Melatonin modulate the expression of α1- and β2-adrenoceptors in the hippocampus of rats subjected to unpredictable chronic mild stress

Abstract

OBJECTIVE: This study investigated the effects of chronic melatonin treatment on gene expression of α1-, α2-, β1- and β2-adrenoceptors in the hippocampus of rats subjected to chronic unpredictable mild stress (CUMS). BACKGROUND: Preclinical studies have also shown that melatonin prevented short- and long-term memory impairments and exhibited antidepressant-like actions. METHODS: For this study, we used 24 animals, which were divided into four groups, and the experiment lasted 4 weeks. We quantifi ed the changes in mRNA and protein levels of α1-, α2-, β1- and β2-adrenoceptors in the hippocampus after melatonin treatment. RESULTS: Our results demonstrated a decreased gene expression of α1-, α2- and β2-adrenoceptors in the hippocampus of rats subjected to unpredictable chronic mild stress, while there was no change in gene expression of β1-adrenoceptors. Melatonin treatment in the CUMS rats prevented the stress-induced decrease in mRNA and protein levels of α1-and β2-adrenoceptors, whereas did not affect either on mRNA or protein level of β1-and α2-adrenoceptors. CONCLUSION: Our data suggest that melatonin, by increasing reduced levels of α1- and β2-adrenoceptors mRNA and protein in the hippocampus of chronic stressed rats, may be benefi cial in conditions such as chronic stress and provides an experimental opportunity to probe into further molecular mechanisms underlying the regulation of these receptor subtype.