Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:Q86TM3 (cage)
 29,987 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The literature reveals contradictory data regarding whether or not male release LH acutely following coitus. Since it has been shown that repeated mating increases accessory sex organ weight, suggesting induction of gonadotrophin release, it seemed of interest to reinvestigate the issue. Male rats were divided into two groups: the mated group was provided with frequent mating ("experiencing") trials; the unmated group served as cage controls which received no sexual contact throughout the entire experiment. All rats were provided with chronic jugular cannulae. One set of serum samples was taken from each rat at 85 days, the second set at 115 days. On the two evening when sampling took place the mated rats were subdivided into three groups: "chamber" (placed in mating arena alone), "mount" (allowed two to five mounts, but no intromission), and "ejaculation" (mated through entire copulatory sequence). Serum sampling took place every 15 min during the hour following completion of mating (defined in the "ejaculation" group). On the day following the second sampling, autopsies were performed, and terminal serum samples were taken. LH, FSH, and prolactin were measured by radioimmunoassay. There were no significant differences in any hormone among the groups during the hour following mating nor in the terminal sample. However, the mated rats showed significantly greater seminal vesicle and ventral prostate weights than the cage controls at autopsy. Several hypotheses are offered to account for the latter findings.
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PMID:Effects of mating on serum LH, FSH, and prolactin and accessory tissue weight in male rats. 124 58

In an effort to determine the inductive component(s) of photic input in long day seasonal breeders, adult male Syrian hamsters (Mesocricetus auratus) were exposed to one of nine lighting conditions for a duration of 10 weeks: a light-dark cycle of 14 hours of light followed by 10 hours of dark (LD 14:10, a long photoperiod); LD 10:14 (a short photoperiod); a high frequency light-dark cycle of 1 hour of light and 1 hour of dark (LD 1:1); a higher frequency light-dark cycle of 1 minute of light and 1 minute of dark (LD 1m:1m); constant light (LL); constant dark (DD); feedback lighting (LDFB; a condition that illuminates the cage in response to locomotor activity); a feedback lighting neighbor control (LDFB NC; the animal receives the same light pattern as a paired animal in LDFB, but has no control over it); or reverse feedback lighting (rLDFB; a condition that darkens an illuminated cage in response to locomotor activity). Exposure to LL, LD 1:1, LD 1m:1m, LDFB and rLDFB significantly and similarly lengthened the free-running period of the locomotor rhythm when compared to the period of animals in DD. The paired tests and accessory reproductive glands weights, spermiogenesis, seminiferous tubule diameter and serum concentrations of testosterone, prolactin, LH and FSH, suggest that LD 14:10, LL, LD 1:1, rLDFB and LDFB NC maintain reproductive function in the Syrian hamster, while LD 10:14, DD, LD 1m:1m and LDFB do not. It is known that as little as two 1-second pulses of light are stimulatory if coincident with the subjective night (17.22). Thus, it is not surprising that LD 1:1 is stimulatory. LD 1m:1m is not stimulatory, however, despite an identical quanta of light per 24 hours and similar phase relationship. It appears that mere light exposure during the subjective night is not necessarily reproductively inductive. It would also appear that behaviorally generated light-dark cycles can be (i.e., LDFB), but are not necessarily (i.e., rLDFB) inhibitory to the maintenance of the reproductive system in long day breeders. Furthermore, the lighting pattern derived from LDFB is stimulatory if given exogenously (i.e., LDFB NC). Although it is not understood why light exposure that is coincident with the subjective night (i.e., LD 1m:1m and LDFB) is not stimulatory in long day breeders, a possible hypothesis is that an internal coincidence model is involved in the photoperiodic response and that multiple transitions during the subjective night may cause a dissociation of internal oscillations which must be in phase for light to be stimulatory.
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PMID:Nocturnal illumination does not necessarily stimulate the photoperiodic response, despite mimicking the effects of constant light on the circadian system in the male Syrian hamster. 211 74

In castrated Wistar rats four days of Rapid Eye Movement sleep (REMs) deprivation by the cuff pedestal method induced decrements in plasma LH and FSH. The adenohypophyseal levels of these hormones were decreased in the REMs-deprived rats and in the control rats kept on pedestals with the supporting cuff in the elevated position as compared with the home-cage control rats. The results are discussed in terms of regional brain metabolic activity and transmission.
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PMID:Rapid eye movement sleep deprivation depresses plasma FSH and LH in castrated rats. 251 Feb 4

