Lateral preoptic lesions void slow-wave sleep enhanced by uridine but not by muramyl dipeptide in rats.
We investigated the site of action of two sleep-inducing substances, viz., muramyl dipeptide (MDP) and uridine. Localized electrolytic lesions were made bilaterally in the lateral preoptic hypothalamus (LPO) in rats and nocturnal 10-h i.c.v. infusions of MDP and uridine were performed before and after the LPO lesions. MDP increased only slow-wave sleep (SWS) in both intact and LPO-lesioned rats. Uridine promoted both SWS and paradoxical sleep (PS) before the LPO lesions whereas it increased only PS after the lesions. These results suggest that the LPO is crucial for SWS-promoting action of uridine but not MDP.
Kimura-Takeuchi
M
M
Institute of Medical and Dental Engineering, Tokyo Medical and Dental University, Japan.
Inoué
S
S
D000119:Acetylmuramyl-Alanyl-Isoglutamine / Q000494:pharmacology*; D000818:Animals; D001831:Body Temperature / Q000187:drug effects; D001921:Brain / Q000187:drug effects / Q000502:physiology; D007276:Injections, Intraventricular; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D011301:Preoptic Area / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012890:Sleep / Q000187:drug effects / Q000502:physiology*; D012895:Sleep, REM / Q000187:drug effects; D014529:Uridine / Q000494:pharmacology*; D014851:Wakefulness / Q000187:drug effects
D000119:Acetylmuramyl-Alanyl-Isoglutamine; D014529:Uridine