Decreased Type 2 Corticotropin-Releasing Hormone Receptor mRNA Expression in the Ventromedial Hypothalamus during Repeated Immobilization Stress

Oct 12, 1999Neuroendocrinology

Lower levels of stress hormone receptor gene in the brain's energy control area during repeated physical restraint stress

AI simplified

GLP-1 Therapies on OpenScience ↗PubMed ↗DOI ↗

Abstract

Rats subjected to 6 days of immobilization stress showed a reduction in food intake and body weight.

Immobilized rats exhibited higher levels of corticotropin-releasing hormone (CRH) mRNA in the paraventricular nucleus compared to controls.
Plasma insulin and leptin concentrations were lower in stressed rats.
Type 2 CRH receptor mRNA levels in the ventromedial hypothalamus decreased following repeated immobilization.
Neuropeptide Y (NPY) mRNA in the arcuate nucleus and galanin mRNA in the dorsomedial hypothalamus increased after stress.
Pro-opiomelanocortin (POMC) mRNA in the arcuate nucleus decreased with repeated immobilization.
These changes in neuropeptide mRNAs may counteract the anorectic effects of CRH.

AI simplified

Chronic or repeated stress results in reduction of food intake and body weight in rats. Stress-induced anorexia has been attributed to increased corticotropin-releasing hormone (CRH) function in the central nervous system. To explore possible roles of other neuropeptides and peripheral hormones involved in food intake and energy utilization during continuing stress, we examined the impact of repeated immobilization stress on expression of mRNAs coding for CRH, neuropeptide Y (NPY), galanin and pro-opiomelanocortin (POMC) mRNAs in such hypothalamic nuclei as the paraventricular nucleus (PVN), arcuate nucleus (ARC) and dorsomedial hypothalamus (DMH), as well as plasma insulin and leptin concentrations. Changes in type 2 CRH receptor (CRHR-2) mRNA in the ventromedial hypothalamus (VMH), a possible target of anorectic CRH effect, were also examined. Rats were immobilized for 2 h daily for 6 days and sacrificed 24 h after the last immobilization. Immobilized rats had lower food intake and body weight and higher levels of PVN CRH mRNA than controls. Repeated immobiliza tion also lowered plasma insulin and leptin concentrations and VMH CRHR-2 mRNA levels. These results provide additional evidence linking VMH CRHR-2 mRNA levels to plasma leptin concentration. ARC NPY and DMH galanin mRNAs increased following repeated immobilization, while ARC POMC mRNA decreased. DMH NPY mRNA and ARC galanin mRNA were unaltered by immobilization. Since NPY and galanin are considered orexigenic, while the POMC-melanocortin-4 receptor system is apparently anorexigenic, the changes in neuropeptide mRNAs and VMH CRHR-2 mRNA may play counterregulatory roles against anorectic CRH effects.

Full Text

Full text is available at the source.

View full text (PDF) ↗View full text ↗

Decreased Type 2 Corticotropin-Releasing Hormone Receptor mRNA Expression in the Ventromedial Hypothalamus during Repeated Immobilization Stress

Abstract

Full Text

You found one interesting study. We’ll send the next 7.

what lands in your inbox each week:

Recent issues from the glp-1 therapies brief

Abstract

Full Text

Related papers

You found one interesting study. We’ll send the next 7.

what lands in your inbox each week:

Recent issues from the glp-1 therapies brief