Sleep induced by low doses of apomorphine in rats

doi:10.1016/0013-4694(79)90071-3

Electroencephalography and Clinical Neurophysiology

Volume 46, Issue 2, February 1979, Pages 214-219

https://doi.org/10.1016/0013-4694(79)90071-3 Get rights and content

Abstract

The effect of apomorphine on the EEG of freely moving rats was studied. Apomorphine at the dose of 1 mg/kg caused stereotypy and a marked reduction of total sleep. On the contrary, acute subcutaneous administration of apomorphine at the dose of 100 μg/kg, or less, markedly increased the amount of total sleep (corresponding mostly to synchronized sleep). Moreover, the infusion of apomorphine (80 μg/kg/h) for 4 h doubled the duration of slow and REM sleep.

The hypnotic effect of apomorphine was prevented by neuroleptics, such as pimozide, benzperidol and l-sulpiride, at doses which, per se, did not modify the EEG of the animals.

These results suggest the existence in the CNS of DA receptors mediating sleep.

Résumé

L'effet de l'apomorphine sur l'EEG de rats libres de leurs mouvements a été étudié pendant l'heure suivant le traitement. L'apomorphine á la dose de 1 mg/kg cause une stéréotypie et une réduction marquée du sommeil total. Au contraire, l'injection sous-cutanée aiguë d'apomorphine á la dose de 100 μg/kg, ou inférieure, a fortement augmenté la quantité de sommeil (correspondant surtout au sommeil lent). Par ailleurs, l'infusion d'apomorphine (80 μg/kg/h), pendant 4 h, a doublé la durée du sommeil lent et rapide. L'effet hypnotique de l'apomorphine a été empêché par des neuroleptiques tel que le pimozide, le benzpéridol et le l-sulpiride á des doses qui, par elles-mêmes, n'ont pas modifié l'EEG de l'animal. Les résultats indiquent l'existence, dans le SNC, de récepteurs dopaminergiques impliqués dans le sommeil.

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^☆: This investigation was supported by Tecnofarmaci S.p.A. Pomezia (Rome), Italy.

²: Present address: Institute of Physiology, Faculty of Medicine, L'Aquila, Italy.

³: Present address: Tecnofarmaci S.p.A., Pomezia (Rome), Italy.

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Sleep induced by low doses of apomorphine in ratsSommeil induit par petites doses d'apomorphine chez les rats☆

Abstract

Résumé

Europ. J. Pharmacol.

Electroenceph. clin. Neurophysiol.

Evidence for dopamine receptor stimulation by apomorphine

J. Pharm. Pharmacol.

Induzione di erezioni ripetute nel ratto adulto mediante apomorfina

Riv. Farm. Ter.

Receptor-mediated control of dopamine metabolism

Sedative hypnotic and antipsychotic effect of low doses of apomorphine in man

Evidence for dopamine receptors in the mouse brain mediating sedation

Nature (Lond.)