ESTROGEN-INDUCED LH AND FSH RELEASE IN OVARIECTOMIZED EWES: EFFECT OF SEASON

1978 ◽  
Vol 58 (4) ◽  
pp. 547-551 ◽  
Author(s):  
B. E. HOWLAND ◽  
D. B. BEATON ◽  
L. M. SANFORD ◽  
W. M. PALMER
Keyword(s):  
Breeding Season ◽  
Estrogen Treatment ◽  
Serum Samples ◽  
Serum Lh ◽  
Estradiol 17Β

Five ovariectomized ewes were each injected i.m. with 50μg estradiol-17β in oil at 1800 h on 9 June, 19 July, 2 Sept. and 20 Oct. Serum samples of jugular blood, collected at 1-h intervals from 12 or 13 h to 30 h after estrogen treatment were assayed for LH and FSH. With the exception of one ewe in July, estrogen consistently induced a rise in serum LH. A rise in serum FSH accompanied the LH rise in only two of the five animals. The interval between estrogen injection and peak gonadotropin levels decreased (P < 0.05) between July and October but no difference was observed in either the peak gonadotropin levels or amount of LH released. The data suggest that estrogen-treated ovariectomized ewes do not respond consistently with a release of both LH and FSH and that the transition from anestrous to the breeding season is associated with a slightly shorter interval between estrogen injection and peak gonadotropin levels.

CHANGES IN HYDROLASE ENZYMORPHOLOGY OF RAT UTERUS AND VAGINA AFTER ESTROGENS; NAPHTHOL AS SUBSTRATES

1964 ◽  
Vol 12 (12) ◽  
pp. 908-918 ◽  
Author(s):  
KEIICHI WATANABE ◽  
WILLIAM H. FISHMAN
Keyword(s):  
Alkaline Phosphatase ◽  
Acid Phosphatase ◽  
Enzyme Hydrolysis ◽  
Estrogen Treatment ◽  
Capillary Endothelium ◽  
Nonspecific Esterase ◽  
Rat Uterus ◽  
New Findings ◽  
Estradiol 17Β ◽  
Estrogen Administration

The early enzymorphologic changes of rat uterus and vagina on castration and following estrogen administration (estradiol-17β, estrone and estriol) were examined with regard to alkaline phosphatase, esterase, β-glucuronidase and acid phosphatase using naphthol AS compounds as substrates. Castration caused a marked decrease of enzyme activities except for alkaline phosphatase of capillary endothelium and for nonspecific esterase. All activities, compared to castrated controls, were markedly increased by estrogen administration except for the alkaline phosphatase of capillary endothelia. Estriol and estrone were more potent than estradiol-17β in the early stage of estrogen treatment (4-hour interval). The response of alkaline phosphatase of striated border of lumenal uterine epithelium to estrogen treatment is unique in that the other hydrolases were absent from this site. The estrogen sensitivity of the hydrolases of connective tissue cells of rat uterine stroma is clearly evident for the first time. Of interest also is a comparison of β-glucuronidase and acid phosphatase in which naphthol AS-BI is the product of enzyme hydrolysis in each case. Although the intensity of the respective staining reactions correlated well with each other in relation to the events of castration and estrogen administration, there were clear differences evident. Finally, the new findings demonstrate the value of the improved techniques as well as resolve some ambiguities of earlier findings obtained with diverse methods.

Can the transition into anoestrus in the ewe be accounted for solely by insufficient tonic LH secretion?

1985 ◽  
Vol 106 (1) ◽  
pp. 55-60 ◽  
Author(s):  
S. J. Legan ◽  
R. L. Goodman ◽  
K. D. Ryan ◽  
D. L. Foster ◽  
F. J. Karsch
Keyword(s):  
Corpus Luteum ◽  
Breeding Season ◽  
Negative Feedback ◽  
Ovarian Response ◽  
Ovulatory Cycle ◽  
Serum Lh ◽  
Transient Rise ◽  
Lh Secretion ◽  
Sustained Increase

