scholarly journals The FecB (Booroola) gene acts at the ovary: in vivo evidence

Reproduction ◽  
2003 ◽  
pp. 101-111 ◽  
Author(s):  
BK Campbell ◽  
DT Baird ◽  
CJ Souza ◽  
R Webb
Keyword(s):  
Venous Blood ◽  
Follicular Development ◽  
Ovarian Response ◽  
Antral Follicle ◽  
Genotypic Difference ◽  
Corpora Lutea ◽  
Normal Cycle ◽  
Gene Carriers ◽  
Standardized Treatment

The aim of this study was to differentiate between pituitary and ovarian actions of the FecB gene by measuring the ovarian response to a standardized treatment with gonadotrophins designed to mimic the changes in FSH and LH that occur in the follicular phase of the ovarian cycle in ewes, with (Fec(B/-), n=6) and without (Fec(+/+), n=9) the gene, that were rendered hypogonadotrophic by pretreatment with a potent antagonist of GnRH. Ewes with ovarian autotransplants were used to facilitate the assessment of follicular function by the collection of ovarian venous blood and ultrasonography. The gonadotrophin regimen resulted in concentrations of FSH and LH that were similar to concentrations found in a normal cycle and did not differ between genotypes. Follicular development and ovulation occurred in all animals, and patterns of secretion of oestradiol, androstenedione and inhibin A were normal. Despite these endocrine similarities, the antral follicle population stimulated by FSH infusion retained the characteristic genotypic difference with the ovaries of Fec(+/+) animals containing a range of follicle sizes with decreasing proportions of small (<3.5 mm in diameter) and medium (3.5-4.5 mm in diameter) follicles as well as large follicles (> or =4.5 mm in diameter), whereas the ovaries of Fec(B/-) ewes contained no follicles of >4.5 mm in diameter. This genotypic difference was retained after ovulation with gene carriers having more preovulatory follicles/corpora lutea (3.8+/-0.3) of a smaller diameter (5.3+/-0.3 mm) than did non-gene carriers (1.7+/-0.3; 11.4+/-0.9 mm; P<0.05). As ewes carrying the FecB gene mutation were able to ovulate more follicles than non-gene carriers, despite identical concentrations and patterns of FSH and LH stimulation, the results of this study support the hypothesis that the FecB gene acts at the ovary to enhance ovarian sensitivity to gonadotrophic stimulation.

Effect of active immunization of heifers against inhibin on plasma FSH concentrations, ovarian follicular development and ovulation rate

1992 ◽  
Vol 134 (1) ◽  
pp. 11-18 ◽  
Author(s):  
R. G. Glencross ◽  
E. C. L. Bleach ◽  
B. J. McLeod ◽  
A. J. Beard ◽  
P. G. Knight
Keyword(s):  
Synthetic Peptide ◽  
Ovarian Function ◽  
Statistical Significance ◽  
Follicular Development ◽  
Ovarian Response ◽  
Active Immunization ◽  
Ovulation Rate ◽  
Corpora Lutea ◽  
Α Subunit ◽  
Ovarian Follicular Development

