EFFECT OF EXOGENOUS GROWTH HORMONE DURING THE FOLLICULAR PHASE ON hCG BINDING BY PORCINE LUTEAL TISSUE

1990 ◽  
Vol 70 (2) ◽  
pp. 719-721 ◽  
Author(s):  
R. N. KIRKWOOD ◽  
P. A. THACKER ◽  
B. L. GUEDO ◽  
B. LAARVELD
Keyword(s):  
Growth Hormone ◽  
Key Words ◽  
Ovarian Function ◽  
Binding Capacity ◽  
Follicular Phase ◽  
Corpora Lutea ◽  
Exogenous Growth ◽  
Luteal Tissue

From 14 d after puberty, 37 Yorkshire Landrace gilts received nine daily injections of porcine growth hormone (GH) or vehicle. Gilts were killed 10 d after the onset of their second estrus and their ovaries recovered. Treatment with GH resulted in an increase (P < 0.05) in the hCG binding capacity of the corpora lutea (0.17 vs. 0.11 nmol L−1 mg−1 protein). These data provide a possible mechanism whereby GH may influence ovarian function. Key words: Gilts, hCG binding, growth hormone

THE INFLUENCE OF EXOGENOUS GROWTH HORMONE ON OVULATION RATE IN GILTS

1988 ◽  
Vol 68 (4) ◽  
pp. 1097-1103 ◽  
Author(s):  
R. N. KIRKWOOD ◽  
P. A. THACKER ◽  
A. D. GOONERATNE ◽  
B. L. GUEDO ◽  
B. LAARVELD
Keyword(s):  
Growth Hormone ◽  
Crude Protein ◽  
Ovulation Rate ◽  
Daily Injection ◽  
Corpora Lutea ◽  
Blood Samples ◽  
High Incidence ◽  
Exogenous Growth ◽  
Ad Libitum

A total of 32 prepubertal gilts of Yorkshire and Landrace breeding were selected at 138 d and fed ad libitum a 16.2% crude protein diet formulated to provide 13.1 MJ DE kg−1. From selection until the end of second estrus, the gilts were exposed to a boar for 30 min d−1 to facilitate the detection of pubertal and second estrous periods. From 14 d after puberty, the gilts received daily injections of either porcine growth hormone at 90 μg kg−1 body weight (GH; n = 20) or vehicle (CT; n = 12) until 24 h after the onset of second estrus and were then killed 9 d later to determine ovulation rate. Gilts not displaying a second estrus by 24 day after puberty were considered anestrus and the injection regime was halted. Anestrous gilts were killed 30–32 d after puberty and their ovaries examined for the presence of corpora albicantia and the absence of corpora lutea. Blood samples were obtained from all gilts at 14, 17, and 20 d after puberty. There was no treatment effect on the duration of the estrous cycle (20.8 vs. 21.3 d for GH and CT, respectively), but while all CT gilts cycled normally, only 55% of the GH gilts had a second estrus (P < 0.01). In those gilts having a second estrus, the daily injection of growth hormone increased ovulation rate (14.3 vs. 12.4 for GH and CT respectively; P < 0.03). Serum type 1 insulin-like growth factor (IGF-1) concentrations were higher (P < 0.001) in GH than in CT gilts, but there was no difference between cycling and anestrous GH gilts. We suggest that the effect of growth hormone on ovulation rate was mediated by increased secretion of IGF-1. The etiology of the high incidence of anestrus is, however, not known. Key words: Gilts, growth hormone, ovulation rate

THE INFLUENCE OF EXOGENOUS GROWTH HORMONE ON ENDOCRINE STATUS AND THE OVULATORY RESPONSE TO PMSG IN PREPUBERTAL GILTS

1990 ◽  
Vol 70 (1) ◽  
pp. 309-312 ◽  
Author(s):  
R. N. KIRKWOOD ◽  
P. A. THACKER ◽  
R. S. KORCHINSKI ◽  
B. LAARVELD
Keyword(s):  
Growth Hormone ◽  
Key Words ◽  
Jugular Vein ◽  
Serum Concentrations ◽  
Blood Samples ◽  
Exogenous Growth ◽  
Endocrine Status ◽  
The Difference ◽  
To Receive ◽  
Surge Height

Twenty-three prepubertal Yorkshire × Landrace gilts were allocated to receive daily injections of either porcine growth hormone (pGH) or vehicle for 6 consecutive days. At the time of first pGH or buffer injection, all gilts received an injection of 500 IU PMSG. Blood samples were taken by jugular vein puncture at 0, 24 and 48 h then every 12 h until 96 h then every 8 h until 144 h. Samples were assayed for triiodothyronine (T3), insulin, glucose and LH. Treatment with pGH elevated (P < 0.01) serum concentrations of T3, insulin and glucose, and was associated with a reduced (P < 0.05) LH surge height. Fewer pGH-treated than vehicle-treated gilts ovulated (4/12 vs. 7/11), but the difference was not significant. Key words: Gilts, growth hormone, gonadotrophins, ovulation