ABSTRACT It has been proposed that a seasonal increase in oestradiol negative feedback elicits anoestrus by preventing a key step in the preovulatory sequence of endocrine events, namely a sustained increase in tonic LH secretion. In the present study we compared the patterns of serum LH, FSH, oestradiol and progesterone after regression of the last corpus luteum of the breeding season, with their respective patterns during an ovulatory cycle in the late breeding season (samples obtained every 4 h from eight ewes). After regression of the last corpus luteum of the breeding season, serum LH and oestradiol showed distinct deviations from their respective late breeding season patterns. The rise in tonic LH secretion was curtailed. Further, there were no marked increases in oestradiol, despite a distinct, although brief, tonic LH rise; thus there were no gonadotrophin surges. If the hypothesis that the transition into anoestrus is caused solely by insufficient tonic LH secretion were correct, the brief increase in LH should have induced a transient rise in oestradiol. Since this was not the case, these results suggest that a decreased ovarian response to LH may also contribute to the termination of oestrous cyclicity at the transition to anoestrus. J. Endocr. (1985) 106, 55–60

INFLUENCE OF SEXUAL ACTIVITY ON SERUM LEVELS OF LH AND TESTOSTERONE IN THE RAM

1974 ◽  
Vol 54 (4) ◽  
pp. 579-585 ◽  
Author(s):  
L. M. SANFORD ◽  
W. M. PALMER ◽  
B. E. HOWLAND
Keyword(s):  
Sexual Activity ◽  
Sampling Period ◽  
Serum Levels ◽  
Serum Samples ◽  
Sexual Stimulation ◽  
Consistent Relationship ◽  
Serum Lh ◽  
Serum Peak ◽  
Second Period ◽  
Observation Period

Two experiments were conducted in January to study the influence of various types of sexual activity on serum levels of LH and testosterone (T) in the ram. Serum LH and T were determined by radioimmunoassay, LH values being expressed in terms of ng NIH-LH-S14/ml. In the first experiment, seven Finnish Landrace rams, 11 mo to 3 yr of age, were allowed individually to mate once (day 1) and continuously mount without intromission for 2 min (day 2) an estrual ewe. Jugular blood (6 ml) was collected by venipuncture at 20-min intervals for at least 2 h prior to and following each type of sexual activity. Two hours following mounting activity on day 2, estrual ewes were walked in front of the rams for 5 min. Blood was collected from each ram at 10 and 30 min following this observation period. Several serum peaks (4–8) of LH occurred in all rams over the two sampling periods (9 h). Although a rise in LH followed one or more of the types of sexual stimulation in four of the seven rams, no consistent relationship was noted between sexual stimulation and LH peaks. In a second experiment, serum samples were obtained every 20 min for two separate 24-h periods, 1 wk apart, from two 3-yr-old Finnish Landrace rams. During the first 24-h period, the rams were penned individually; during the second period each was penned with an estrual ewe. Numerous matings (44 and 24) were recorded for the rams during the latter period, 74% of which took place during the first 12 h. The serum profiles of LH and T during the first 24-h period were characterized by periodic peaks of LH associated with similar changes in T. These profiles appeared to be influenced markedly by sexual activity during the second 24-h period. Higher baseline and mean serum levels of both hormones and a greater number of serum peaks of LH and T were observed during the first 12 h. The serum levels of both hormones then decreased sharply at 13–14 h and remained low for 8–10 h, even though mating occurred periodically during this time. Subsequently, a further serum peak of LH and T was observed before the end of the sampling period.

scholarly journals Effect of different dosages of PG-600 on ovulation and pregnancy rates in ewes during the breeding season

2018 ◽  
Vol 3 (1) ◽  
pp. 429-432 ◽  
Author(s):  
Hayder Mohammed Hassan Habeeb ◽  
Timothy M Hazzard ◽  
Fred Stormshak ◽  
Michelle A Kutzler
Keyword(s):  
Pregnancy Rate ◽  
Breeding Season ◽  
Chorionic Gonadotropin ◽  
Repeated Measures ◽  
Animal Health ◽  
Pregnancy Rates ◽  
Analysis Of Covariance ◽  
Future Research ◽  
Nonbreeding Season ◽  
Estradiol 17Β

