Research Article

Mu Opioid Agonistic Effect on Neuropeptide Gene Expression Levels Involved in Hypothalamic Feeding Regulation

Volume: 6 Number: 1 January 31, 2025
EN TR

Mu Opioid Agonistic Effect on Neuropeptide Gene Expression Levels Involved in Hypothalamic Feeding Regulation

Abstract

Background: The regulation of food intake in the hypothalamus is one of most complicated through the integration of various neuroendocrine mechanisms. In this region, orexigenic and anorexigenic peptides play a role by responding to different stimuli. Additionally, central opioidergic systems are involved in the regulation of feeding behavior. Several neuropeptides expressed in the hypothalamus also contribute to the regulation of food intake. The aim of this study was to investigate the effects of mu opioidergic agonist/antagonist molecules on both orexigenic and anorexigenic peptides gene expression levels in the hypothalamus. Methods: In our study, 48 male Wistar Albino rats were divided into 4 groups as control, morphine, naloxone and morphine+naloxone. The control group received subcutaneous SF solution for 5 days; morphine group received morphine at a dose of 10 mg/kg/day for 5 days; naloxone group SF was administered for 5 days and naloxone at a dose of 3 mg/kg 1.5 hours after the last injection: morphine+naloxone group received naloxone 1.5 hours after 5 days of morphine injection. Hypothalamus tissues were isolated from brains at the end of experimental period. Anorexigenic and orexigenic peptide expression levels were analysed by RT-PCR method. Differences between groups were statistically analyzed using one-way factorial ANOVA and Tukey post-hoc test. Results: Morphine administration results in a decrease in the expression levels of OX2R and LepR genes, but did not change ORXA, OX1R, AgRP, NPY, POMC gene expression. Naloxone administration increased AgRP and NPY expression while decreasing OX2R, LepR and APLNR gene expression levels. Conclusions: Our findings suggest that morphine may affect the gene expression of molecules related to regulation of nutrition and metabolism in the hypothalamus. Further studies are needed to clarify the possible mechanistic effects of mu opiodergic activity on the central control of feeding in morphine dependence manner.

Keywords

AgRP , apelin , hypothalamus , neuropeptides , NPY , morphine dependence , POMC , rat

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APA
Karakaya Cimen, F. B., Erkaya Turan, Z., Sen, A., Caliskan Sak, K. Z., Eroglu Günes, C., Kurar, E., Cimen, Y. A., & Kutlu, S. (2025). Mu Opioid Agonistic Effect on Neuropeptide Gene Expression Levels Involved in Hypothalamic Feeding Regulation. Archives of Current Medical Research, 6(1), 1-7. https://doi.org/10.47482/acmr.1608775