Effect of rabbit antiserum to sheep pituitary interstitial-cell stimulating hormone in immature female rats

The daily injection of anti-sheep ICSH serum (A/S) for 9 days into immature male rats (30 days initial age) not only resulted in a 79 % inhibition of testes weight gain as compared to the testes of controls injected with normal rabbit serum (NRS), but caused these organs to ascend into the inguinal canal. This was accompanied by a complete suppression of spermiogenesis in the A/S-injected animals, whereas the testes of all NRS-injected animals showed the presence of spermatozoa in some of the tubules.Administration of A/S to young adult male rats resulted in a 45% suppression of testicular weight, an 86% inhibition of prostate weight and a similar degree of involution of the seminal vesicles. Spermatozoa obtained from the vas deferens of the NRS-injected adult animals were highly active, while those taken from the A/S treated animals were completely immotile.

Section: Introductionmentioning

confidence: 73%

Section: Introductionmentioning

confidence: 84%

Inhibition of Spermiogenesis, Prostate and Seminal Vesicle Development in Normal Animals With Anti-Gonadotrophic Hormone Serum

Hayáshida¹

1963

“…In this study it was observed that the interstitial cells in the testes of the normal rats given antiserum were as deficient as those seen in hypophysectomized control animals ; yet there was no detectable effect of the antiserum on gain in body weight or on weights of adrenals or thymus. It was shown in other studies in the normal female rat (Bourdel, 1961) that administration of rabbit antiserum to puri¬ fied ovine ICSH resulted in some decrease in ovarian weight, the extent of decrease being correlated with the amount of antiserum injected. In all instances uterine weights were suppressed to a greater degree than were the ovarian weights.…”

Section: Discussionmentioning

confidence: 92%

Neutralization of Activity of Circulating Gonadotrophic Hormones by Antiserum to Rat Pituitary

Contopoulos¹,

Hayáshida²

1963

Antiserum prepared by the immunization of rabbits, with homogenates of rat anterior pituitary gland according to a procedure previously outlined, was absorbed with homologous serum proteins and tissues to remove various non-specific antibodies.Varying levels of plasma from gonadectomized male rats, containing high levels of gonadotrophic hormone activity, were injected into hypophysectomized, immature female rats. The simultaneous injection of antiserum resulted in complete neutralization of gonadotrophic hormone as judged by the inhibition of ovarian and uterine weight responses and the extent of follicular development in the ovaries of the rats used for the bioassay. The degree of inhibition was dependent upon the relative amount of antiserum employed. Normal rabbit serum did not have any inhibitory effect. No detectable non-specific or toxic effects were noted in the animals injected with antiserum.

“…Thus, in animals kept under controlled lighting conditions with illumination from 5 a.m. to 7 p.m. the critical period is between 2 and 4 p.m., ovulation occurring between 1 and 2.30 a.m. the next day. Bourdel (1961) showed that rabbit anti-ovine-LH serum could neutralize endogenous LH in immature female rats, and more recently Bourdel & Li (1963) found that this antiserum, when injected into adult female rats daily for 12 days beginning 36 hr. in advance of presumed oestrus, could suppress this oestrus and subsequent ones.…”

mentioning

confidence: 97%

The Suppression of Ovulation in the Rat by Rabbit Anti-Ovine-Lh Serum

Kelly¹,

Robertson²,

Stansfield³

1963

It has been demonstrated in the rat that on the day of prooestrus there is a critical period for the initiation of the release of the 'ovulating gonadotrophic complex' from the pituitary gland (Everett, 1952). Thus, in animals kept under controlled lighting conditions with illumination from 5 a.m. to 7 p.m. the critical period is between 2 and 4 p.m., ovulation occurring between 1 and 2.30 a.m. the next day. Bourdel (1961) showed that rabbit anti-ovine-LH serum could neutralize endogenous LH in immature female rats, and more recently Bourdel & Li (1963) found that this antiserum, when injected into adult female rats daily for 12 days beginning 36 hr. in advance of presumed oestrus, could suppress this oestrus and subsequent ones. If the first injection were given only 12-16 hr. in advance, the first expected oestrus occurred normally, although subsequent oestrous periods were suppressed. Similarly, Young, Nasser & Hayashida (1963) found that daily injections for 11 days of an antiserum prepared against purified sheep LH inhibited the oestrous cycle in mature female rats.The work reported here was designed to demonstrate whether antiserum to ovine LH administered at the time of the release of the ovulating gonadotrophic complex would prevent ovulation. LH was prepared from ovine pituitary glands by the method of Ward, McGregor & Griffin (1959), assayed by the ovarian ascorbic-acid depletion method of Parlow (1961) and shown to have the same order of potency as the NIH-S-LHX preparation.Antiserum to this LH preparation was prepared in two rabbits according to the method of Moudgal & Li (1961). A measure of the potency of the pooled antiserum was obtained by the graded neutralization of ovine LH in vitro by varying concen¬ trations of antiserum. The residual activity of the supernatant was estimated by the Parlow assay. Gel-diffusion studies following the method of Ouchterlony (1953) gave evidence for the presence of a single antigen-antibody system. Sexually mature virgin female rats of the Sprague-Dawley strain were used. Ovulation was confirmed by counting the ova in the fallopian tubes.The injections of antiserum were given at approximately the time of initiation of the release of the Ovulating gonadotrophic complex' from the pituitary, i.e. at approximately 12 hr. before the expected ovulation. A vaginal smear was obtained from each rat on the following morning before it was killed. The ovaries were fixed for subsequent histological examination. A preliminary experiment showed that the