The progressive cessation of regular ovulatory function in aging female rats is preceded by a significant decrease in the magnitude of the proestrous LH surge during regular estrous cycles. However, our recent study has demonstrated that normal LH secretion and regular estrous cycles can be maintained for an extended period of time in aging females housed with fertile males and allowed to undergo repeated pregnancies. Since progesterone (P) secretion is persistently increased in pregnant rats, the present study examined whether repeated increases in circulating progesterone accounted for these results. Starting at 8 months of age and continuing to 13 months, multiparous rats were grouped and treated as follows: controls: females were housed five per cage; mated: five females were housed with one fertile male and allowed to undergo repeated pregnancies; and P-implanted: females were housed five per cage and implanted sc with Silastic capsules containing P for 3 of every 4 weeks. During the 4.5 months of study, serum concentrations of estradiol (E2) in the P-implanted rats remained between 13 and 27 pg/ml, similar to levels in pregnant females (8-26 pg/ml) of the mated group. These E2 values were less than the preovulatory increase in serum E2 on proestrus (mean +/- SE, 56 +/- 10 pg/ml) in cyclic control females. In contrast, serum P values were persistently elevated in both the pregnant and the P-implanted rats, although the values in the latter (27-55 ng/ml) were about one third to one half of those in the former group (117-125 ng/ ml). All treatments were stopped at 13 months of age, and estrous cycle patterns were determined thereafter. Between 13 and 17 months of age, the percentages of regularly cycling rats were significantly (P less than 0.01) greater in the mated group (50%, 36%, and 15% at 13, 15, and 17 months, respectively) than in the control group (23%, 20%, and 9%, respectively). During this same period, 50% of the females from the P-implanted group continued to display regular cycles. By the age of 11 months, 8 of 21 untreated retired breeder females exhibited attenuated LH surges on proestrus and subsequently ceased to display regular estrous cycles within 2 months, whereas the other 13 rats showed normal LH and FSH surges and continued to maintain regular cycles. In contrast to these, aged female rats from the previously mated (15-month-old) and the P-implanted (19-month-old) groups exhibited normal profiles of proestrous LH and FSH surges during regular estrous cycles.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Relation of circulating estradiol and progesterone to gonadotropin secretion and estrous cyclicity in aging female rats. 392 47

Changes in gonadotropins, progesterone, cortisol, DHA, and DHAS were monitored in 10 female rhesus monkeys (Days 20-23 of the menstrual cycle) subjected to cage restraint with or without ketamine anesthesia for successive venipunctures. All animals were bled without sedation for 2 hr at 30-min intervals. Then 4 of the animals were anesthetized with ketamine-HCl and bleedings in all animals were continued for an additional 2.5 hr. FSH and progesterone were not appreciably affected by either restraint technique. LH declined steadily for the duration of the bleedings (P less than 0.05). Serum levels of cortisol and the adrenal androgens increased twofold (P less than 0.05). Anesthesia with ketamine had no effect on any of the six variables when compared with saline controls. Cortisol and dehydroepiandrosterone (DHA) levels tended to plateau (P less than 0.01) after 2 hr in both treated and control groups. In contrast, dehydroepiandrosterone sulfate (DHAS) levels increased continuously throughout the entire study period. These data indicate that ketamine anesthesia does not alter endocrine responses to venipuncture when administered following cage restraint of conscious animals. These findings further confirm the difficulties in obtaining estimates of basal levels of hormones which are responsive to stress and suggest that the first sample may provide the best estimate.
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PMID:Influence of restraint and ketamine anesthesia on adrenal steroids, progesterone, and gonadotropins in rhesus monkeys. 623 45

The regulation of pituitary GnRH receptors (GnRH-R) by gonadal steroids was examined in female mice housed in a constant environment (six to 8 per cage in same room as males). A 60% decrease in GnRH-R occurred 7 days after ovariectomy (OVX) (9.2 +/- 0.9 fmol/pituitary OVX vs. 25 +/- 2 for intact random estrous cycle controls). The receptor affinity (Ka 1.86 X 10(9) M-1) remained constant in intact and OVX female mouse pituitary particles. The pattern of GnRH-R fall after OVX was similar to that found in male mice, except that the GnRH-R decrease began some 6 h later than in males and serum LH also rose more slowly. Serum FSH was significantly elevated 6 h post OVX. In contrast to males, pituitary LH, in spite of a rapid fall (60%) at 12 h, regained the random, estrous cycle control value by 4 days post OVX and then increased to above this level. Pituitary FSH, unlike in males, remained at the intact value (3.1 +/- 0.24 micrograms/pituitary) up to 24 h post OVX and then gradually rose to 7.9 +/- 0.37 micrograms/pituitary on day 4 and 15.5 +/- 0.32 micrograms/pituitary on day 7. Treatment of OVX female mice with estradiol-17 beta (300 ng/day) attenuated the postcastration GnRH-R fall, and was more effective when combined with progesterone (375 micrograms/day). Progesterone alone was ineffective. The GnRH-R fall post OVX persisted for up to 2 months, despite elevated serum and pituitary LH and FSH levels. GnRH-R fell by 40% in lactating mice (20.6 +/- 0.95-lactating vs. 32.4 +/- 1.25 fmol/pituitary-random, estrous cycling females). Serum LH was reduced by 70% in lactating mice. These findings are qualitatively and quantitatively similar to those in lactating rats suggesting that, in this physiological situation, a similar mechanism may account for the receptor fall in both species. In sex reversed (Sxr) mice (genotypic female-phenotypic male) GnRH-R values were about 50% higher than those of intact normal male and normal, random estrous cycling, female values. This was the only situation in mice in which pituitary GnRH-R increases were observed to date. Serum and pituitary LH and FSH values in Sxr mice were elevated, especially when compared with normal, random estrous cycling female controls. The results indicate that pituitary GnRH-R of female mice fall in response to removal of gonadal steroid feedback, in the same way as males.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Pituitary gonadotropin-releasing hormone receptor regulation in mice. II: Females. 632 43

