Urocortin I (UCN I) is a structural analogue of corticotropin-releasing factor (CRF), which, together with arginine-vasopressin (AVP), are the principle adrenocorticotropic hormone (ACTH) secretagogues in mammals. The aim of the present study was to investigate the effects of UCN I on the hypothalamic CRF and AVP concentration and its impact on the hypothalamic-pituitary-adrenal (HPA) axis. First, male Wistar rats were injected intracerebroventricularly (ICV) with 0.5, 1, 2 and 5 μg of UCN I. After 30 min hypothalamic CRF and AVP concentrations were determined by immunoassays. In parallel, the trunk blood was collected and plasma ACTH and corticosterone concentration was determined by ELISA and chemofluorescent assay, respectively. Second, rats were pretreated ICV with selective antagonists of receptors being implicated in the regulation of the HPA axis (0.1 μg antalarmin for CRFR1, 1 μg astressin 2B for CRFR2 or 0.1 μg deamino-Pen1,Tyr2,Arg8-vasopressin for AVPR3) and treated ICV with the most effective dose of UCN I (5 μg). After 30 min plasma corticosterone concentration was determined by chemofluorescent assay. UCN I induced dose-dependent augmentation of the hypothalamic CRF and AVP concentration, associated with dose-dependent elevation of the plasma ACTH and corticosterone concentration. The most significant effect of UCN I on the plasma corticosterone concentration was inhibited by antalarmin, but was not influenced by astressin 2B or deamino-Pen1,Tyr2,Arg8-vasopressin. The present study demonstrates that UCN I modulates the concentration of the hypothalamic ACTH secretagogues in parallel with the concentration of the plasma ACTH and corticosterone. Our results suggest that UCN I may activate the HPA axis by stimulation of the hypothalamic CRF production, and this process is mediated by CRFR1, and not by CRFR2. UCN I may stimulate the AVP production, as well, but, based on the results with AVPR3 antagonist, this effect is not involved in the regulation of the HPA axis.
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http://dx.doi.org/10.1016/j.npep.2013.11.002 | DOI Listing |
Neuropeptides
January 2025
Department of Pathophysiology, Faculty of Medicine, University of Szeged, Hungary.
Corticotropin-releasing factor (CRF) and urocortins (UCN1, UCN2 and UCN3) belong to the same CRF family of neuropeptides. They regulate the neuroendocrine, autonomic and behavioral responses to stress via two CRF receptors (CRF1 and CRF2). Stress, anxiety and depression affects the activity of the hypothalamic-pituitary-adrenal (HPA) axis and the serotoninergic neurotransmission, both being regulated by CRF and CRF-related peptides.
View Article and Find Full Text PDFNeuroscience
February 2025
Guangdong Provincial Key Laboratory of Animal Nutrition Control, South China Agricultural University, Guangzhou, Guangdong 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong 510642, China. Electronic address:
Corticotropin-releasing factor (CRF) is an important stress hormone, and because of the different distributions and functions of its receptors, CRF has various effects on the stress response of animals. CRF receptor 2 (CRFR2) is a functional receptor of CRF that may be related to appetite regulation and sex differences. In this study, male and female C57BL/6 mice were exposed to an ambient temperature of 4 °C, and feed intake were determined.
View Article and Find Full Text PDFSci Rep
December 2024
Department of Neuroscience and Cell Biology, Osaka University Graduate School of Medicine, Osaka, 565-0871, Japan.
This study investigated the impact of multiple nerve block methods (local anesthesia, conventional radiofrequency thermocoagulation [CRF], and pulsed radiofrequency [PRF]) on thermoregulation. Focusing on hypothalamic function, the effects of local anesthesia, CRF, and PRF on central and peripheral temperatures were analyzed and compared. Our findings revealed that all three nerve block groups cause a decrease in central temperature, with the CRF group exhibiting the most pronounced effect.
View Article and Find Full Text PDFJ Affect Disord
December 2024
Experimental Therapeutics and Pathophysiology Branch, Intramural Research Program, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA. Electronic address:
Background: Subanesthetic doses of (R,S)-ketamine (ketamine) have demonstrated rapid and robust antidepressant effects in individuals with depression. However, individual variability in response to ketamine exists, and current biomarkers of ketamine treatment response are not entirely understood. Preclinical evidence suggests a link between hypothalamic-pituitary-adrenal (HPA) axis activation, a determinant of the stress response system, and ketamine's efficacy in stressed mice exhibiting enhanced antidepressant responses.
View Article and Find Full Text PDFBiol Psychiatry Glob Open Sci
January 2025
Department of Psychology and Neuroscience, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.
Background: Binge alcohol drinking is a dangerous behavior that can contribute to the development of more severe alcohol use disorder. Importantly, the rate and severity of alcohol use disorder has historically differed between men and women, suggesting that there may be sex differences in the central mechanisms that modulate alcohol (ethanol) consumption. Corticotropin-releasing factor (CRF) is a centrally expressed neuropeptide that has been implicated in the modulation of binge-like ethanol intake, and emerging data highlight sex differences in CRF systems.
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