ABSTRACT To study the effects of immunoneutralization of endogenous inhibin on gonadotrophin secretion and ovarian function, prepubertal heifers (n = 6) were actively immunized against a synthetic peptide replica of the N-terminal sequence of bovine inhibin α subunit bIα(1–29)Tyr30) coupled to ovalbumin. In contrast to ovalbumin-immunized controls (n=6), bIα(1–29)Tyr30-immunized heifers had detectable inhibin antibody titres (% binding to 125I-labelled bovine inhibin at 1:2000 dilution of plasma) of 17 ± 3% (s.e.m.) at puberty, rising to 31 ± 5% by the end of the study period 7 months later. Neither age (immunized: 295 ± 8 days; controls: 300 ± 5 days) nor body weight (immunized: 254 ± 13 kg; controls 251 ± 9 kg) at onset of puberty differed between groups. Although the difference did not reach statistical significance, mean plasma FSH concentrations recorded in inhibin-immunized heifers remained 35–40% higher than in controls throughout the 12-week period leading up to puberty (P = 0·14) and during nine successive oestrous cycles studied after puberty (P=0·10). Plasma LH concentrations did not differ between groups at any time during the study. Inhibin immunization had no effect on oestrous cycle length (immunized: 19·8±0·5 days; controls: 19·9±0·5 days). However, in comparison with controls, inhibinimmunized heifers had more medium sized (≥0·5 to <1 cm diameter) follicles during both the preovulatory (95%, P<0·001) and post-ovulatory (110%, P < 0·05 waves of follicular growth and more large (>1 cm diameter) follicles during the preovulatory wave (49%, P<0·05). In addition, the number of corpora lutea observed during the post-ovulatory phase of each cycle was significantly greater in the inhibin-immunized group (43%, P<0·01), as was the recorded incidence of cycles with multiple ovulations (19/56 in the inhibin-immunized group compared with 0/54 in controls; P<0·001). All six inhibinimmunized heifers had at least one cycle with multiple ovulation whereas none of the control heifers did so. These results support the conclusion that immunoneutralization of endogenous inhibin using a synthetic peptide-based vaccine can enhance ovarian follicular development and ovulation rate in heifers. Whether this ovarian response is dependent upon the expected increase in secretion of FSH remains to be established. Journal of Endocrinology (1992) 134, 11–18

scholarly journals Survival factors regulating ovarian apoptosis -- dependence on follicle differentiation

Reproduction ◽  
2002 ◽  
pp. 23-30 ◽  
Author(s):  
E Markstrom ◽  
ECh Svensson ◽  
R Shao ◽  
B Svanberg ◽  
H Billig
Keyword(s):  
Growth Factor ◽  
Follicular Development ◽  
Antral Follicle ◽  
Short Review ◽  
Ovarian Follicles ◽  
Survival Factors ◽  
Primordial Follicles ◽  
Survival Factor ◽  
Fetal Ovary

Only a minute fraction of the ovarian follicles present in a fetal ovary will complete the path to ovulation. Most of the follicles will undergo atresia, a hormonally controlled apoptotic process. Apoptosis occurs at each stage of follicular development and there is a marked reduction in the number of follicles present at birth. Stage-dependent mechanisms of follicle survival can be postulated to achieve co-ordinated development, leading to ovulation of a small fraction of follicles. Indeed, hormone and growth factor regulation of follicular atresia is stage-specific. This short review considers the factors that promote survival of ovarian follicles throughout development, including endocrine, locally produced and intracellular mediators, as exemplified mainly by follicular development in rodents. In primordial follicles, oocyte apoptosis is considered to be the cause of subsequent follicle degeneration. In slow-growing preantral follicles, FSH is not a survival factor, but some locally produced growth factors are. Progression to the antral follicle stage is probably the most critical stage of follicle development in vivo, and FSH is a major survival factor at this stage. In addition, insulin-like growth factor I and interleukin 1beta are potent survival factors for cultured rat follicles at the antral stage. Preovulatory follicles express receptors for LH, and both of the gonadotrophins are survival factors at this stage. Relatively little is known about the period between the LH surge and ovulation; however, it has been suggested that at this stage progesterone acts as a survival factor.

121. EXTRACELLULAR ROLES FOR PROREGIONS OF MOUSE BMP15 AND GDF9 IN VIVO

2009 ◽  
Vol 21 (9) ◽  
pp. 40
Author(s):  
C. J. McIntosh ◽  
S. Lawrence ◽  
J. Juengel ◽  
K. McNatty
Keyword(s):  
Mammalian Species ◽  
Follicular Development ◽  
Biologically Active ◽  
Corpora Lutea ◽  
Mature Protein ◽  
Extracellular Secretion ◽  
Morphogenetic Protein ◽  
Signal Region