THE INFLUENCE OF EXOGENOUS GROWTH HORMONE ON OVULATION RATE IN GILTS FED DIETS WITH DIFFERENT ENERGY AND PROTEIN CONTENTS

1989 ◽  
Vol 69 (1) ◽  
pp. 265-268 ◽  
Author(s):  
R. N. KIRKWOOD ◽  
P. A. THACKER ◽  
B. LAARVELD
Keyword(s):  
Growth Hormone ◽  
Key Words ◽  
Feed Intake ◽  
Dietary Treatment ◽  
High Energy ◽  
Ovulation Rate ◽  
Induced Ovulation ◽  
Exogenous Growth

Following pregnant mare's serum gonadotrophin (PMSG) induced ovulation, 61 Yorkshire × Landrace gilts were allocated to be fed either a control or a high-energy diet for 30 d. From 14 d, gilts on each dietary treatment received nine daily injections of porcine growth hormone or vehicle. Growth hormone depressed feed intake by 30% (P < 0.001), but did not influence ovulation rate. No influence of diet or growth hormone on the incidence of a subsequent ovulation was apparent. Key words: Gilts, diet, growth hormone, ovulation rate

Luteinizing hormone receptors in the bovine corpus luteum during the oestrous cycle and pregnancy

1999 ◽  
Vol 11 (3) ◽  
pp. 147 ◽  
Author(s):  
K. Okuda ◽  
Y. Uenoyama ◽  
C. Naito ◽  
Y. Sakabe ◽  
N. Kawate
Keyword(s):  
Luteinizing Hormone ◽  
Hormone Receptors ◽  
Binding Capacity ◽  
Oestrous Cycle ◽  
Scatchard Analysis ◽  
Corpora Lutea ◽  
Luteal Function ◽  
Significant Difference ◽  
Luteal Tissue ◽  
Three Stages

The concentration and affinity of luteinizing hormone (LH) receptors in bovine luteal tissues during the oestrous cycle and pregnancy were investigated by Scatchard analysis of the binding of 125I-labeled human chorionic gonadotropin. Corpora lutea (CL) were classified into five stages of the oestrous cycle and three stages of pregnancy. The concentration of LH receptors sharply increased from the early I stage of the oestrous cycle (Days 2–3; 3.09 fmol mg-1 protein) to the early II stage (Days 5–6; 9.44 fmol mg-1 protein) and then remained constant until the late luteal stage (Days 15–17; 8.14–9.56 fmol mg-1 protein). The LH receptors could not be analysed in the regressed luteal tissue due to the small amounts of binding. There was no significant difference in the concentrations of LH receptors (5.63–9.64 fmol mg-1 protein) among the three stages of pregnancy. Moreover, the concentrations of the receptors in the CL of pregnancy were comparable to those in the mid-cycle CL. The binding affinity did not change significantly during the oestrous cycle and pregnancy. Based on these results, it is assumed that the luteal function during the entire period of pregnancy might be regulated, at least in part, by LH, which is mediated via its specific receptors, and that the luteal function during pregnancy seems not to be regulated by changes in the binding capacity and affinity of LH receptors. To understand the physiological roles of LH in regulating luteal function in pregnant cows, further studies are required.

DISTRIBUTION OF OESTRONE AND OESTRADIOL-17β IN SOW OVARIES

1963 ◽  
Vol 44 (4) ◽  
pp. 529-535 ◽  
Author(s):  
Torleiv Lunaas
Keyword(s):  
Follicular Fluid ◽  
Luteal Phase ◽  
Follicular Phase ◽  
Oestrous Cycle ◽  
Corpora Lutea ◽  
Luteal Tissue ◽  
Low Levels ◽  
The Absolute ◽  
Residual Tissue ◽  
Highly Correlated

ABSTRACT The contents of oestrone and oestradiol-17β were estimated in component parts of sow ovaries representative of the follicular and luteal phase of the oestrous cycle and also in whole juvenile ovaries. The values obtained of the sum total oestrone and oestradiol-17β in the follicular fluid and in the corresponding residual tissue were highly correlated. The proportions of oestradiol-17β tended to be larger in the follicular fluid than in the tissue (mean percentage: 84.3 and 69.6 respectively). In ovaries from the luteal phase of the oestrous cycle the oestrogen levels were generally lower than in ovaries from the follicular phase. Whereas no difference was found between the very low levels of oestrone in the corpora lutea and in the remainder of the ovary containing small follicles, the levels of oestradiol-17β differed significantly, being lower in the luteal tissue. Within each category of ovaries the absolute levels of the oestrogens were very variable. The results are discussed in relation to the pattern of urinary oestrone excretion in the sow during the oestrous cycle.

