Interrelationship of thermal and sleep-wakefulness changes elicited from the medial preoptic area in rats.
The study investigated the possible interrelationship between changes in sleep-wakefulness and body temperature, primarily induced by manipulation of the noradrenergic system in the medial preoptic area. Saline, norepinephrine, and its alpha- and beta-blockers were injected in the medial preoptic area and in some control areas of rats, during their sleeping and active periods. 5-Hydroxytryptamine was injected in the medial preoptic area in another group of animals. Simultaneous changes in sleep-wakefulness and the body temperature were continuously recorded. Norepinephrine produced hypothermia and arousal, whereas alpha-adrenergic blockers induced hyperthermia and sleep. These changes in body temperature and in sleep-wakefulness did not follow an identical time course. 5-Hydroxytryptamine induced hyperthermia without affecting sleep-wakefulness. It is suggested that there are different neuronal mechanisms in the medial preoptic area that bring about the drug-induced changes in temperature and sleep-wakefulness.
Datta
S
S
Department of Physiology, All India Institute of Medical Sciences, New Delhi.
Kumar
V M
VM
Chhina
G S
GS
Singh
B
B
D000818:Animals; D001831:Body Temperature / Q000187:drug effects; D008297:Male; D009638:Norepinephrine / Q000494:pharmacology; D010643:Phenoxybenzamine / Q000494:pharmacology; D010646:Phentolamine / Q000494:pharmacology; D011301:Preoptic Area / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D012701:Serotonin / Q000494:pharmacology; D012894:Sleep Stages / Q000187:drug effects / Q000502:physiology*
D010643:Phenoxybenzamine; D012701:Serotonin; D009638:Norepinephrine; D010646:Phentolamine