We have previously shown that administration of antiprogestin (AP) type II RU486 to ovariectomized (OVX) rats on the morning of pro-oestrus decreases the magnitude of preovulatory gonadotrophin surge. This suggests that the effect of RU486 on LHRH-dependent gonadotrophin release may be independent of its ability to block progesterone actions. The aim of the present research was to study the pos...

Luteinizing hormone-releasing hormone (LHRH) neurons migrate from the olfactory placode to the forebrain in association with vomeronasal nerves (VNN) that express the polysialic acid-rich form of the neural cell adhesion molecule (PSA-NCAM). Two approaches were used to investigate the role of PSA-NCAM: injection of mouse embryos with endoneuraminidase N, followed by the analysis of LHRH cell po...

Forty crossbred boars were equally divided into eight groups at birth. Four groups were immunized (200 micrograms/boar) at 12 wk of age against either luteinizing hormone-releasing hormone (LHRH) conjugated to human serum globulin (LHRH-hSG) in complete Freund's adjuvant (CFA), LHRH-hSG in muramyldipeptide adjuvant (PEP), procine luteinizing hormone (LH) conjugated to hSG (pLH-hSG) in CFA or ov...

To study the Ca2+ dependency of luteinizing hormone-releasing hormone (LHRH) release in the bullfrog sympathetic ganglia, a method was developed to fill the preganglionic nerve terminal boutons with membrane-impermeant fura-2. We found that as stimulation frequency increased from 0.5 to 40 Hz, the peak [Ca2+]i ([Ca2+]p) and the rate of rise in [Ca2+]i increased, the decay of [Ca2+]i transients ...

The activity of estradiol on the LHRH neuronal network is crucial in the regulation of reproduction. In vivo, estradiol induces galanin (GAL) gene expression in LHRH neurons and GAL/LHRH colocalization is sexually dimorphic and neonatally determined by steroid exposure. The effects of estradiol on LHRH neurons, however, are considered to be indirect because estrogen receptors (ER) have not been...

We designed, synthesized, and evaluated in vitro and in vivo a novel targeted anticancer polymeric prodrug containing multiple copies of tumor targeting moiety [synthetic luteinizing hormone-releasing hormone (LHRH) peptide, analog of LHRH] and anticancer drug (camptothecin). One, two, or three molecules of the targeting peptide and anticancer drug were covalently conjugated with bis(2-carboxye...

Background: Androgen deprivation therapy (ADT) by surgical or medical castration is recommended for advanced or metastatic prostate cancer. Recent literature suggests that medical castration by luteinizing hormone receptor hormone (LHRH) antagonists might have advantages over treatment with LHRH agonists in patients with metastatic prostate cancer when prostate specific antigen (PSA) progressio...

Background. Most patients with metastatic prostate cancer are endocrinologically treated with LHRH agonist, but finally castration-refractory and hormone-refractory cancers occur. Serum testosterone levels get low to "the castration level" by LHRH agonists but may not get low enough against castration-refractory prostate cancer. Methods. As case series, twelve patients suffering from hormone-re...

Caspian kutum, Rutilus frisii kutum, is one of the most commercially important fish species in the Caspian Sea, but there are few reports about the endocrinology of induced spawning in this fish. In the present study, 54 individuals of female broodstocks of Kutum were studied for quantity and quality of propagation index, during March and April 2007. Hormone treatments include: LHRH-A2 (1 ?g kg...

The present study was aimed to examine the possible functional relationship between melatonin and hypothalamic transmitters, endogenous opioids and excitatory amino acids in controlling gonadotropin secretion in ovariectomized estrogen-primed rats. An intravenous injection of naloxone (mu opioid receptor antagonist), N-methyl-D-aspartate (NMDA; NMDA receptor agonist) or luteinizing hormone-rele...