Nitric oxide (NO) affects reproductive processes both at the level of the brain and reproductive tract and this review is focused on its role as an essential regulator of the hypothalamic control of reproduction. The data gathered indicate that glutamate stimulates noradrenergic neurons which subsequently activate NO-ergic cells via alpha1-adrenergic receptors. The released NO diffuses into lut...

The requirements of purified rat Leydig cells for intra- and extra-cellular Ca2+ during steroidogenesis stimulated by LH (lutropin), cyclic AMP analogues and LHRH (luliberin) agonist were investigated. The intracellular Ca2+ concentrations ([Ca2+]i) were measured by using the fluorescent Ca2+ chelator quin-2. The basal [Ca2+]i was found to be 89.4 +/- 16.6 nM (mean +/- S.D., n = 25). LH, 8-brom...

The vomeronasal system of mammals is a specialized chemosensory pathway that parallels the main olfactory system but is anatomically distinct from its peripheral aspect through its projections into the central nervous system.'.' Recent evidence suggests a predominant role for the vomeronasal system in conveying the influence of odor stimuli upon neuroendocrine and on a variety of motivated beha...

Reproduction is adversely affected by alcohol abuse in humans and laboratory animals. In rats, alcohol exposure suppresses both luteinizing hormone (LH) and sex steroid secretion, although consensus is lacking as to which level of the hypothalamic-pituitary-gonadal (HPG) axis is primarily affected. We tested the hypothesis that acute alcohol treatment inhibits the HPG axis by blunting release o...

Endogenous opioids participate in the regulation of gonadotropin secretion through an influence on the release of the hypothalamic LHRH. However, it is not clear whether opioids exert a direct effect on LHRH-producing neurons or interfere with other systems able to influence LHRH release. A neuronal LHRH-producing cell line (GT1) developed recently provides a good model to study the mechanisms ...

DESCRIPTION TRELSTAR  DEPOT contains a pamoate salt of triptorelin, and triptorelin is a synthetic decapeptide agonist analog of luteinizing hormone releasing hormone (LHRH or GnRH) with greater potency than the naturally occurring LHRH. The chemical name of triptorelin pamoate is 5-oxo-L-prolyl-L-histidyl-L-tryptophyl-L-serylL-tyrosyl-D-tryptophyl-L-leucyl-L-arginyl-L-prolylglycine amide (pam...

We studied the response of plasma 7B2 to LHRH and ovine corticotropin releasing hormone (o-CRH) in healthy young subjects. The plasma 7B2 concentration significantly increased from 78.3 +/- 7.5 (mean +/- SEM) to 102.0 +/- 6.0 ng/L (142.7 +/- 12.7% of the basal value; P less than 0.01) following iv administration of LHRH in seven young subjects. On the other hand, no increase in plasma 7B2 was f...

AIM To compare treatment costs with alternative luteinizing hormone-releasing hormone (LHRH) agonist preparations and determine whether a leuprorelin solid implant is associated with potential cost savings. PATIENTS & METHODS A hypothetical population of 1000 prostate cancer patients was apportioned between the three most commonly-prescribed LHRH agonist preparations. Differentiated annual co...

Although castration levels of serum androgens are consistently achieved after 2-3 weeks of treatment with luteinizing hormone-releasing hormone (LHRH) agonists, the administration of these peptides alone in adult men is always accompanied by a transient increase in plasma testosterone and dihydrotestosterone levels, which lasts for 5-15 days at the beginning of treatment and is accompanied by d...