The Journal of endocrinology.
Publisher:
Society for Endocrinology. Bristol, UK : BioScientifica (2011)
Frequency: Monthly
Country: England
Language: English
Author(s):
Society for Endocrinology.
Start Year:1939 -
ISSN:
0022-0795 (Print)
1479-6805 (Electronic)
0022-0795 (Linking)
1479-6805 (Electronic)
0022-0795 (Linking)
Impact Factor
4
2022
| NLM ID: | 0375363 |
| (DNLM): | J19940000(s) |
| (OCoLC): | 01754564 |
| Coden: | JOENAK |
| LCCN: | 64005925 |
| Classification: | W1 JO642 |
Influence of foetal genotype on the follicle-stimulating hormone:luteinizing hormone ratio of pregnant mare serum gonadotrophin. Rat testicular radioreceptor assays specific for FSH and LH were used to determine the FSH:LH ratio of PMSG produced by horse, donkey, mule and hinny conceptuses. Measurements of FSH and LH activities in PMSG produced both in vivo and in vitro by the four types of conceptuses showed that the genotype of the foetus markedly influences the FSH:LH ratio of PMSG. The FSH:LH ratio of PMSG produced by the horse conceptus was around unity whereas the ratio of PMSG produced by the donkey conceptus was as low as 0-2. Furthermore, the hybrid mule and hinny conceptuses both produced PMSG with an FSH:LH r...
Pregnant mare serum gonadotrophin: ratio of follicle-stimulating hormone and luteinizing hormone activities measured by radioreceptor assay. Specific radioreceptor assays for FSH and LH, which employ tissue receptors from rat testis and highly purified human FSH (LER 1575-C) and LH (Hartree IRC-2, 24/6/69) as standards, have been developed to determine the FSH-like and LH-like activities in pregnant mare serum gonadotropin (PMSG). Measurements of FSH and LH concentrations in the serum of six pregnant Pony mares showed that the ratio of these two activities did not vary significantly between mares and remained constant between days 40 and 80 of gestation with a value of 1-45 +/- 0-04 (S.E.M.). The FSH:LH ratio of PMSG produced by cu...
The effect of gonadotrophins on fluid secretion and sperm production by the rat and hamster testis. Single intravenous injections of ovine luteinizing hormone (LH) in adult hamsters and rats had no effect on fluid secretion by the testes, as measured by the gain in weight or water content during a 10-h period after ligation of the efferent ducts (EDL). Neither was there any obvious effect on the liberation of spermatozoa, as judged by the total number of sperm in the unligated and EDL testes and from the concentration of spermatozoa in the secreted fluid, calculated from the difference between the number of sperm in the EDL and unligated testes divided by the difference in weight.
In adul...
Steroid content of the equine ovary during the reproductive cycle. Follicular fluid from individual follicles was collected from nine mares in oestrus and the concentration of the following steroids determined by gas—liquid chromatography: progesterone, 17α-hydroxyprogesterone, androstenedione, 19-norandrostenedione, epitestosterone, oestrone and oestradiol. The most vascular follicles, which were probably those destined to ovulate, tended to have the highest steroid concentrations. In these vascular follicles oestradiol was the main steroid found with an average concentration of 151 μg/100 ml.
In two out of three samples of follicular fluid taken from...
Studies on tissue culture of equine ovarian cell types: effect of gonadotrophins and stage of cycle on steroidogenesis. Granulosa cells were harvested from follicles of mares at various stages of the oestrous cycle and maintained in a tissue culture medium containing 15% horse serum, 30% medium '199' and 55% Hanks's solution. Between days 4 and 10 of culture the granulosa cells harvested from small follicles (1–2 cm. diam.) of mares in the midluteal phase of the cycle secreted an average of 0·36 pg. progesterone/cell/day. Cells harvested from large follicles of mares in the late and/or early oestrous stage of the cycle secreted an average of 29·5 pg. progesterone cell/day; the cells harvested from the large...
The effect of urea on the biological activity of gonadotrophins of placental, endometrial and urinary origin. Human chorionic gonadotrophin (HCG), pregnant mare serum gonadotrophin (PMSG) and human menopausal gonadotrophin (HMG) were incubated with varying concentrations of urea at different temperatures for different times.
The luteinizing hormone (LH) activity of HCG was progressively destroyed with increasing concentrations of urea. The degree of inactivation was greater at higher temperatures but the time of incubation did not affect the results.
The follicle-stimulating activity of PMSG was reduced at high urea concentrations; the time of incubation was without effect.
Under the experime...
Steroids in the follicular fluid and the corpus luteum of the mare. A ‘two-cell type’ theory of ovarian steroid synthesis. A comparison has been made between the steroids present in equine follicular fluid and luteal tissue. Follicular fluid was found to contain progesterone, 17α-hydroxyprogesterone, androstenedione, epitestosterone, 19-norandrostenedione, oestrone, oestradiol-17β and 6α-hydroxyoestradiol-17β, in confirmation of previous studies. On the other hand, luteal tissue contained large amounts of progesterone and 20α-hydroxypregn-4-en-3-one, and a small quantity of 17α-hydroxyprogesterone. No C18 or C19 steroids could be detected.
These findings are therefore interpreted as evidence in favour of ...