title: Ca²+ modulation in dorsal raphe plays an important role in NREM and REM sleep regulation during pentobarbital hypnosis.
abstract: Our previous studies indicated that L-type calcium channel blocker diltiazem could potentiate pentobarbital-induced hypnosis through serotonergic system. In view of the important role of dorsal raphe nucleus (DRN) on the sleep regulation and the pharmacological actions of calcium channel blocker, we presumed that Ca(2+) in the DRN may play an important role in sleep regulation in pentobarbital treated rats. Therefore, we investigated whether the Ca(2+) modulation in DRN by the microinjection of L-type Ca(2+) channel antagonist diltiazem, agonist BAY-K-8644, Ca(2+) chelator EGTA and CaCl(2) would alter the sleep parameters in pentobarbital treated rats. Results showed that perfusion of the agents attenuating Ca(2+) function, such as diltiazem (5 or 20 nmol) or EGTA (3 or 6 pmol) into DRN significantly increased pentobarbital (35 mg/kg, i.p.)-induced total sleep (TS), non-rapid eye movement (NREM) sleep and the slow wave sleep (SWS) ratio in NREM sleep. On the contrary, the DRN injection of the agents improving Ca(2+) function, such as BAY-K-8644 (10 nmol) or CaCl(2) (50 or 100 nmol) significantly reduced pentobarbital (35 mg/kg, i.p.)-induced TS, NREM sleep, rapid eye movement (REM) sleep and REM sleep ratio in TS without influence on SWS. These results suggested that the suppression of Ca(2+) function in DRN could increase NREM sleep including SWS, and the elevation of Ca(2+) function could reduce both NREM and REM sleep in pentobarbital treated rats.
authors.affiliation: Department of Pharmacology, Peking University, School of Basic Medical Science, 38 Xueyuan Road, Beijing 100191, China.
authors.forename: Su-Ying
authors.initials: SY
authors.lastname: Cui
authors.forename: Xiang-Yu
authors.initials: XY
authors.lastname: Cui
authors.forename: Juan
authors.initials: J
authors.lastname: Zhang
authors.forename: Zi-Jun
authors.initials: ZJ
authors.lastname: Wang
authors.forename: Bin
authors.initials: B
authors.lastname: Yu
authors.forename: Zhao-Fu
authors.initials: ZF
authors.lastname: Sheng
authors.forename: Xue-Qiong
authors.initials: XQ
authors.lastname: Zhang
authors.forename: Xiao-Lei
authors.initials: XL
authors.lastname: Shi
authors.forename: Yong-He
authors.initials: YH
authors.lastname: Zhang
mesh_terms: D000818:Animals; D002120:Calcium Channel Agonists; D002121:Calcium Channel Blockers / Q000494:pharmacology; D020013:Calcium Signaling / Q000502:physiology*; D004569:Electroencephalography; D004576:Electromyography; D006993:Hypnotics and Sedatives / Q000494:pharmacology; D008297:Male; D010424:Pentobarbital / Q000494:pharmacology*; D011903:Raphe Nuclei / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012890:Sleep / Q000187:drug effects* / Q000502:physiology*
chemical_list: D002120:Calcium Channel Agonists; D002121:Calcium Channel Blockers; D006993:Hypnotics and Sedatives; D010424:Pentobarbital