This study investigates ovulation and egg deposition behaviors in the anuran Eleutherodactylus coqui from Puerto Rico in response to stimulation with gonadotropin and gonadotropin releasing hormones. Five hormones were tested by injection over a range of doses, including mammalian LHRH, avian LHRH, fish LHRH, D-Ala6, des-Gly10 ethylamide LHRH and hCG. We report a low level of ovulation and egg ...

There are few options for treating hormone-refractory prostate cancer (PC). Various studies indicate that luteinizing hormone-releasing hormone (LHRH) agonists may have a direct inhibitory effect on prostate tumors mediated by specific LHRH receptors. One study evaluated LHRH receptors in hormone-dependent PC tissue, but no data have thus far been obtained on the presence of LHRH receptors in b...

INTRODUCTION Luteinizing hormone-releasing hormone (LHRH) analogues are widely used for the treatment of advanced hormone-dependent prostate cancer. However, there are currently no clinical guidelines for switching between LHRH analogues. It has been reported that there may be clinical benefits for patients switching between different formulations of LHRH agonists, as well as from an LHRH agoni...

Progesterone induces a LHRH surge in estrogen-primed ovariectomized rhesus monkeys, with a concomitant increase in the pulse frequency of neuropeptide Y (NPY) release. However, the role for NPY in the positive feedback action of progesterone on LHRH release in primates is unknown. The present study examines the effect of an antisense oligodeoxynucleotide for NPY messenger RNA (AS NPY) on the pr...

The middle-age decline in reproductive function is manifested by reduced LHRH release, resulting in a decreased magnitude and delay of onset of the LH surge. Earlier studies suggested that the reductions in LHRH neural activation in middle-aged rats resulted from deficits in the afferent drive to the LHRH neurons. One critical afferent to the LHRH neurons lies in the anteroventral periventricul...

To study the mechanism by which estradiol induces a preovulatory surge of follicle stimulating hormone (FSH), we concluded experiments designed to determine: (1) the time course of change in luteinizing hormone releasing hormone (LHRH)-induced FSH release after estradiol in vivo, and (2) whether LHRH is required to trigger the FSH surge. Steers were given 1 microgram LHRH at 20-min intervals fo...

Luteinizing hormone-releasing hormone (LHRH) neurons migrate from the vomeronasal organ (VNO) to the forebrain in all mammals studied. In mice, most LHRH neuron migration is dependent on axons that originate in the VNO but bypass the olfactory bulb and project into the basal forebrain. Thus, cues that regulate the trajectories of these vomeronasal axons are candidates for determining the destin...

Previous studies indicated that there is a separate hypothalamic control of follicle-stimulating hormone (FSH) release distinct from that of luteinizing hormone (LH). An FSH-releasing factor (FSHRF) was purified from rat and sheep hypothalami, but has not been isolated. We hypothesized that FSHRF might be an analogue of mammalian luteinizing hormone-releasing hormone (m-LHRH) and evaluated the ...

This study was undertaken to test the effect of immunization against luteinizing hormone-releasing hormone (LHRH) fusion proteins on the development and progression of prostate cancer in the transgenic adenocarcinoma mouse prostate (TRAMP) model. Two LHRH fusion proteins, ovalbumin with seven LHRH peptides (OV-LHRH-7), and thioredoxin with seven LHRH peptides (TH-LHRH-7) were used in a cocktail...

An experiment was conducted to determine if exogenous luteinizing hormone-releasing hormone (LHRH) administered iv intermittently as pulses (P) or by continuous sc infusion (I) using osmotic minipumps could sustain pulsatile LH release and induce estrous cyclicity in prepubertal heifers. Prepubertal heifers were assigned randomly to: 1) receive pulses of LHRH (n = 6; 2.5 micrograms LHRH/2 h for...