Bone morphogenetic protein 15 (BMP15) and growth differentiation factor 9 (GDF9) are essential for normal follicular development and ovulation in mammalian species. As TGF-beta family proteins, BMP15 and GDF9 are expressed as pre-pro-mature proteins, with a signal region prompting extracellular secretion, a proregion that is post-translationally cleaved, and a mature protein that is known to be biologically active as a non-covalently interacting dimer. Until recently, the proregion was thought primarily to facilitate correct folding and dimerization of the mature proteins within the oocyte prior to processing and cleavage. However, our in vitro work with recombinant mouse BMP15 and GDF9 has shown that each of the proregion, mature protein and the non-processed promature protein are secreted from transfected 293H cells. We showed non-covalent interactions existing between the proregion and mature protein of each of BMP15 and GDF9, and between the BMP15 proregion and GDF9 mature protein. Importantly, a mouse BMP15 proregion antibody was able to abolish cooperative BMP15 and GDF9 bioactivity measured using a granulosa cell thymidine incorporation bioassay, providing strong evidence for an extracellular role for the mouse BMP15 proregion. Currently, to find out whether BMP15 and GDF9 proregions have extracellular roles in vivo, our investigation has utilised knock-down of BMP15 and GDF9 proregion proteins by mouse immunisation. Ovaries of mice immunised with the GDF9 proregion had significantly increased numbers of corpora lutea (p<0.005), while ovaries from mice immunised with BMP15 proregion peptides had significantly fewer corpora lutea (p<0.005). These findings provide the first evidence that the proregions of mouse GDF9 and BMP15 have different physiological roles outside the oocyte. Our future aim is to elucidate the function of these proregions, how these may differ between BMP15 and GDF9, and whether these aspects differ between species with different ovulation quota.

EFFECTS OF PITUITARY HORMONES ON PROGESTATIONAL HORMONE PRODUCTION BY THE RABBIT OVARY IN VIVO AND IN VITRO

1966 ◽  
Vol 35 (1) ◽  
pp. 53-63 ◽  
Author(s):  
J. H. DORRINGTON ◽  
R. KILPATRICK
Keyword(s):  
Ovarian Tissue ◽  
Venous Blood ◽  
Interstitial Tissue ◽  
Corpora Lutea ◽  
Hormone Production ◽  
Stimulatory Action ◽  
Steroid Synthesis ◽  
Ovine Prolactin

SUMMARY Ovine luteinizing hormone (LH) increased the output of progestational steroids (20α-hydroxypregn-4-en-3-one and progesterone) in rabbit ovarian venous blood. Similar increases were found with ovine follicle-stimulating hormone (FSH) and growth hormone, but much larger amounts were necessary. Ovine prolactin was without effect. The increased output was due to increased synthesis and not only to release of stored steroids. Synthesis of these progestational steroids was stimulated by LH incubated with rabbit ovarian tissue. The stimulation produced by FSH was probably due to contamination by LH since the log dose-response lines for LH and FSH were parallel, and FSH was approximately 100 times less active than LH. Ovine prolactin had no stimulatory activity in concentrations up to 20 μg./ml. The stimulatory action of LH was unrelated to the presence of corpora lutea. Separated corpora lutea showed only a slight response to LH, whereas the response of interstitial tissue was similar to that found with undissected ovaries. Hence LH caused progestational steroid synthesis by stimulating the ovarian interstitial tissue.

scholarly journals Differentiating between the effects of heat stress and lipopolysaccharide on the porcine ovarian heat shock protein response1

2019 ◽  
Vol 97 (12) ◽  
pp. 4965-4973 ◽  
Author(s):  
Jacob T Seibert ◽  
Malavika K Adur ◽  
Ronald B Schultz ◽  
Porsha Q Thomas ◽  
Zoe E Kiefer ◽  
...  
Keyword(s):  
Heat Stress ◽  
Heat Shock ◽  
Luteal Phase ◽  
Animal Health ◽  
Intestinal Barrier ◽  
Follicular Development ◽  
Systemic Circulation ◽  
Corpora Lutea ◽  
Protein Abundance

