Cholinergically induced REM sleep triggers Fos-like immunoreactivity in dorsolateral pontine regions associated with REM sleep.
We sought to determine the presence of Fos-like immunoreactive (Fos-LI) cells in the pontine brainstem following cholinergically induced sustained rapid-eye movement (REMc) sleep in cats. Microinjections (0.25 microliter) of vehicle (N = 2) or carbachol (2.0 micrograms/0.25 microliter; N = 4) were made into the medial pontine reticular formation. Carbachol produced a state with all the signs of natural REM sleep and with durations of 15.2-57.8 min. Compared with vehicle control animals, carbachol treated animals showed a significantly higher number of Fos-LI cells in pontine regions implicated in REM sleep generation, with longer REMc bouts associated with more Fos-LI cells than the short-duration bout. Regions with REMc-associated Fos-LI increases included: the lateral dorsal tegmental (LDT) and pedunculopontine tegmental (PPT) nuclei, where some Fos-LI cells were immunohistochemically identified as cholinergic; the locus coeruleus, where some of the Fos-LI cells were identified to be catecholaminergic; the dorsal raphe and the pontine reticular formation. These findings suggest immediate early gene activation is associated with the ubiquitous biological state of REM sleep.
Shiromani
P J
PJ
Veterans Administration Medical Center, Brockton, MA 02401.
Kilduff
T S
TS
Bloom
F E
FE
McCarley
R W
RW
D000109:Acetylcholine / Q000494:pharmacology*; D000818:Animals; D002217:Carbachol / Q000494:pharmacology; D002415:Cats; D015870:Gene Expression / Q000502:physiology*; D016762:Genes, fos / Q000235:genetics*; D011149:Pons / Q000737:chemistry / Q000187:drug effects*; D016760:Proto-Oncogene Proteins c-fos / Q000032:analysis*; D012895:Sleep, REM / Q000187:drug effects / Q000502:physiology*
D016760:Proto-Oncogene Proteins c-fos; D002217:Carbachol; D000109:Acetylcholine