title: Reversal of the sleep-wake cycle by heroin self-administration in rats.
abstract: The goal of this study was to examine how heroin self-administration, abstinence, and extinction/reinstatement affect circadian sleep-wake cycles and the associated sleep architecture. We used electroencephalography (EEG) and electromyography (EMG) to measure sleep patterns in male Sprague-Dawley rats over 16 trials of heroin self-administration (acquisition), 14 days of abstinence, and a single day of extinction and drug-induced reinstatement. Rats self-administering heroin showed evidence of reversed (diurnal) patterns of wakefulness, non-rapid eye movement (NREM) sleep, and rapid eye movement (REM) sleep throughout acquisition. During abstinence, their wake and NREM sleep patterns were immediately restored to the normal nocturnal distribution. REM patterns remained inverted for the first 3-6 days of abstinence in heroin self-administering rats. The single extinction/reinstatement test was without effect. These data suggest that heroin may have the ability to affect circadian distribution of sleep and wakefulness, either indirectly, where animals shift their sleep-wake cycle to allow for drug taking, or directly, through wake-promoting actions or actions at circadian oscillators in the brain.
authors.affiliation: Department of Neural and Behavioral Sciences, The Pennsylvania State University, College of Medicine, 500 University Drive, H181, Hershey, PA 17033, USA. Electronic address: aac5186@psu.edu.
authors.forename: Alissa A
authors.initials: AA
authors.lastname: Coffey
authors.affiliation: Department of Psychiatry, The Pennsylvania State University College of Medicine, 500 University Drive, H073, Hershey, PA 17033, USA. Electronic address: zguan@hmc.psu.edu.
authors.forename: Zhiwei
authors.initials: Z
authors.lastname: Guan
authors.affiliation: Department of Neural and Behavioral Sciences, The Pennsylvania State University, College of Medicine, 500 University Drive, H181, Hershey, PA 17033, USA. Electronic address: psg6@psu.edu.
authors.forename: Patricia S
authors.initials: PS
authors.lastname: Grigson
authors.affiliation: Department of Psychiatry, The Pennsylvania State University College of Medicine, 500 University Drive, H073, Hershey, PA 17033, USA. Electronic address: jfang@hmc.psu.edu.
authors.forename: Jidong
authors.initials: J
authors.lastname: Fang
mesh_terms: D000818:Animals; D001921:Brain / Q000502:physiology; D002940:Circadian Rhythm / Q000187:drug effects*; D004569:Electroencephalography / Q000187:drug effects; D003932:Heroin / Q000009:adverse effects* / Q000378:metabolism / Q000494:pharmacology; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D012890:Sleep / Q000187:drug effects*; D012895:Sleep, REM / Q000187:drug effects; D014851:Wakefulness / Q000187:drug effects
chemical_list: D003932:Heroin
keywords: Circadian rhythm; EEG; EMG; Heroin; Self-administration; Sleep-wake