Abstract Heat stress (HS) negatively affects both human and farm-animal health and undermines efficiency in a variety of economically important agricultural variables, including reproduction. HS impairs the intestinal barrier, allowing for translocation of the resident microflora and endotoxins, such as lipopolysaccharide (LPS), from the gastrointestinal lumen into systemic circulation. While much is known about the cellular function of heat shock proteins (HSPs) in most tissues, the in vivo ovarian HSP response to stressful stimuli remains ill-defined. The purpose of this study was to compare the effects of HS or LPS on ovarian HSP expression in pigs. We hypothesized that ovarian HSPs are responsive to both HS and LPS. Altrenogest (15 mg/d) was administered per os for estrus synchronization (14 d) prior to treatment and three animal paradigms were used: (i) gilts were exposed to cyclical HS (31 ± 1.4 °C) or thermoneutral (TN; 20 ± 0.5 °C) conditions immediately following altrenogest withdrawal for 5 d during follicular development; (ii) gilts were subjected to repeated (4×/d) saline (CON) or LPS (0.1 μg/kg BW) i.v. infusion immediately following altrenogest withdrawal for 5 d; and (iii) gilts were subjected to TN (20 ± 1 °C) or cyclical HS (31 to 35 °C) conditions 2 d post estrus (dpe) until 12 dpe during the luteal phase. While no differences were detected for transcript abundances of the assessed ovarian HSP, the protein abundance of specific HSP was influenced by stressors during the follicular and luteal phases. HS during the follicular phase tended (P &lt; 0.1) to increase ovarian protein abundance of HSP90AA1 and HSPA1A, and increased (P ≤ 0.05) HSF1, HSPD1, and HSPB1 compared with TN controls, while HS decreased HSP90AB1 (P = 0.01). Exposure to LPS increased (P &lt; 0.05) HSP90AA1 and HSPA1A and tended (P &lt; 0.1) to increase HSF1 and HSPB1 compared with CON gilts, while HSP90AB1 and HSPD1 were not affected by LPS. HS during the luteal phase increased (P &lt; 0.05) abundance of HSPB1 in corpora lutea (CL), decreased (P &lt; 0.05) CL HSP90AB1, but did not impact HSF1, HSPD1, HSP90AA1, or HSPA1A abundance. Thus, these data support that HS and LPS similarly regulate expression of specific ovarian HSP, which suggest that HS effects on the ovary are in part mediated by LPS.

scholarly journals In vivo blockade of ovarian sympathetic activity by Neosaxitoxin prevents polycystic ovary in rats

2020 ◽  
Vol 244 (3) ◽  
pp. 523-533
Author(s):  
Miguel del Campo ◽  
Néstor Lagos ◽  
Hernán Lara
Keyword(s):  
Plasma Levels ◽  
Polycystic Ovary ◽  
Follicular Development ◽  
Sympathetic Nerves ◽  
Estradiol Valerate ◽  
Plasma Testosterone ◽  
Corpora Lutea ◽  
Follicular Cyst ◽  
Estrous Cycling

A high sympathetic tone is observed in the development and maintenance of the polycystic ovary (PCO) phenotype in rats. Neosaxitoxin (NeoSTX) specifically blocks neuronal voltage-dependent Na+ channels, and we studied the capacity of NeoSTX administered into the ovary to block sympathetic nerves and PCO phenotype that is induced by estradiol valerate (EV). The toxin was administered with a minipump inserted into the bursal cavity using two protocols: (1) the same day as EV administration and (2) 30 days after EV to block the final step of cyst development and maintenance of the condition. We studied the estrous cycling activity, follicular morphology, steroid plasma levels, and norepinephrine concentration. NeoSTX administered together with EV decreased NA intraovarian levels that were induced by EV, increased the number of corpora lutea, decreased the number of follicular cyst found after EV administration, and decreased the previously increased testosterone plasma levels induced by the PCO phenotype. Estrous cycling activity also recovered. NeoSTX applied after 30 days of EV administration showed near recovery of ovary function, suggesting that there is a specific window in which follicular development could be protected from cystic development. In addition, plasma testosterone levels decreased while those of progesterone increased. Our data strongly suggest that chronic inhibition of sympathetic nerves by a locally applied long-lasting toxin is a new tool to manage the polycystic phenotype in the rat and could be applied to other mammals depending on sympathetic nerve activity.

