PHOTOPERIOD-INDUCED CHANGES IN LH, FSH, PROLACTIN AND TESTOSTERONE SECRETION IN THE RAM

1978 ◽  
Vol 58 (2) ◽  
pp. 123-128 ◽  
Author(s):  
LEE M. SANFORD ◽  
W. MARTYN PALMER ◽  
D. BRUCE BEATON ◽  
BORDEN E. HOWLAND
Keyword(s):  
Luteinizing Hormone ◽  
Venous Blood ◽  
Follicle Stimulating Hormone ◽  
Peak Height ◽  
Testosterone Concentration ◽  
Testosterone Secretion ◽  
Serum Lh ◽  
Reproductive Endocrine ◽  
Induced Changes ◽  
Stimulating Hormone

Two "annual" reproductive–endocrine cycles were produced in rams during a 12-mo period by photoperiodic manipulation. Two Finnish Landrace rams were housed in a "light-proof" room between 21 Dec. 1974 and 21 June 1976; they were exposed to three consecutive photoperiod cycles in which the sinusoidal fluctuation in the annual daylight rhythm characteristic of Southern Manitoba was reproduced in 6 mo. Daylength started to decline on the 21st day of December and June. Light-controlled rams and two rams penned outside (controls) were bled at 3- to 5-wk intervals between mid-June 1975 and mid-June 1976. Jugular venous blood was collected at 20-min intervals for 8 h on each occasion. Sera were assayed for luteinizing hormone (LH), follicle stimulating hormone (FSH), prolactin (PRL) and testosterone. The onset of decreasing daylength was followed by increases in serum FSH and testosterone concentrations and a decrease in PRL concentration in both pairs of rams. However, photoperiod-related changes in serum LH concentration in rams were not comparable during 6- and 12-mo "annual" photoperiod cycles. In all rams, periods of elevated testosterone concentration were characterized by increases in LH- and testosterone-peak frequencies and testosterone-peak height, and a decrease in LH-peak height.

CHANGES IN SERUM LEVELS OF FOLLICLE STIMULATING HORMONE AND LUTEINIZING HORMONE SHORTLY BEFORE AND AFTER PARTURITION IN RATS

1974 ◽  
Vol 75 (3) ◽  
pp. 491-496 ◽  
Author(s):  
Junichi Mori ◽  
Hiroshi Nagasawa ◽  
Reiko Yanai ◽  
Junji Masaki
Keyword(s):  
Luteinizing Hormone ◽  
Follicle Stimulating Hormone ◽  
Serum Levels ◽  
Sprague Dawley ◽  
Appreciable Change ◽  
Serum Lh ◽  
Sprague Dawley Rats ◽  
Before And After ◽  
Average Serum ◽  
Stimulating Hormone

ABSTRACT The sequence of changes in the serum levels of follicle stimulating hormone (FSH) and luteinizing hormone (LH) from 2 days before to 24 h after parturition of primiparous Sprague-Dawley rats was investigated by radioimmunoassay. No appreciable change in average serum FSH levels was observed during 2 days before and 1 h after parturition. After this the levels increased gradually to show a peak at 7 h after parturition and then declined gradually until 24 h after parturition. However, the level at 24 h after parturition was still twice as high as that at parturition (0 h). The average serum LH levels which were low between 2 days before and 1 h after parturition, showed a peak at 7 h and decreased toward 13 h after parturition. The same levels as at parturition were maintained between 13 and 24 h after parturition. The time of surge of either FSH or LH was closely related to the time after parturition. There were some differences between FSH and LH in the patterns of sequence of changes in the serum levels near parturition.

EFFECT OF SYNTHETIC LUTEINIZING HORMONE-AND FOLLICLE STIMULATING HORMONE-RELEASING HORMONE (LH/FSH-RH) ON SERUM LEVELS OF LH, FSH, THYROTROPHIN (TSH) AND GROWTH HORMONE (HGH) IN NORMAL MALE SUBJECTS

1973 ◽  
Vol 73 (3) ◽  
pp. 465-474 ◽  
Author(s):  
Egil Haug ◽  
Peter Torjesen
Keyword(s):  
Growth Hormone ◽  
Luteinizing Hormone ◽  
Follicle Stimulating Hormone ◽  
Normal Male ◽  
Serum Growth Hormone ◽  
Maximum Serum ◽  
Releasing Hormone ◽  
Serum Lh ◽  
Male Subjects ◽  
Stimulating Hormone

