Hypophysectomy in monosodium glutamate-pretreated rats suppresses paradoxical sleep rebound.
Control untreated and pretreated female rats at birth with 10 injections of monosodium glutamate (MSG, 4 mg/g b. wt.) were hypophysectomized (HYPX) at 45-60 days of age and their sleep-waking cycle continuously registered. In control rats, hypophysectomy was followed by a 35.7% decrease in paradoxical sleep (PS) duration while it has no effect on the sleep of MSG-treated rats. After 24 h of PS deprivation, there was a normal immediate rebound of PS in the control HYPX and MSG rats while there was no significant rebound in the HYPX-MSG-treated rats. It is concluded that neuropeptides from arcuate nucleus and hypophysis are involved in a PS rebound mechanism.
Zhang
J X
JX
Laboratoire de Médecine Expérimentale, INSERM U52, C.N.R.S. UA1195, Université Claude Bernard, Lyon France.
Valatx
J L
JL
Jouvet
M
M
D000818:Animals; D005260:Female; D005971:Glutamates / Q000008:administration & dosage*; D007016:Hypophysectomy; D010902:Pituitary Gland / Q000502:physiology*; D051381:Rats; D012892:Sleep Deprivation / Q000502:physiology; D012895:Sleep, REM / Q000187:drug effects / Q000502:physiology*; D012970:Sodium Glutamate / Q000008:administration & dosage*
D005971:Glutamates; D012970:Sodium Glutamate