Abstract This study compared the reproductive effects of different dosages of PG-600 (Intervet/Merck Animal Health, Madison, NJ) during the breeding season of ewes. PG-600 is a single-dose injectable product labeled for estrous induction in swine, containing equine chorionic gonadotropin (80 IU/mL) and human chorionic gonadotropin (40 IU/mL). PG-600 is routinely used off-label for out-of-season estrous induction in sheep. However, at the most common dose administered to ewes (5 mL), PG-600 is likely to overstimulate the ovaries, resulting in reduced pregnancy rates. Following estrous synchronization with intravaginal progesterone and cloprostenol, Polypay ewes were treated with 5 mL PG-600 (T1; n = 8), 1.5 mL PG-600 (T2; n = 8), or 5 mL saline (C; n = 8) and then mated to rams. Jugular vein samples were collected prior to the PG-600 injection (0 hr) and at 2, 4, 8, 12, and 24 hr after injection. Serum estradiol-17β was determined by chemiluminescence and among groups using repeated measures analysis of covariance. Ovulation and pregnancy rates were determined by transrectal ultrasonography and compared by one-way ANOVA and chi-square, respectively. Estradiol-17β concentrations were greater in T1 compared to T2 and C (P &lt; 0.001). Ovulation rate was greater (P &lt; 0.001) but pregnancy rate was lower (P &lt; 0.001) in the T1 compared to C and T2. These data confirm that a 5 mL dose of PG-600 administered to ewes during the breeding season overstimulates the ovaries, which may then reduce fertilization or embryo survival. Future research will focus on the effects of different dosages of PG-600 on pregnancy rate of ewes during the nonbreeding season.

scholarly journals Diurnal Rhythms of Luteinizing Hormone, Follicle-Stimulating Hormone, and Testosterone Secretion before the Onset of Male Puberty1

1999 ◽  
Vol 84 (1) ◽  
pp. 29-37
Author(s):  
Ryo Mitamura ◽  
Koichi Yano ◽  
Naoki Suzuki ◽  
Yoshiya Ito ◽  
Yoshio Makita ◽  
...  
Keyword(s):  
Time Series ◽  
High Sensitivity ◽  
Serum Testosterone ◽  
Lag Time ◽  
Early Morning ◽  
Diurnal Rhythms ◽  
Serum Samples ◽  
Hormonal Change ◽  
Testosterone Concentration ◽  
Serum Lh

To investigate hormonal change before the onset of male puberty, we measured LH and FSH in serum samples drawn every 20 min for 24 h and measured testosterone hourly for 24 h. Forty-six boys (32 prepubertal and 14 pubertal) of short stature, between 4.4–19.3 yr of age, participated in this study. LH and FSH were measured using a time-resolved immunofluorometric assay, and testosterone was measured using high sensitivity RIA capable of detecting a testosterone concentration of 0.01 ng/mL. Diurnal rhythms of LH, FSH, and testosterone were apparent in all subjects, including those aged 4–5 yr. Serum LH and FSH concentrations showed night-day variation in a pulsatile fashion. The serum testosterone concentration was elevated at early morning in all subjects. Mean 24-h LH, FSH, and testosterone concentrations of prepubertal subjects who did not attain puberty for at least 3 yr were 0.10 U/L, 0.63 U/L, and 0.06 ng/mL, respectively, whereas those of prepubertal subjects who attained puberty within 1 yr (0.54 U/L, 1.68 U/L, and 0.10 ng/mL, respectively) were significantly higher. Furthermore, mean 24-h LH, FSH, and testosterone concentrations increased with developing puberty. All of the 46 subjects showed positive cross-correlation between the LH and testosterone time series. The mean lag time from the LH to the testosterone time series in the prepubertal subjects who attained puberty within 1 yr (4.7 ± 2.4 h, mean ± sd) was shorter than that in the prepubertal subjects who attained puberty after at least 3 yr (7.3± 2.2 h). This lag time decreased with developing puberty, plateauing at 1.4 ± 0.9 h at midpuberty. Thus, the diurnal rhythms of LH, FSH, and testosterone already exist at 4–5 yr of age; serum LH, FSH, and testosterone levels increase before the onset of puberty; and a time delay is observed between the LH and testosterone time series that decreases before the onset of puberty.

scholarly journals SAT-043 Utility of Ultrasensitive Inhibin B Measurement for the Management of Men with Non-Obstructive Azoospermia

2020 ◽  
Vol 4 (Supplement_1) ◽  
Author(s):  
Anne-Laure Barbotin ◽  
Ajay Kumar ◽  
Bhanu Kalra ◽  
Gopal Savjani ◽  
Valarie Mitchell ◽  
...  
Keyword(s):  
Activin A ◽  
Inhibin B ◽  
University Hospital ◽  
Testicular Sperm Extraction ◽  
Obstructive Azoospermia ◽  
Serum Samples ◽  
Inhibin A ◽  
Testosterone Levels ◽  
Medical Centers ◽  
Serum Lh