The photoperiodic effects of a periodic light pulse on neuroendocrine-gonadal activity in the male golden hamster was examined using a night interruption paradigm. Adult male hamsters that had been housed 3 to 5 per cage on LD 14:10 were placed either in individual cages, each equipped with a running wheel, or maintained in communal housing conditions, without access to a running wheel. Animals were then transferred to either LD 6:18 or to a LD 6:18 light cycle with a periodic 10-second night interruption (8 hours after lights off) occurring once every two, four, or seven days. As expected, exposure to LD 6:18 for 11 weeks induced complete regression of the testes and seminal vesicles, accompanied by low serum levels of LH and FSH, in both individually and communally-housed animals. However, in individually-housed animals receiving a 10-second night interruption every other day on LD 6:18, paired testis and seminal vesicle weights, as well as serum gonadotropin levels, were maintained at values comparable to those normally observed in hamsters exposed to photostimulatory long days. Furthermore, the presentation of a periodic 10-second night interruption once every four or seven days to individually-housed animals with access to a running wheel was sufficient to partially or totally block the inhibitory effects of short days on neuroendocrine-gonadal activity. Communally-housed hamsters receiving a 10-second light pulse once every two, four, or seven days also exhibited paired testis and seminal vesicle weights, as well as serum gonadotropin levels, that were consistently higher than the values obtained for animals exposed only to LD 6:18.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Periodic exposure to a brief light signal stimulates neuroendocrine-gonadal activity in golden hamsters. 642 51

Three experiments were performed to analyze the time course of demasculinization in the Japanese quail and to test the activating and organizing effects of estradiol (E2) in adult sexually active birds. In Experiment 1, males and females were castrated at the age of 1 day or 1, 2, 4, and 6 weeks and treated as adults with testosterone (T). The age of castration had no effect on behavior and morphology in males. Plasma gonadotrophins (LH and FSH) were, however, higher in males castrated at or before than in those castrated after 2 weeks of age. This suggests that postnatal testicular secretions have organizing effects on the pituitary activity. Females which were castrated before 1 week of age were less sensitive to the activating effects of T than males, but were not fully demasculinized. The demasculinization of different reproductive characteristics such as male sexual behavior, cloacal gland size, and weight of the syringeal muscles is achieved in females at different times posthatching. In Experiment 2, castration of male and female quail at the ages of 4 days or 4 weeks confirmed that postnatal ovarian secretions contribute to the full behavioral and morphological demasculinization of females. It is easier to elicit mounting in T-treated females when they are tested in their home cage instead of a test arena. This difference was not observed in males. During Experiment 3, it was impossible to demasculinize sexually active adult males or females by treatment with Silastic implants of E2. E2 did not maintain sexual behavior in ovariectomized females showing male sexual behavior when treated with T but maintained the behavior in males.
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PMID:The postnatal demasculinization of sexual behavior in the Japanese quail (Coturnix coturnix japonica). 643 61

Postweaning development was monitored in domesticated rabbits reared in single- or mixed-sex groups at a commercial farm. The results suggest that sex composition of cage groups had no significant effect on weight gain, feed intake or mortality rates from weaning (35 days) to marketing (93 days). On sacrifice at 93 days, females from single- and mixed-sex groups showed no significant differences in plasma gonadotropin levels (LH and FSH) or weights of paunched carcase, ovaries, uterus, adrenals, kidneys or kidney fat. Evidence for within-cage dominance hierarchies was found at 63 days of age when 46% of the rabbits inspected showed signs of aggressive attack.
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PMID:Effects of single- and mixed-sex caging on postweaning development in the rabbit. 654 Mar 34

Endocrine changes mediating male-induced estrus were examined in intact female mice which were rendered pseudopregnant by housing in groups. Adult female mice were placed in group cages on the day of estrus, and on day 5 of the ensuing pseudopregnancy, a mature male mouse was placed in the group cage. Animals were killed and serum levels of LH, FSH, PRL, estradiol, and progesterone were assayed over the 72 h after introduction of the male. During the first 24 h of male exposure, progesterone plummeted to basal levels. These events were followed by a gradual rise in serum estradiol, an increase in uterine weight, and an LH surge at 62 h which was followed by ovulation. PRL levels tended to be lower in treated females, but this was not significant. It is postulated that the initial exercise of the male is to destroy the corpus luteum of pseudopregnancy,presumably by suppressing luteal support. The question is raised of whether the male is also necessary to induce the subsequent LH surge or if suppression of the corpus luteum is sufficient for estrus to result.
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PMID:Changes in serum hormone levels associated with male-induced ovulation in group-housed adult female mice. 718 49


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