SIMULTANEOUS INFUSION OF PROSTAGLANDIN E2 ANTAGONIZES THE LUTEOLYTIC ACTION OF PROSTAGLANDIN F2α IN VIVO

1977 ◽  
Vol 72 (3) ◽  
pp. 379-383 ◽  
Author(s):  
K. M. HENDERSON ◽  
R. J. SCARAMUZZI ◽  
D. T. BAIRD
Keyword(s):  
Prostaglandin E2 ◽  
Venous Blood ◽  
Prostaglandin F2α ◽  
Corpora Lutea ◽  
Progesterone Secretion ◽  
Prostaglandin F ◽  
Infusion Period

SUMMARY Corpora lutea of ewes bearing ovarian autotransplants were infused for 4 h with prostaglandin F2α (PGF2α) (10 μg/h), PGF2α + PGE2 (10 μg/h of each), PGE2 (10 μg/h) or saline on day 10 of the cycle. Ovarian venous blood obtained before, during, and up to 12 h after the infusion period, was assayed for progesterone. Prostaglandin F2α produced an immediate, rapid and sustained decline in progesterone secretion, but infusion of PGE2 together with PGF2α prevented the decline until after the infusion. Progesterone secretion was unaffected by infusion of PGE2 alone. Oestrous behaviour was observed in four out of seven animals infused with PGF2α but in only one out of six infused with PGF2α + PGE2. None of the animals infused with PGE2 alone or saline only came into heat.

Inadequate function of corpora lutea following the induction of ovulation with monensin and FSH in seasonally anoestrous ewes

1988 ◽  
Vol 117 (2) ◽  
pp. 167-172 ◽  
Author(s):  
S. Atkinson
Keyword(s):  
Venous Blood ◽  
Plasma Concentrations ◽  
Ovarian Response ◽  
Treated Group ◽  
Luteal Cell ◽  
Control Group ◽  
Corpora Lutea ◽  
Luteal Cells ◽  
The Mean

ABSTRACT Sixteen ewes in mid-seasonal anoestrus were stimulated to ovulate using sequential injections of FSH (total dose 10 mg) over a 4-day period. Half of the ewes received a dietary growth promotant (monensin) known to enhance the ovarian response to exogenous gonadotrophins. The ewes were ovariectomized on day 5 or 11 (day 0 = the initiation of FSH treatment). Serial blood samples were taken in half of the ewes to determine peripheral concentrations of LH and a single sample of ovarian venous blood was collected before ovariectomy. All luteal structures were dissected from the ovaries, counted and incubated in vitro to determine progesterone production. The luteal structures were then examined histologically for the abundance of luteal cells. The physical appearance of the ovary, along with plasma concentrations of LH and ovarian venous oestradiol indicated that the monensin-treated ewes ovulated before control ewes. The corpora lutea from control ewes produced significantly (P <0·05) more progesterone than did the corpora lutea from the monensin-treated group. Furthermore, only 7% of the remaining luteal structures in the monensin-treated group produced significant amounts of progesterone on day 11, whereas 61% of the luteal structures in the control group were actively secreting progesterone. The mean number of granulosa cells in the follicles was similar at ovulation in the two groups, but the mean numbers of large and small luteal cells were significantly (P <0·05) lower in luteal structures from the monensin-treated ewes than in those from the control ewes. It is therefore postulated that inadequate corpora lutea function following precocious ovulation is due to a lack of luteal cell development formed after premature luteinization. J. Endocr. (1988) 117, 167–172

