Evidence for Electrical Coupling in the SubCoeruleus (SubC) Nucleus.
SubCoeruleus (SubC) neurons, which are thought to modulate rapid-eye-movement (REM) sleep, were recorded in brain stem slices from 7- to 20-day rats and found to manifest spikelets, indicative of electrical coupling. Spikelets occurred spontaneously or could be induced by superfusion of the cholinergic agonist carbachol. Whole cell recordings revealed that carbachol induced membrane oscillations and spikelets in the theta frequency range in SubC neurons in the presence of fast synaptic blockers. Electrical coupling in neurons is mediated by the gap junction protein connexin 36 (Cx 36). We found that Cx 36 gene expression and protein in the mesopontine tegmentum decreased during development. Cx 36 protein levels specifically in the SubC decreased in concert with the developmental decrease in REM sleep. The presence of electrical coupling in the SubC introduces a novel potential mechanism of action for the regulation of sleep-wake states.
Heister
David S
DS
Center for Translational Neuroscience, Dept. of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, 4301 W. Markham St., Slot 847, Little Rock, AR 72205, USA.
Hayar
Abdallah
A
Charlesworth
Amanda
A
Yates
Charlotte
C
Zhou
Yi-Hong
YH
Garcia-Rill
Edgar
E
D000200:Action Potentials / Q000187:drug effects / Q000502:physiology; D000818:Animals; D001710:Biotin / Q000031:analogs & derivatives / Q000096:biosynthesis / Q000235:genetics; D017630:Connexins / Q000096:biosynthesis / Q000235:genetics; D004594:Electrophysiology; D019706:Excitatory Postsynaptic Potentials / Q000502:physiology; D005260:Female; D005456:Fluorescent Dyes; D007546:Isoquinolines; D008125:Locus Coeruleus / Q000166:cytology / Q000502:physiology*; D008564:Membrane Potentials / Q000502:physiology; D009474:Neurons / Q000502:physiology; D018408:Patch-Clamp Techniques; D011247:Pregnancy; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D051381:Rats; D017207:Rats, Sprague-Dawley; D012154:Reticular Formation / Q000502:physiology; D012890:Sleep / Q000502:physiology; D014851:Wakefulness / Q000502:physiology; D000097004:Gap Junction delta-2 Protein
D001710:Biotin; D017630:Connexins; D005456:Fluorescent Dyes; D007546:Isoquinolines; D012333:RNA, Messenger; D000097004:Gap Junction delta-2 Protein; C070614:neurobiotin; C017475:lucifer yellow