105 Proteome profiling of equine follicular fluid before, during, and after selection of the dominant follicle

2022 ◽  
Vol 34 (2) ◽  
pp. 289
Author(s):  
J. Feugang ◽  
G. Ishak ◽  
T. Pechan ◽  
O. Pechanova ◽  
M. Gastal ◽  
...  
Reproduction ◽  
2001 ◽  
pp. 561-569 ◽  
Author(s):  
FM Rhodes ◽  
AJ Peterson ◽  
PD Jolly

The aim of this study was to examine the function of granulosa cells and hormone concentrations in follicular fluid in bovine ovarian follicles during selection of the first dominant follicle. Ovaries were obtained from beef heifers on days 1-5 after ovulation: follicles > 4 mm in diameter were dissected and follicular fluid and granulosa cells were collected from individual follicles. Oestradiol production by granulosa cells after culture with testosterone was used to determine aromatase activity and responsiveness to gonadotrophins was determined by cAMP production after culture with FSH or LH. Concentrations of oestradiol, progesterone and insulin-like growth factor binding proteins (IGFBPs)-4 and -5 were measured in follicular fluid. Follicles were classified as largest or smaller (days 1 and 2), or dominant or subordinate (days 3-5). Aromatase activity was greater in granulosa cells from the largest follicle than in granulosa cells from smaller follicles on days 1, 3, 4 and 5 (P < 0.05). Responsiveness to LH was not detected in granulosa cells on day 1, but from day 2 to day 5 cells from the largest follicle were significantly more responsive than cells from smaller follicles (P < 0.05). Responsiveness to FSH was detected in granulosa cells from all follicles from day 1 onwards and did not differ between cells from the largest follicle or smaller follicles on any day. Follicular fluid concentrations of oestradiol and the ratio of oestradiol:progesterone were greater and concentrations of IGFBP-4 and -5 were lower in the largest follicle than in smaller follicles from day 2 to day 5 (P < 0.05). In conclusion, selection of the dominant follicle is associated with increased granulosa cell aromatase activity followed by increased cAMP response to LH and follicular fluid oestradiol concentrations, and decreased follicular fluid concentrations of IGFBP-4 and -5 within 2 days after ovulation.


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.


2020 ◽  
Vol 32 (3) ◽  
pp. 322 ◽  
Author(s):  
Jin G. Gong ◽  
Bruce K. Campbell ◽  
Robert Webb

The aim was to define the pattern and physiological concentrations of FSH and LH required for the selection of a single dominant follicle in mono-ovulatory species. A series of five experiments was carried out using gonadotrophin-releasing hormone agonist-induced hypogonadal heifers. Animals were infused with different patterns of either FSH and/or LH followed by an ovulatory dose of human chorionic gonadotrophin. Follicular response was monitored by ultrasound scanning and blood samples were collected to measure concentrations of FSH, LH, oestradiol and progesterone. The main findings were: (1) physiological concentrations of FSH given as a continuous infusion and for an adequate duration, in the presence of basal LH, with or without LH pulses, are capable of inducing a superovulatory response, (2) initial exposure to FSH followed by LH pulses alone stimulate the development of multiple preovulatory follicles, confirming that ovarian follicles are capable of transferring dependence on gonadotrophins from FSH to LH, (3) while LH pulses appear not to have a major effect on the pattern of preovulatory follicle development, adequate LH pulsatile support is required for full oestradiol synthesis and (4) the duration of initial exposure to FSH and the ability to transfer the dependence from FSH to LH are critical for the selection of a single dominant follicle. In conclusion, this experimental series confirms that the duration of initial exposure to FSH and the ability of the selected follicle to transfer its gonadotrophic dependence from FSH to LH are critical for the selection of a single dominant follicle in cattle.