Abstract Inhibin B measurement by conventional assay(s) may be useful in the assessment of spermatogenesis in infertile male patients, especially in cases of azoospermia. Indeed, numerous previous studies have shown that Inhibin B could be helpful to predict a positive testicular sperm extraction (TESE). However, an undetectable Inhibin B concentration (&lt;10pg/mL) does not predict a TESE failure in all cases. These findings explained that most medical centers have precluded the use of Inhibin B assay in the pre-operative hormonal assessment of azoospermic men. Recently, an ultrasensitive Inhibin B assay has been developed allowing the measurement of concentrations below 10pg/mL. The current study aims to assess the clinical relevance of this new assay in men with azoospermia with undetectable Inhibin B levels by conventional assay(s). Methods: This retrospective study included 71 non-obstructive azoospermic men who had undetectable Inhibin B levels (i.e. &lt;10pg/mL by Gen II ELISA from Beckman Coulter, USA) and who underwent a TESE procedure between 2013 and 2019 in the Lille University Hospital. Serum LH, FSH and testosterone levels were systematically measured by routine immunoassays. Cryopreserved serum samples were used to perform ultrasensitive Inhibin B assay (Ultrasensitive Inhibin B, AL-195, Ansh Labs, USA). Additional hormonal assays including Inhibin A, Activin B and Activin A were performed on available subset of samples. Results: The TESE was successful, allowing sperm cryopreservation in 32.5 % (25/71) of the cases. No significant statistical difference was found in FSH, LH, or testosterone levels between patients with positive or negative TESE. By contrast, men with positive TESE had more than twice higher serum ultrasensitive Inhibin B levels (median 5.03pg/mL [1.93-8.5] vs. 2.19pg/mL [0.2-4.72], p=0.006). An ultrasensitive Inhibin B serum level &gt;3.67 pg/mL (determined by ROC analysis) was associated with increased odds ratio (OR= 4.82; 95% CI: 1.647-12.93) for positive TESE. Inhibin A, Activin B and Activin A serum concentrations did not differ significantly between the two groups. Conclusion: FSH measurement which is routinely performed in men with azoospermia was not predictive of successful TESE whereas, Inhibin B was found to be a valuable marker in predicting TESE success in this population using ultrasensitive Inhibin B assay.

APPLICATION OF A RADIOLIGAND RECEPTOR ASSAY FOR DETERMINATION OF LUTEINIZING HORMONE IN HUMAN SERUM

1976 ◽  
Vol 81 (1) ◽  
pp. 54-72 ◽  
Author(s):  
F. A. Leidenberger ◽  
R. Willaschek ◽  
V. G. Pahnke ◽  
L. E. Reichert
Keyword(s):  
Human Serum ◽  
Precipitation Method ◽  
Serum Samples ◽  
Serum Lh ◽  
Fractionation Procedure ◽  
Receptor Assay ◽  
Menopausal Women ◽  
Post Menopausal ◽  
Radioligand Receptor Assay ◽  
Lh Releasing Hormone

ABSTRACT A sensitive, specific and economic radioligand receptor assay is described for measurement of LH in human serum (RRA-LH). By means of ethanol fractionation or (NH4)2SO4-precipitation serum can be prepared for LH-quantitation and tested in the RRA-LH without interference of a nonspecific inhibiting substance present in untreated serum from various human sources. Treatment of serum with 8 % ethanol separates nonspecific inhibiting substances from LH, the latter remaining in the supernatant at this ethanol concentration. The criteria of specificity are examined. The results of experiments designed to produce evidence for or against specificity suggest specificity of the RRA-LH. Recoveries, as estimated by administration of [125I]hLH and unlabelled hLH to untreated serum samples are shown to be between 80 and 95 % for the ethanol fractionation procedure and between 65 and 75 % for the (NH4)2SO4-precipitation method. The ethanol fractionation procedure is preferred for routine serum-LH determination because of its simplicity, speed and higher recoveries. Ethanol-treated sera from post-menopausal women show, on average, higher RRA-LH concentrations than ethanol-treated sera from young women. RRA-LH values are consistently higher than LH-values found by radioimmunoassay (RIA-LH). The LH-concentrations in sera from two menstrual cycles and from two LH-releasing hormone tests are measured by RRA-LH and by RIA-LH. Similarities and discrepancies of the LH-profiles found by the two assay systems are described.

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