228-232
Author(s):  
Zheng Hong Zhang ◽  
Fan Wang ◽  
Yan Qing Wu ◽  
Zong Hao Tang ◽  
Qing Qiang Lin ◽  
...  

Echinomycin (Ech) is a small-molecule inhibitor of hypoxia-inducible factor-1 DNA-binding activity, which plays a crucial role in the regulation of ovarian functions in mammals. The present study was designed to test the hypothesis that hypoxia-inducible factor (HIF)-1alpha-mediated proliferation cell nuclear antigen (PCNA) expressions contributed to the follicular development in the rat ovary primed by pregnant mare serum gonadotropin (PMSG). Through the histological examination, the decrease of growing and antral follicle numbers was found after Ech treatment both in control and PMSG treated groups. And then PCNA mRNA and protein expressions were found to significantly increase in the ovaries treated with PMSG, and the similar changes were found in HIF-1alpha mRNA and protein expressions, indicating PMSG-induced follicular development may be through HIF-1alpha/PCNA signaling. Furthermore, PCNA expression was found to significantly decrease in the ovaries after Ech treatment, while HIF-1alpha mRNA and protein expression was no obviously changes. Further analysis found the changes of PCNA expression were consistent with HIF-1 activity in the ovaries, further suggesting the regulatory roles in the follicular development. Taken together, these results demonstrated this HIF-1alpha-mediated PCNA expression is one of the important mechanisms regulating the ovarian follicular development in mammals. Keywords: HIF-1alpha; PCNA; echinomycin; HIF prolyl hyodroxylase acitvity; follicular development


1992 ◽  
Vol 8 (3) ◽  
pp. 217-224 ◽  
Author(s):  
R.J. Pendleton ◽  
C.R. Youngs ◽  
R.W. Rorie ◽  
S.H. Pool ◽  
M.A. Memon ◽  
...  

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