Now showing items 1-10 of 64
Effect of fasting, refeeding, and dietary fat restriction on plasma leptin levels
(Endocrine Society, 1997-02)
The factors responsible for the variability in plasma leptin levels observed among individuals with similar body compositions remain unclear. To examine the impact of dietary variables, we compared the changes in leptin levels induced by fasting and dietary fat restriction with the expected decrease ...
Sexual dimorphism of growth hormone-releasing hormone and somatostatin gene expression in the hypothalamus of the rat during development
(Endocrine Society, 1991-05)
The secretory pattern of GH secretion is markedly sexually dimorphic in the adult rat. The patterning of GH secretion is determined by the coordinated activity of somatostatin (SS)- and GH-releasing hormone (GHRH)-containing neurosecretory cells located in the hypothalamus. In this study we examined ...
Regulation of somatostatin and growth hormone-releasing hormone gene expression in the rat brain
We have studied the regulation of somatostatin (SS) and growth hormone-releasing hormone (GHRH) gene expression in the brain of the laboratory rat. We report that hypophysectomy in the adult male reduces SS mRNA in cells of the periventricular nucleus (PeN), while GH reverses this effect. We ...
Ultradian luteinizing hormone and testosterone rhythms in the adult male monkey, Macaca fascicularis
(Endocrine Society, 1980-11)
No abstract or description.
Leptin is a metabolic signal to the reproductive system
(Endocrine Society, 1996-07)
Leptin, a newly-discovered hormonal product of the obese (ob) gene, is expressed by adipocytes and thought to play a role in the regulation of food intake and metabolism. We tested the hypothesis that leptin signals metabolic information to the reproductive system by examining its effects on the ...
Leptin is a metabolic gate for the onset of puberty in the female rat
(Endocrine Society, 1997-02)
The timing of puberty onset in mammals is tightly coupled to the animal's nutritional and metabolic state. We conducted two experiments to test the hypothesis that leptin acts as a metabolic signal for the onset of puberty. In the first experiment, we administered leptin (6.3 micrograms/g twice ...
Regulation of galanin gene expression in gonadotropin-releasing hormone neurons during the estrous cycle of the rat
(Endocrine Society, 1993-04)
Galanin is colocalized with GnRH in neurons of the hypothalamus and basal forebrain of female rats, and this neuropeptide may play a role in the generation of the midcycle surge of gonadotropin secretion. We tested the hypothesis that galanin gene expression in GnRH cells increases during proestrus. ...
Pubertal changes in gonadotropin-releasing hormone and proopiomelanocortin gene expression in the brain of the male rat
(Endocrine Society, 1989-04)
Pubertal development in mammals is in part attributable to a brain-dependent process, whereby increased pulsatile GnRH secretion leads to the awakening of the entire reproductive system. However, the brain mechanisms controlling this event are unknown. The apparent increase in GnRH secretion at ...
Growth hormone-releasing hormone messenger ribonucleic acid in the hypothalamus of the adult male rat is increased by testosterone
(Endocrine Society, 1990-09)
Since intact adult male rats have higher GH pulse amplitude than do castrated animals and since GH-releasing hormone (GHRH) secretion is predominantly responsible for the production of these GH pulses, we hypothesized that testosterone stimulates GHRH synthesis in neurons of the hypothalamus. To ...
Gonadotropin-releasing hormone messenger ribonucleic acid levels are unaltered with changes in the gonadal hormone milieu of the adult male rat
(Endocrine Society, 1990-08)
Testicular function is regulated by the negative feedback effect of sex hormones acting at the brain and pituitary to inhibit the secretion of LH and FSH. An important component of this feedback axis is presumed to involve regulation of secretion and possibly synthesis of GnRH by the brain. We ...