Ghrelin, an endogenous ligand for the GHS receptor, stimulates GH secretion and gastrointestinal motility and has orexigenic effects. In this study, the relationships between ghrelin, GH secretion, feeding behavior, and sleep-wake patterns were investigated in adult male rats. The half-life of exogenous ghrelin (10 microg i.v.) in plasma was about 30 min. Repeated administration of ghrelin at 3- to 4-h intervals (one during lights-on and two during lights-off periods) increased GH release and feeding activity, and decreased rapid eye movement sleep duration. Endogenous plasma ghrelin levels exhibited pulsatile variations that were smaller and less regular compared with those of GH. No significant correlation between GH and ghrelin circulating levels was found, although mean interpeak intervals and pulse frequencies were close for the two hormones. In contrast, ghrelin pulse variations were correlated with food intake episodes in the lights off period, and plasma ghrelin concentrations decreased by 26% in the 20 min following the end of the food intake periods. A positive correlation between ghrelin levels and active wake was found during the first 3 h of the dark period only. In conclusion, ghrelin, in addition to affecting GH secretion, gastrointestinal motility, and feeding activity, also modifies sleep-wake patterns. However, a direct action of ghrelin per se or the indirect effects of feeding (and all of its attendant metabolic sequelae) on sleep cannot be differentiated. Moreover, ghrelin secretion is pulsatile and directly related to feeding behavior only.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1210/endo.143.4.8712 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Effect of long-term negative energy on appetite hormone levels in individuals with prediabetes and diabetes.
Rev Assoc Med Bras (1992)
January 2025
Yalova University, Faculty of Medicine, Department of Medical Biochemistry, AD - Yalova, Turkey.
Objective: Calorie restriction and exercise are commonly used first interventions to prevent the progression of prediabetes and alleviate the symptoms of type 2 diabetes. Our study was designed to determine the effect of the energy deficit caused by long-term (12-week) calorie restriction and exercise programs on appetite responses in obese individuals with prediabetes and type 2 diabetes.
Methods: Calorie restriction and exercise programs appropriate for age, gender, and work environment were applied to 22 individuals with prediabetes and 22 with type 2 diabetes participating in the study for a period of 12 weeks.
Intranasal delivery of a ghrelin mimetic engages the brain ghrelin signalling system in mice.
Endocrinology
January 2025
Department of Physiology/Endocrine, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Sweden.
Ghrelin, the endogenous ligand of the growth hormone secretagogue receptor (GHSR), promotes food intake, other feeding behaviours and stimulates growth hormone (GH) release from the pituitary. Growth hormone secretagogues (GHS), such as GHRP-6 and MK-0677, are synthetic GHSR ligands that activate orexigenic Neuropeptide Y neurons that co-express Agouti-Related Peptide (AgRP) in the arcuate nucleus of the hypothalamus when administered systemically. Systemic GHRP-6 also stimulates GH release in humans and rats.
View Article and Find Full Text PDFDecoding the role of ghrelin and its interactions with central signaling pathways in avian appetite regulation.
Vet Res Commun
January 2025
Department of Biology, Faculty of Basic Science, Central Tehran Branch, Islamic Azad University, Tehran, Iran.
Ghrelin, a peptide hormone primarily produced in the enteroendocrine cells of the gastrointestinal tract, plays a vital role in regulating food intake, and energy balance in avian species. This review examines the complex interactions between ghrelin and the central signaling pathways associated with hunger regulation in birds. In contrast to mammals, where ghrelin typically promotes feeding behavior, its effects in birds appear more nuanced, exhibiting anorexigenic properties under certain conditions.
View Article and Find Full Text PDFReal-time detection of somatostatin release from single islets reveals hypersecretion in type 2 diabetes.
Acta Physiol (Oxf)
February 2025
Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden.
Aim: Somatostatin from pancreatic δ-cells is a paracrine regulator of insulin and glucagon secretion, but the release kinetics and whether secretion is altered in diabetes is unclear. This study aimed to improve understanding of somatostatin secretion by developing a tool for real-time detection of somatostatin release from individual pancreatic islets.
Methods: Reporter cells responding to somatostatin with cytoplasmic Ca concentration ([Ca]) changes were generated by co-expressing somatostatin receptor SSTR2, the G-protein Gα15 and a fluorescent Ca sensor in HeLa cells.
Ghrelin Induces Ferroptosis Resistance and M2 Polarization of Microglia to Alleviate Neuroinflammation and Cognitive Impairment in Alzheimer's Disease.
J Neuroimmune Pharmacol
January 2025
Pharmacy Department, Baotou Central Hospital, Baotou, 014040, Inner Mongolia, China.
Microglial polarization and ferroptosis are important pathological features in Alzheimer's disease (AD). Ghrelin, a brain-gut hormone, has potential neuroprotective effects in AD. This study aimed to explore the potential mechanisms by which ghrelin regulates the progression of AD, as well as the crosstalk between microglial polarization and ferroptosis.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!