1997 ◽  
Vol 57 (6) ◽  
pp. 1320-1327 ◽  
Author(s):  
E. L. Gastal ◽  
M. O. Gastal ◽  
D. R. Bergfelt ◽  
O. J. Ginther

2020 ◽  
Vol 32 (2) ◽  
pp. 191
Author(s):  
M. Pastorello ◽  
M. O. Gastal ◽  
G. K. Piquini ◽  
D. B. Godoi ◽  
E. L. Gastal

The mare, compared to other livestock, has the shortest interval from partum to the first ovulation. In monovulatory species, the follicle deviation process in a wave is characterised by the continued growth of the dominant follicle (DF) and regression of the subordinate follicle. Although follicle diameter deviation, a key event of follicle selection, has been investigated during the oestrous and menstrual cycles, the occurrence of this phenomenon before the first postpartum ovulation seems to be unclear in all species. This study aimed to compare the follicular dynamics and gonadotropin profiles around the follicle diameter deviation day in postpartum lactating (PP Lactating; n=24) versus non-postpartum cycling (NPP Cycling; n=15) mares. On the day of parturition, every PP Lactating mare was paired with an NPP Cycling mare, and ovarian follicles (&gt;4mm) were tracked daily by transrectal ultrasonography, and blood samples were collected. Data were analysed in the PP Lactating group according to the length of the partum-ovulation interval (POI; ≤22 and &gt;22 days) and the postpartum interovulatory interval (PPIOI), and in the NPP Cycling group during two interovulatory intervals (1st and 2nd IOI). In addition, regardless of group, all four intervals were compared. We performed the FSH and LH assays using radioimmunoassay. Ovarian and hormonal parameters were analysed using ANOVA for sequential data. The day and diameter of the DF at the deviation (overall mean: 14.9±2.5 days; 21.7±0.4mm, respectively) were not different (P&gt;0.05) between PP Lactating and NPP Cycling mares. However, when considering the length of POI, follicle deviation occurred 4.4±0.8 days earlier (P&lt;0.001) in mares with POI ≤ 22 days than in mares with POI&gt;22 days. No difference was found between PP Lactating and NPP Cycling mares within and between groups for the intervals from deviation to maximum diameter of the DF (10.4±0.4 days), for the intervals from deviation to ovulation (12.1±0.5 days), or for the growth rates of the DF from deviation to maximum diameter (2.6±0.1mm per day). The growth rate of the DF from deviation to ovulation (2.4±0.1mm per day) did not differ between PP Lactating and NNP Cycling mares; however, this growth rate was lower (P&lt;0.03) in the POI, PPIOI, and 1st IOI compared with the 2nd IOI. The mean diameter of the DF around deviation (days −3 to 3; 22.5±0.3mm), and systemic FSH (days −4 to 4; 10.3±0.2ngmL−1) were not different between PP Lactating and NPP Cycling mares. Level of LH was lower (P&lt;0.0001) around deviation (days −4 to 4) in the PP Lactating (0.7±0.0ngmL−1) versus the NPP Cycling mares (1.8±0.1ngmL−1). Results demonstrated that a partum effect occurs only on the day of deviation in mares during the foal heat (POI ≤ 22 days) and that low levels of LH during both intervals in PP Lactating mares were not detrimental to prevent ovulation.


Endocrinology ◽  
2003 ◽  
Vol 144 (2) ◽  
pp. 437-446 ◽  
Author(s):  
G. M. Rivera ◽  
J. E. Fortune

