[Effects of intraventricular injection of 5,7-dihydroxytryptamine on monoamines and sleep in the kitten (author's transl)].

Intraventricular injections of 5,7-DHT (.15 mg/g of brain weight) were performed in kittens aged 5 or 30 days. The neurotoxin induced a significant decrease of 5-HT and NA levels in the forebrain in both age groups, whereas a slight increase of each amine was observed respectively in the raphe and lateral brain stem of the younger group (Fig. 1). Pretreatment with desmethylimipramine (20 mg/kg I.P.) resulted in a protection of the noradrenergic system from the neurotoxin (Fig. 2). From the neurophysiological standpoint, 5,7-DHT induced a major paradoxical sleep (PS) insomnia in the one-month-old group, whereas no alteration of PS was observed in the younger group (Fig. 3). The DMI pre-treatment did not modify these results. The hypothesis of brain stem sprouting is discussed, and it is concluded that the serotoninergic system does not mediate the sleep regulation in the early post-natal period.