METABOLIC CLEARANCE RATE, PRODUCTION RATE AND MAMMARY UPTAKE OF PROGESTERONE IN THE GOAT

1975 ◽  
Vol 64 (3) ◽  
pp. 485-502 ◽  
Author(s):  
R. B. HEAP ◽  
C. A. BEDFORD ◽  
J. L. LINZELL
Keyword(s):  
Mammary Gland ◽  
Production Rate ◽  
Clearance Rate ◽  
Venous Blood ◽  
Physiological Role ◽  
Mammary Tissue ◽  
Metabolic Clearance ◽  
Metabolic Clearance Rate ◽  
Normal Cycle

SUMMARY The dynamics of progesterone uptake and metabolism in the mammary gland of the goat have been measured and related to the metabolic clearance rate and production rate of the hormone determined by tracer kinetic techniques. The metabolic clearance rate of progesterone from blood was 3·13 ± 0·35 (s.e.m.) 1/min in ten experiments on six goats; values tended to be slightly higher in pregnant than in non-pregnant goats. The production rate of progesterone at oestrus, and at day 3 of the normal cycle, was less than 0·01 μg/min. During the luteal phase of the oestrous cycle the production rate was 8·5 and 14·6 μg/min in 2 animals, and in the second half of pregnancy, 15·3 ± 0·6 μg/min (5 animals). Progesterone was extracted from the circulation by the mammary gland of conscious goats with an efficiency of 49·4 ± 11·3% in non-pregnant, and 51·7 ± 11·5% in pregnant animals. The mean clearance rate of progesterone by the udder was 0·2791/min, 8·8% of the metabolic clearance rate. Mammary uptake of progesterone in goats with an actively secreting corpus luteum was 0·64 ± 0·29μg/min, which gave an estimated value of 0·11– 1·88 ng/min/g mammary gland. The mammary extraction of progesterone was investigated in a goat 3 days after oestrus when any high affinity receptor sites would presumably be unoccupied. During the infusion of progesterone into a mammary artery, tissue samples were taken from various organs, including the mammary gland, and the concentration of labelled compounds at steady state was determined. A high mammary extraction of progesterone was found to be attributable principally to progesterone metabolism. The metabolites of progesterone were removed from the gland in venous blood and were not stored to any appreciable extent in mammary tissue. Experiments in vitro confirmed the findings in vivo that mammary tissue metabolized labelled progesterone and also pregnenolone and androstenedione; metabolism of dehydroepiandrosterone, oestradiol-17β, oestrone and cortisol was relatively small. Confirmation of our previous finding that the mammary gland of the goat can synthesize progesterone from labelled pregnenolone infused into the gland in vivo, further implicates this organ as an active site of metabolism of certain steroids. The physiological role of steroid metabolism in the mammary gland is discussed.

Oxytocin can affect follicular development in the adult mouse

1985 ◽  
Vol 108 (2) ◽  
pp. 273-276 ◽  
Author(s):  
G. Robinson ◽  
J. J. Evans ◽  
M. E. Forster
Keyword(s):  
Adult Mouse ◽  
Follicular Development ◽  
Antral Follicle ◽  
Normal Adult ◽  
Corpora Lutea ◽  
Antral Follicles ◽  
Follicular Maturation ◽  
Ovarian Histology ◽  
Large Numbers ◽  
Experimental Group

Abstract. Injection of oxytocin into normal adult cycling mice caused alterations in ovarian histology. Oxytocin was administered early on the day of pro-oestrus and it induced the appearance of large numbers of corpora lutea by late pro-oestrus, suggesting oxytocin stimulated ovulation. When mice were examined very early on the day of normal oestrus the ovarian population of follicles was different in the experimental group from that in the control mice, there being increased numbers of preantral and antral follicles in treated animals. As oxytocin can cause an alteration in the timing of follicular maturation and ovulation processes study of communications between the adenohypophysis and areas containing oxytocin might be important for understanding physiological details of ovulation. The relative times at which, for instance, antral follicle and corpora lutea populations increased suggested that oxytocin might have more than one activity which affects ovarian behaviour.

Sign in / Sign up

Export Citation Format

Share Document