Development of a dominant follicle is associated with decreased intrafollicular low molecular weight IGF-binding proteins (namely IGFBP-2, -4, and -5) and increased proteolysis of IGFBP-4 by pregnancy-associated plasma protein A (PAPP-A). In addition to IGFBP-4 proteolytic activity, bovine follicular fluid contains strong proteolytic activity for IGFBP-5, but not for IGFBP-2. Here we show that the IGFBP-5 protease present in bovine follicular fluid is a neutral/basic pH-favoring, Zn2+ metalloprotease very similar to the previously described IGFBP-4 protease. We hypothesized that immunoneutralization and immunoprecipitation with anti-PAPP-A antibodies would result in abrogation of the IGFBP-4, but not the IGFBP-5, proteolytic activity in follicular fluid. As expected, anti-PAPP-A antibodies were able to neutralize and precipitate the IGFBP-4, but not the IGFBP-5, proteolytic activity of human pregnancy serum, which was used as a positive control for PAPP-A. Surprisingly, immunoneutralization and immunoprecipitation of follicular fluid from bovine preovulatory follicles with anti-PAPP-A antibodies abrogated both IGFBP-4 and IGFBP-5 proteolysis. Quantitative results derived from phosphorimaging revealed a complete inhibition of both IGFBP-4 and -5 proteolysis by follicular fluid incubated for 2 or 5 h in the presence of anti-PAPP-A antibodies. After 18 h of incubation, anti-PAPP-A antibodies still inhibited IGFBP-5 degradation, although with an efficiency lower than that for IGFBP-4 degradation. Both proteolytic activities have identical electrophoretic mobility, and a single band (∼400 kDa) was detected by Western immunoblotting of bovine follicular fluid with anti-PAPP-A antibodies. Proteolysis of IGFBP-5 was readily detectable in follicular fluid from dominant follicles and was negligible in subordinate follicles from the same cohort. These results suggest that an active intrafollicular IGFBP-4/-5 proteolytic system, in which PAPP-A is the major protease involved, is an important determinant of follicular fate.


1996 ◽  
Vol 55 (6) ◽  
pp. 1187-1194 ◽  
Author(s):  
O.J. Ginther ◽  
M.C. Wiltbank ◽  
P.M. Fricke ◽  
J.R. Gibbons ◽  
K. Kot

1996 ◽  
Vol 148 (2) ◽  
pp. 281-289 ◽  
Author(s):  
B R Leeuwenberg ◽  
N L Hudson ◽  
L G Moore ◽  
P R Hurst ◽  
K P McNatty

Abstract IGF-I was measured by RIA in plasma samples collected 8-hourly for 24 days which included two consecutive preovulatory surges of LH. In a separate study, ovarian venous blood was collected from animals undergoing ovariectomy on day 10 of the oestrous cycle, or 36 h later after being treated with prostaglandin with or without steroid-free bovine follicular fluid. Jugular venous blood samples were collected before, during and after surgery. Follicles were dissected from ovaries of these animals and sorted into categories of small, intermediate and large, non-atretic or atretic, and the follicular fluid was pooled and assayed for IGF-I. From another population of ovaries recovered from the slaughterhouse, granulosa, theca and corpora lutea were isolated, homogenized and assayed for IGF-I. Finally ovarian corpora lutea and granulosa cells were each incubated with tritiated amino acids overnight at 37 °C. Thereafter the tissues and media were sonicated, IGF-I extracted from the supernatant and tritiated IGF-I precipitated using a specific IGF-I antibody. The absence of any significant change in peripheral IGF-I concentrations following ovariectomy and the finding that the ovarian venous IGF-I concentrations (161 ± 10 μg/l) were not significantly different from levels seen in peripheral blood (157 ± 10 μg/l) indicated that the ovary is not a net exporter of IGF-I. However, the ovary does synthesize IGF-I, as evidenced by granulosa and luteal synthesis, but probably not in quantities in excess of that utilized by ovarian tissues per se. Although the plasma IGF-I levels increased around the second preovulatory LH surge, the results overall indicated that the IGF-I concentrations in plasma are not strictly related to any major ovarian event during the oestrous cycle in the sheep. This view is based on the findings that the concentration of IGF-I in follicular fluid was not related to follicular health but correlated with those in peripheral plasma and that the ovarian venous concentrations did not vary between left and right ovaries irrespective of whether the ovaries contained a corpus luteum, dominant follicle or neither. Collectively, these results are consistent with the notion that IGF-I of ovarian origin fulfils an autocrine/paracrine function and does not have an endocrine role. Moreover, the results show that the concentrations of IGF-I in follicular fluid reflect those in peripheral plasma. Journal of Endocrinology (1996) 148, 281–289


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