THE URINARY EXCRETION OF GONADOTROPHINS BY SHEEP: EXTRACTION PROCEDURE AND DAY-TO-DAY FLUCTUATION IN EXCRETION BY MALE AND FEMALE CASTRATED SHEEP

1964 ◽  
Vol 29 (3) ◽  
pp. 215-228 ◽  
Author(s):  
R. B. SYMINGTON
Keyword(s):  
Luteinizing Hormone ◽  
Urinary Excretion ◽  
Follicle Stimulating Hormone ◽  
Extraction Procedure ◽  
Slight Modification ◽  
Original Method ◽  
Male And Female ◽  
Diethylaminoethyl Cellulose ◽  
Daily Excretion ◽  
Rate Of Recovery

SUMMARY The application of Johnsen's tannic acid method to the extraction of gonadotrophins from ovine urine was studied using the urine of castrated sheep. Slight modification of the original method increased the efficiency of extraction. Rate of recovery was measured at several levels of added pituitary and urinary gonadotrophins and was similar to recovery rates reported for human urines (30–81 %). Reproducibility of the extraction procedure was excellent. Further purification of the final ethanol precipitate without loss in potency was effected by chromatography using diethylaminoethyl cellulose. The daily excretion of total gonadotrophic activity, follicle stimulating hormone and luteinizing hormone by two male and one female castrated sheep was estimated for four periods each of 3 weeks. In all instances excretory levels fluctuated considerably and randomly. Levels of excretion of all types of gonadotrophic activity were much lower than in man.

CHANGES IN SECRETION OF LUTEINIZING HORMONE AND FOLLICLE-STIMULATING HORMONE INDUCED BY HYPOVOLAEMIA IN RATS

1981 ◽  
Vol 88 (1) ◽  
pp. 97-101 ◽  
Author(s):  
V. W. K. LEE ◽  
D. M. DE KRETSER
Keyword(s):  
Luteinizing Hormone ◽  
Blood Volume ◽  
Follicle Stimulating Hormone ◽  
Blood Sampling ◽  
Female Rats ◽  
Male And Female ◽  
Male And Female Rats ◽  
Egg Albumen ◽  
Stimulating Hormone

Changes in levels of LH and FSH in the circulation were examined during repeated blood sampling in untreated rats and gonadectomized male and female rats treated with oestrogen, progesterone and thyroxine. Blood depletion induced a significant increase in levels of LH in steroid-treated rats but the increase was abolished when the depleted blood volume was replaced with egg albumen. The rise in LH was less dramatic in male than in female animals. In untreated rats, levels of LH either decreased or did not change with repeated phlebotomy. In contrast, the levels of FSH either did not alter or were lowered in all situations.

Luteinizing hormone, follicle-stimulating hormone, testosterone and dihydrotestosterone during testicular descent in the pig fetus

1996 ◽  
Vol 8 (7) ◽  
pp. 1115 ◽  
Author(s):  
JH Visser ◽  
CF Heyns
Keyword(s):  
Luteinizing Hormone ◽  
Body Mass ◽  
Follicle Stimulating Hormone ◽  
Linear Increase ◽  
Testicular Descent ◽  
Serum Concentrations ◽  
Male And Female ◽  
Androgen Synthesis ◽  
Significant Difference ◽  
Stimulating Hormone

To investigate the relationship between gonadotrophins, androgens and testicular descent in the pig fetus, serum concentrations of luteinizing hormone (LH) and follicle-stimulating hormone (FSH), and serum concentrations and testicular content of testosterone (T) and 5 alpha-dihydrotestosterone (DHT) were determined by radioimmunoassay in 95 fetuses (48 males, 47 females) between Day 60 and Day 90 post coitum (p.c.). The testes were descended in 0% of fetuses at Day 60, 8% of fetuses at Day 70, 40% of fetuses at Day 80 and 87% of fetuses at Day 90 p.c. There was a significant increase in mean serum concentrations of LH in both male and female fetuses from Day 60 to Day 90, with a significant difference in mean serum concentrations of LH between male fetuses with a body mass < 350 g (4% of testes descended) and those with a body mass > 450 g (87% of testes descended), but not between male and female fetuses < 350 g or > 450 g in body mass. There was no significant difference in mean serum concentrations of FSH between male and female fetuses. Mean serum concentrations of T were significantly higher in male fetuses at Day 60 than in those at Days 70-90, with no significant difference in serum concentrations of DHT from Day 60 to Day 90 p.c. Testicular content of T and DHT showed a non-linear increase from Day 60 to Day 90 p.c. Although the serum concentration of T is elevated before, and decreased during, the period of descent, the testicular content of T and DHT increases during the period of descent, indicating that serum concentrations of LH and FSH may have an indirect effect on descent by stimulating testicular androgen synthesis.

THE URINARY EXCRETION OF GONADOTROPHINS BY SHEEP: THE EFFECT OF SOME NUTRITIONAL FACTORS ON THE EXCRETION OF GONADOTROPHINS BY CASTRATED MALE SHEEP

1964 ◽  
Vol 29 (3) ◽  
pp. 229-234 ◽  
Author(s):  
R. B. SYMINGTON
Keyword(s):  
Luteinizing Hormone ◽  
Urinary Excretion ◽  
Urine Output ◽  
Follicle Stimulating Hormone ◽  
Temporal Fluctuation ◽  
Nutritional Factors ◽  
Daily Output ◽  
Merino Sheep ◽  
The Mean ◽  
Male Sheep

SUMMARY Male castrated Merino sheep were fed indoors on a dry ration or grazed on a good quality pasture. Despite the much greater urine volumes excreted by the grazing animals, the mean daily rates of excretion of total gonadotrophic activity and follicle-stimulating hormone (FSH) were very similar in the two groups. Corresponding levels of excretion of luteinizing hormone (LH) were very variable, owing apparently to deficiencies in the assay technique. When sheep were fed indoors on freshly cut grass, the urine output was almost three-quarters of that of grazing animals but the rate of excretion of total gonadotrophic activity and of FSH was considerably greater than that of grazing animals. The daily output of urine by sheep fed indoors on a dry ration was adjusted to equal that of grazing sheep. Although the amounts of total gonadotrophic activity were smaller than those in the previous experiments, the amounts of FSH excreted were the highest recorded in the entire investigation. The possibility of a temporal fluctuation in the excretion of gonadotrophins is discussed.

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