THE INFLUENCE OF GONADOTROPHIN-RELEASING HORMONE AT ESTRUS ON OVULATION RATE AND THE DEVELOPMENT OF CORPORA LUTEA IN EWES

1990 ◽  
Vol 70 (3) ◽  
pp. 983-985 ◽  
Author(s):  
R. N. KIRKWOOD ◽  
P. A. THACKER ◽  
L. M. RUTTER ◽  
F. X. AHERNE
Keyword(s):  
Key Words ◽  
Binding Capacity ◽  
Ovulation Rate ◽  
Corpora Lutea ◽  
Blood Samples ◽  
Releasing Hormone ◽  
Gonadotrophin Releasing Hormone

Twenty-two ewes received either 30 μg GnRH or saline at the onset of estrus. Blood samples were obtained on days 1–7 (day 0 = estrus) and corpora lutea recovered surgically at day 7. There was no effect of GnRH on the number or weight of corpora lutea nor on the concentrations of progesterone in either corpora lutea or plasma. GnRH treatment caused an increase (P < 0.07) in luteal hCG binding capacity (0.66 ± 0.12 vs. 0.34 ± 0.12 nmol mg−1 protein). Key words: GnRH, estrus, corpora lutea, hCG binding

Localization of oxytocin and neurophysin in baboon (Papio anubis) corpus luteum by immunocytochemistry

1986 ◽  
Vol 113 (4) ◽  
pp. 570-575 ◽  
Author(s):  
Firyal S. Khan-Dawood
Keyword(s):  
Corpus Luteum ◽  
Rabbit Serum ◽  
Corpora Lutea ◽  
Positive Staining ◽  
Normal Rabbit Serum ◽  
Fallopian Tubes ◽  
Papio Anubis ◽  
Luteal Cells ◽  
Luteal Tissue ◽  
Immunocytochemical Reaction

Abstract. Immunoreactive oxytocin is detectable in the corpora lutea of women and cynomolgus monkeys by radioimmunoassay. To localize the presence of oxytocin and neurophysin I in ovarian tissues of subhuman primates, three corpora lutea and ovarian stromal tissues and two Fallopian tubes obtained during the menstrual cycle of the baboon and decidua from two pregnant baboons were examined using highly specific antisera against either oxytocin or neurophysin I and preoxidase-antiperoxidase light microscopy immunohistochemistry. Oxytocin-like as well as neurophysin I-like immunoreactivities were found in some cells of all the corpora lutea only, but could not be demonstrated in ovarian stromal tissues, Fallopian tubes and decidua. Specificity of the immunocytochemical reaction was further confirmed by immunoabsorption of the antiserum with excess oxytocin or neurophysin, after which the immunoreactivities for both oxytocin and neurophysin in the luteal tissue were negative. Similar controls using normal rabbit serum gave no positive staining for either oxytocin or neurophysin. Counterstaining of the positive immunoreactivities for oxytocin and neurophysin I with Mayer's haematoxylin and eosin demonstrated clearly that the oxytocin and neurophysin I appeared as granular material mainly within the cytoplasm of the luteal cells. The localization of immunoreactive oxytocin and neurophysin I in the corpus luteum of the baboon demonstrates directly the presence of these two neurohypophysial peptides within primate luteal cells and suggests their local production.

DETERMINATION OF AFTER-RIPENING PERIOD AND HORMONAL RESPONSE OF OROBANCHE SOLMSII C.D. CLARKE SEEDS

1970 ◽  
Vol 11 (1) ◽  
Author(s):  
A. Bista ◽  
G. B. Khattri ◽  
B. D. Acharya ◽  
S. C. Srivastava
Keyword(s):  
Growth Hormone ◽  
Seed Germination ◽  
Key Words ◽  
Incubation Period ◽  
Seed Set ◽  
Summer Season ◽  
Conditioning Period ◽  
Root Parasite ◽  
One Year

To find out the ability of Orobanche seeds to germinate immediately after seed set, seeds were germinated periodically at an interval of three months for one year in GR24. Some Orobanche seeds were capable of germination immediately after seed set but most required about nine months as after ripening or incubation period to be able to germinate. The phenomenon of after ripening in Orobanche seeds could be taken as an ecological measure to dormant over following unfavorable wet summer season. The growth hormone studies on Orobanche seed germination have shown that GA3 at a concentration of 100 ppm substantially enhanced seed germination when applied during pre-conditioning period. NAA showed some stimulatory effect at 0.5 - 1.0 ppm when applied during post-conditioning period but the hormone if applied during pre-conditioning period inhibited the germination. Kinetin failed to stimulate the germination at all the concentrations tested. Key words: Germination, root-parasite, hormone. Ecoprint Vol.11(1) 2004.

scholarly journals A rodent model of human dose-equivalent progestin-only implantable contraception

