Chronic ethanol consumption impairs the circadian rhythm of pro-opiomelanocortin and period genes mRNA expression in the hypothalamus of the male rat.
Certain psychiatric disorders are known to alter the body's biological rhythms. However, currently, very little information is known about the effect of chronic ethanol administration on the circadian clock or the rhythm of beta-endorphin-containing neurons that participate in the control of the reward and reinforcement of alcohol drinking. Here, we report that administration of ethanol, via a liquid diet paradigm for a period of 2 weeks, abolishes the circadian rhythm of pro-opiomelanocortin mRNA expression of beta-endorphin neurons in the arcuate nucleus of the hypothalamus. The circadian expression of the clock governing rat period genes (rPeriod1 mRNA and rPeriod2 mRNA) in the arcuate nucleus was significantly altered, suggesting that ethanol administration disrupted the internal clock. Moreover, ethanol consumption altered the circadian rhythms of rPeriod2 and rPeriod3 mRNA levels in the suprachiasmatic nucleus, suggesting that ethanol also affected the function of the central pacemaker. Our findings identified the vulnerability of the body's clock machinery and its opioidergic system to chronic alcohol drinking.
Endocrine Program, Center of Alcohol Studies and Department of Animal Sciences, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08901-8525, USA.
Cui Ping
CP
Chen
Peter
P
Kuhn
Juan P
JP
Advis
Dipak K
DK
Sarkar
D020268:Alcohol-Induced Disorders, Nervous System / Q000139:chemically induced / Q000378:metabolism / Q000503:physiopathology; D000818:Animals; D001111:Arcuate Nucleus of Hypothalamus / Q000187:drug effects / Q000378:metabolism; D018797:Cell Cycle Proteins; D021081:Chronobiology Disorders / Q000139:chemically induced* / Q000378:metabolism / Q000503:physiopathology; D002940:Circadian Rhythm / Q000187:drug effects; D000431:Ethanol / Q000494:pharmacology*; D005786:Gene Expression Regulation / Q000187:drug effects*; D007031:Hypothalamus / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D009687:Nuclear Proteins / Q000235:genetics*; D056950:Period Circadian Proteins; D011333:Pro-Opiomelanocortin / Q000235:genetics*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D013493:Suprachiasmatic Nucleus / Q000187:drug effects / Q000378:metabolism; D014157:Transcription Factors
D018797:Cell Cycle Proteins; D009687:Nuclear Proteins; C539023:Per1 protein, mouse; C539024:Per1 protein, rat; C513312:Per2 protein, mouse; C513311:Per2 protein, rat; C512645:Per3 protein, mouse; C512646:Per3 protein, rat; D056950:Period Circadian Proteins; D012333:RNA, Messenger; D014157:Transcription Factors; D000431:Ethanol; D011333:Pro-Opiomelanocortin