VESICULAR ACETYLCHOLINE TRANSPORT INHIBITOR SUPPRESSES REM-SLEEP

THE vesamicol-like compound (+/-)-4-aminobenzovesamicol (ABV) non-comp etitively inhibits vesicular packaging of acetylcholine (ACh) in presy naptic terminals. This study tested the hypothesis that microinjection of ABV into the medial pontine reticular formation (mPRF) of intact, unanesthetized cats would inhibit rapid eye movement (REM) sleep. Micr oinjection of ABV alone or before administration of the acetylcholines terase inhibitor neostigmine was used to evaluate the effects of ABV o n natural REM sleep and on the neostigmine-induced REM sleep-like stat e. ABV decreased (24.8%) REM sleep and significantly reduced (33.6%) t he neostigmine-induced REM sleep-like state. The results show for the first time that REM sleep generation can be disrupted by blocking a sy naptic vesicle protein that modulates ACh transport in localized regio ns of the mPRF.