ABSTRACT Four normal male subjects received iv injections of synthetic luteinizing hormone- and follicle stimulating hormone-releasing hormone (LH/FSH-RH) in doses of 12.5, 25, 100, 200 and 400 μg, respectively. A dose of 12.5 μg of LH/FSH-RH caused a significant increase in serum FSH, and 25 μg significantly increased the serum LH. The peak responses occurred 15 to 30 min after the LH/FSH-RH injections in most of the experiments. The increase in the mean maximum serum LH and FSH levels was 2 to 4 fold. There was great variation in response between the subjects, but when tested repeatedly with the same dose of LH/FSH-RH a given individual responded in a consistent manner. The log dose-response curve between LH/FSH-RH and serum LH, and between LH/FSH-RH and serum FSH was approximately linear. A small but significant (P < 0.05) rise in serum thyrotrophin (TSH) was found after LH/FSH-RH in doses ranging from 25 to 400 μg. There was no significant rise in serum growth hormone (HGH). On the basis of the present study a standard 100 μg iv LH/FSH-RH test is suggested.

Inhibition of luteinizing hormone, follicle-stimulating hormone and sex-steroid levels in men and women with a potent antagonist analog of luteinizing hormone-releasing hormone, Cetrorelix (SB-75)

1994 ◽  
Vol 131 (3) ◽  
pp. 286-292 ◽  
Author(s):  
David Gonzalez-Barcena ◽  
Manuel Vadillo Buenfil ◽  
Emilo Garcia Procel ◽  
Laura Guerra-Arguero ◽  
Imelda Cardenas Cornejo ◽  
...  
Keyword(s):  
Luteinizing Hormone ◽  
Follicle Stimulating Hormone ◽  
Free Testosterone ◽  
Serum Levels ◽  
Routes Of Administration ◽  
Serum Lh ◽  
The Mean ◽  
Potent Antagonist ◽  
Normal Men ◽  
Stimulating Hormone

Gonzalez-Barcena D, Vadillo Buenfil M, Garcia Procel E, Guerra-Arguero L, Cardenas Cornejo I, Comaru-Schally AM, Schally AV. Inhibition of luteinizing hormone, follicle-stimulating hormone and sex-steroid levels in men and women with a potent antagonist analog of LH-RH, Cetrorelix (SB-75). Eur J Endocrinol 1994;131:286–92. ISSN 0804–4643 Cetrorelix (SB-75; [Ac-d-Nal(2)1, d-Phe(4Cl)2, d-Pal(3)3, d-Cit6, d-Ala10] luteinizing hormone-releasing hormone (LHRH)) is a new highly potent antagonist analog of LHRH containing the d-ureidoalkyl amino acid d-citrulline at position 6 and is free of allergenic effects. This study shows the inhibition of LH and follicle-stimulating hormone (FSH) release in normal men, postmenopausal women and patients with gonadal dysgenesis, using different doses and im, sc and iv routes of administration of SB-75. The mean serum levels of LH and FSH in normal men who received one single dose of 300 μg of SB-75 sc started to decline rapidly 1 h after its administration; the LH suppression was sustained for 14 h and that of FSH up to 24 h or longer as the samples were obtained only up to this time. The nadir for LH was reached at 14 h and that for FSH at 24 h or later after administration of the antagonist (p < 0.05). Serum levels of total and free testosterone decreased after the first hour and this inhibition was maintained for up to 14 h. The nadir for total testosterone was at 6 h and that for free testosterone was at 8 h (p < 0.001), corresponding to 56% and 60% of inhibition, respectively. In postmenopausal women, inhibition of the elevated basal serum LH and FSH levels occurred after a single injection of the antagonist analog SB-75 in doses of 75, 150, 300, 600 and 1200 μg using im, sc and iv routes of administration. The mean resting levels of serum LH and FSH showed a significant decrease for all doses and routes of administration of SB-75 (p < 0.01). Maximal inhibition was observed 6–12 h after administration. After administration of 300 μg of SB-75 sc every 12 h for 3 days, serum LH and FSH continued to be secreted but a marked decrease in the basal levels of both gonadotropins was observed. A fall in LH and FSH also was produced in patients with gonadal dysgenesis who were given 300 μg of SB-75. The nadir of serum LH was 61 ± 9.6% for the iv route and 58.5 ± 7.5% for the sc route (p < 0.01); for serum FSH it was 51 ± 7.5% and 48.5 ± 7.5% (p < 0.01), respectively, of the baseline levels. These results show that the antagonistic analog SB-75 is devoid of allergenic effects, extremely active in small doses and can be administered safely to humans. The development of sustained delivery systems for SB-75 should facilitate the clinical use of this powerful LHRH antagonist. David Gonzalez-Barcena, Hospital de Especialidades Centro Medico La Raza, Seris Y Zaachila, Col. La Raza, Mexico D.F.

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