The physiological and pathophysiological role of cortisol in pulsatile LH release was investigated in 14 patients (5 men, 6 premenopausal women, and 3 postmenopausal women) with Addison’s disease. The explicit effect of cortisol in relation to the effect of corticotropin-releasing factor (CRF), ACTH, and opioids was ensured by hypo-, normo-, and hypercortisolism. Hypocortisolism was obtained by...

In previous work we have shown that GABAB receptors are required for expression of absence seizures in the lethargic (lh/lh) mouse model; that lh/lh mice have increased numbers of GABAB binding sites compared to nonepileptic littermates (designated +/+); and that the magnitude of the increased number of GABAB receptors in lh/lh mice correlated positively with the frequency of absence seizures. ...

The endocrine and ovarian effects of hypophysectomy (n = 5) and gonadotrophin-releasing hormone (GnRH) antagonist administration (Antarelix) (n = 5) were studied in gilts by comparison with control animals (n = 6). All gilts were given Regumate (20 mg/d for 18 d). The last day of Regumate was day 0. Hypophysectomy and initiation of Antarelix administration (0.6 mg iv twice daily for 7 d) were p...

BACKGROUND The role of LH in sensitizing antral follicles to FSH is unclear. LH is required for normal hormone production and normal oocyte and embryo development, but follicular responses to LH may depend upon the stage of development. Potential roles at the early follicular phase were explored in a clinical setting by employing a sequential approach to stimulation by recombinant human (r-h) L...

Atrazine (ATZ) was administered daily by gavage to pregnant female Sprague Dawley rats at doses of 0, 6.25, 25 or 50 mg/kg/day, either during gestation, lactation and post-weaning (G/L/PW cohort) to F1 generation female offspring or only from postnatal day (PND 21) until five days after sexual maturation (vaginal opening) when the estrogen-primed, luteinizing hormone (LH) surge was evaluated (P...

Aim of this study was to evaluate the effect of vitamin D supplementation in obese, insulin resistant and vitamin D deficient PCOS women on biochemical and clinical hyperandrogenism and menstrual irregularity in comparison to effect of metformin or combined metformin plus vitamin D therapy. Thirty nine PCOS women were randomized into three groups and treated with alfacalcidiol (Group 1), combin...

Activity of adenylate cyclase [(EC 4.6.1.1) ATP pyrophosphate lyase (cyclizing)] in purified rat ovarian plasma membranes undergoes partial desensitization (30-60%) upon exposure to saturating lutropin (LH, 0.1 p ~ ) and GTP (1 p ~ ) . Decline in hormone responsiveness of the enzyme is dose-dependent with regard to LH ( K , = 1.7 IWI +. 1) and GTP ( K , = 0.19 p~ f 0.02), indicating that the ac...

In female rodents, hypothalamic norepinephrine (NE) has a role in stimulating the secretion of gonadotropin-releasing hormone (GnRH) that triggers the ovulatory surge of luteinizing hormone (LH). NE synthesis from dopamine (DA) is catalyzed by dopamine-beta-hydroxylase (DbetaH) which contains a copper cofactor. Sodium dimethyldithiocarbamate (DMDC) is a pesticide with metal chelating properties...