Electroencephalographic and autonomic effects of centrally administered neurotensin in the rabbit.

Neurotensin perfusion into the third ventricle of the unanesthetized rabbit induces an increase of the total power density spectrum of the cortex, without modifying the electrical activity of the cornu Ammonis dorsale. This evidence suggests a direct action of the peptide on the cortical neurons and seems to exclude the involvement of the brainstem reticular formation in inducing the electroencephalographic pattern. Simultaneously Neurotensin produces an evident behavioural excitation and a moderate thermolytic effect. The electroneurophysiologic, autonomic and behavioural changes are independent from one another and seem to depend on an action exerted by Neurotensin at various levels in the CNS.