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Heather C. M. Allaway ◽  
Roger A. Pierson ◽  
Jesse Invik ◽  
Susan A. Bloomfield
Keyword(s):  
Repeated Measures ◽  
Ovarian Function ◽  
Virgin Female ◽  
Rodent Model ◽  
High Dose ◽  
Corpora Lutea ◽  
Average Dose ◽  
Estrus Cycle ◽  
Human Dose ◽  
Dose Dependent

Abstract Background Long-acting, reversible contraceptives (LARC; progestin only) are an increasingly common hormonal contraceptive choice in reproductive aged women looking to suppress ovarian function and menstrual cyclicity. The overall objective was to develop and validate a rodent model of implanted etonogestrel (ENG) LARC, at body size equivalent doses to the average dose received by women during each of the first 3 years of ENG subdermal rod LARC use. Methods Intact, virgin, female Sprague-Dawley rats (16-wk-old) were randomized to 1 of 4 groups (n = 8/group) of ENG LARC (high-0.30μg/d, medium-0.17μg/d, low-0.09μg/d, placebo-0.00μg/d) via a slow-release pellet implanted subcutaneously. Animals were monitored for 21 days before and 29 days following pellet implantation using vaginal smears, ultrasound biomicroscopy (UBM), saphenous blood draws, food consumption, and body weights. Data were analyzed by chi-square, non-parametric, univariate, and repeated measures 2-way ANOVA. Results Prior to pellet implantation there was no difference in time spent in estrus cycle phases among the treatment groups (p > 0.30). Following pellet implantation there was a dose-dependent impact on the time spent in diestrus and estrus (p < 0.05), with the high dose group spending more days in diestrus and fewer days in estrus. Prior to pellet insertion there was not an association between treatment group and estrus cycle classification (p = 0.57) but following pellet implantation there was a dose-dependent association with cycle classification (p < 0.02). Measurements from the UBM (ovarian volume, follicle count, corpora lutea count) indicate an alteration of ovarian function following pellet implantation. Conclusion Assessment of estrus cyclicity indicated a dose-response relationship in the shift to a larger number of acyclic rats and longer in duration spent in the diestrus phase. Therefore, each dose in this model mimics some of the changes observed in the ovaries of women using ENG LARC and provides an opportunity for investigating the impacts on non-reproductive tissues in the future.

The interrelationship between and the regulation of hepatic growth hormone receptors and circulating GH binding protein in the pig

1992 ◽  
Vol 126 (2) ◽  
pp. 155-161 ◽  
Author(s):  
Geoffrey R Ambler ◽  
Bernhard H Breier ◽  
Andrzej Surus ◽  
Hugh T Blair ◽  
Stuart N McCutcheon ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Growth Hormone Receptor ◽  
Hormone Receptors ◽  
Binding Capacity ◽  
Binding Protein ◽  
Somatic Growth ◽  
Gh Receptor ◽  
Age Related ◽  
Igf I ◽  
Serum Gh

We evaluated the interrelationship between, and regulation of, the hepatic growth hormone receptor and serum GH binding protein (GH BP) in pigs treated with recombinant porcine growth hormone (rpGH). Infant and pubertal male pigs (N = 5 per group) received either rpGH 0.15 mg/kg daily or diluent intramuscularly for 12 days. Somatic growth, serum IGF-I and GH BP and [125I]bovine GH (bGH) binding to MgCl2-treated hepatic membrane homogenates were examined. Marked age-related increases were seen in serum GH BP (p<0.001) and [125I]bGH binding to hepatic membranes (p<0.001). GH BP was increased in rpGH treated animals (p = 0.03), from 13.8±1.2 (mean±1 x sem) (controls) to 17.8±2.0% in infants, and from 35.2±2.6 (controls) to 41.8±3.4% in pubertal animals. [125I]bGH binding to hepatic membranes was also increased by rpGH treatment (p<0.05), from 7.0±1.6 (controls) to 15.4±3.6% in infants and from 53.7±7.1 (controls) to 65.1±11.8% in pubertal animals. No significant interaction between age and treatment was seen. Overall, serum GH BP correlated significantly with [125I]bGH membrane capacity (r=0.82, p<0.001), with a correlation of r= 0.83 in the infant animals but no significant correlation in the pubertal animals considered alone (r=0.13). Serum IGF-I correlated significantly with serum GH BP (r=0.93, p<0.001) and [125]bGH membrane binding capacity (r = 0.91, p< 0.001). These observations suggest that serum GH BP levels reflect major changes of hepatic GH receptor status. In addition, the present study demonstrates that the hepatic GH receptor can be induced by GH in the infant pig, despite a developmentally low GH receptor population at this age, suggesting potential efficacy of GH at earlier ages than generally considered.

Sign in / Sign up

Export Citation Format

Share Document