GLUTAMATERGIC NEURONS INVOLVED IN REM SLEEP REGULATION
Evidence that Neurons of the Sublaterodorsal Tegmental Nucleus Triggering Paradoxical (REM) Sleep Are Glutamatergic
Olivier Clément, MSc1,2; Emilie Sapin, PhD1,2,3,4; Anne Bérod, PhD1,2,5; Patrice Fort, PhD1,2; Pierre-Hervé Luppi, PhD1,2
1Physiopathology of the Neuronal Network Responsible for the Sleep-Waking Cycle Team, CNRS UMR5292; INSERM U1028; Lyon Neuroscience Research Center, Lyon, F-69372, France
; 2Université Lyon 1, Université de Lyon, Lyon, F-69000, France
; 3INSERM U1042, Grenoble, F-38043, France
; 4Université de Grenoble, U 1042, Grenoble, F-38043, France
; 5CNRS, EAC5006, Pharmacologie et Imagerie de la Neurotransmission Sérotoninergique, Lyon, France
To determine whether sublaterodorsal tegmental nucleus (SLD) neurons triggering paradoxical (REM) sleep (PS) are glutamatergic.
Three groups of rats were used: controls, rats deprived of PS for 72 h, and rats allowed to recover for 3 h after deprivation. Brain sections were processed for double labeling combining Fos immunohistochemistry and vesicular glutamate transporter 2 (vGLUT2) in situ hybridization.
Measurements and Results:
The number of single Fos+ and Fos/vGLUT2+ double-labeled neurons was counted for each experimental condition. A very large number of Fos+ neurons expressing vGLUT2 mRNA specifically after PS hypersomnia was counted in the SLD. These double-labeled cells accounted for 84% of the total number of Fos+ cells.
This finding adds further evidence to the concept that PS-on neurons of the SLD generating PS are of small size and glutamatergic in nature. By means of their descending projections to medullary and/or spinal glycinergic/GABAergic premotoneurons, they may be especially important for the induction of muscle atonia during PS, a disturbed phenomenon in narcolepsy and REM sleep behavior disorder.
Clément O; Sapin E; Bérod A; Fort P; Luppi PH. Evidence that neurons of the sublaterodorsal tegmental nucleus triggering paradoxical (REM) sleep are glutamatergic. SLEEP 2011;34(4):419-423.