Effects of Decaserpine on the Electroencephalogram of Rabbit

Abstract

The dissociation between EEG and behavior produced by reserpine in rabbit was firstly demonstrated by Rinaldi and Himwich (1). Kikuchi (2) confirmed the result that the increase of the component of the resting waves in EEG at early period of reserpine action was followed by the arousal waves. He observed the appearance of the arousal waves of EEG in all of the animals which showed a clear-cut marked sedation during 4 to 10 hours after the administration of reserpine. He further showed that the pretreatment of rabbit with methamphetamine reversed the effect of reserpine on EEG. In the early period of reserpine action the EEG of rabbit showed an arousal pattern, and later it exhibited a pattern of the resting waves, which was observed within 10 hours or more after the administration.The pharmacological effects of decaserpine (10-methoxy deserpidine) have been reported by Mir and Lewis (3). Decaserpine did not produce sedation in a variety of animals and even large doses of decaserpine did not prolong barbiturate sleep in mice. The drug did not also produce ptosis or diarrhoea.However, when the initial blood pressure was considerably high in cat, the administration of decaserpine produced a gradual fall, and the same procedure depressed the pressor response elicited by electrical afferent stimulation of the cervical vagal nerve. The depletion of catecholamine in the brain, atrium and adrenal gland by the intravenous injection of decaserpine in rabbit has been shown by Higuchi et al. (4). The decrease of the level of brain noradrenaline was maximal about three hours after the injection. The duration of the depletion of brain noradrenaline produced by the intravenous injection of decaserpine was shorter than that produced by the sane pro cedure of reserpine. The decrease of the level of brain noradrenaline caused by decaserpine almost recovered twelve hours after the injection.The depletion of noradrenaline in brain shown by Higuchi et al. (4) urged strongly the present study of the effect of decaserpine on the spontaneous EEG in rabbit. METHODSAlbino rabbits, weighing 2.0 to 3.5 kg were used. After the animal had been anesthetized with ether and a tracheal cannula had been inserted, the skull of the

ELECTROENCEPHALOGRAPHIC STUDIES OF XYLOPININE, 2,3,10,11-TETR AMETHOX Y-5,6-13,13a-TETRAH YDRO-8-DIBENZO(a-g) QUINOLIZINE CITRATE IN RABBIT

“…The electroencephalographic studies of reserpine, decaserpine and tetrabenazine have been described elsewhere (5)(6)(7). Reserpine and decaserpine produced a biphasic response in unanesthetized rabbit.…”