Adrenocorticosteroid activity in Lyon hypertensive (LH) and low blood pressure (LL) rat strains differ in several respects. Abnormal activity of 11beta-hydroxysteroid dehydrogenase enzymes (11beta-HSD1 and 11beta-HSD2), which interconvert corticosterone and inactive 11-dehydrocorticosterone, might contribute to the LH phenotype by regulating corticosteroid hormone access to receptors. 11beta-HS...

Adrenocorticosteroid activity in Lyon hypertensive (LH) and low blood pressure (LL) rat strains differ in several respects. Abnormal activity of 11b-hydroxysteroid dehydrogenase enzymes (11b-HSD1 and 11b-HSD2), which interconvert corticosterone and inactive 11-dehydrocorticosterone, might contribute to the LH phenotype by regulating corticosteroid hormone access to receptors. 11b-HSD2 (expresse...

Since the male gonad is a target organ of both pituitary hormones and androgens, the present study was performed to determine whether testicular aryl hydrocarbon hydroxylase (AHH), epoxide hydrase (EH), and glutathione transferase activities and cytochrome P-450 levels were regulated by follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone. Intact, sham-operated control...

Lysyl hydroxylase (EC1.14.11.4, LH) catalyzes post-translationally the hydroxylation of lysyl residues in collagens and other proteins with collagenous domains. Hydroxylysyl residues may also be glycosylated by hydroxylysyl galactosyltransferase (EC 2.4.1.50, GT) or galactosylhydroxylysyl glucosyltransferase (EC 2.4.1.66, GGT) to form galactosylhydroxylysyl or glucosylgalactosylhydroxylysyl res...

The meiotic cell cycle of mammalian oocytes in preovulatory follicles is held in prophase arrest by diffusion of cGMP from the surrounding granulosa cells into the oocyte. Luteinizing hormone (LH) then releases meiotic arrest by lowering cGMP in the granulosa cells. The LH-induced reduction of cGMP is caused in part by a decrease in guanylyl cyclase activity, but the observation that the cGMP p...

The effects of third ventricular injection of beta-endorphin (beta-EP) on spontaneous, brain stimulation-induced and estrogen-induced LH surges were studied in the adult female rat. It was found that beta-EP blocked the preovulatory surge of LH release and ovulation, while it did not affect LH release in response to LH-RH injection. The site of the beta-EP blockade of ovulation was proved to be...

The experiment was conducted on 14 postpartum mithun (Bos frontalis) cows to establish the preovulatory LH and FSH surge patterns during estrus in peripheral circulation. Blood samples from jugular vein were collected every 2 h until 72 h and on alternate days till day 22 (day 0 = day of estrus) following the day of estrus onset. Plasma progesterone (P4), LH and FSH levels were estimated. Plasm...

In an attempt to study the role of glucokinase (GK) and the effects of glucose and peptides on GK gene expression and on the activity of this enzyme in the hypothalamus, we used two kinds of biological models: hypothalamic GT1-7 cells and rat hypothalamic slices. The expression of the GK gene in GT1-7 cells was reduced by insulin (INS) and was not modified by different glucose concentrations, w...

Twenty-four adult female Sprague-Dawley rats (3 from each of 8 litters), showing 4-day cycles, were used in the present study. Aqueous extracts of pools of 6 pituitary glands in each cycle date were fractionated with a column isoelectrofocusing (IEF) technique, pH range of 3.5-10. Biological and immunological LH activities were determined by an in vitro bioassay and a radioimmunoassay, respecti...