The effect of syrosingopine on spontaneous EEG and EEG arousal induced by external stimuli in rabbits

Abstract

In 46 rabbits the electroencephalographic effects of syrosingopine were correlated with biogenic amines in brain and heart. A low dose (0.3 mg/kg) of this drug preferentially depleted cardiac amines as opposed to brain amines 1, 5 and 24 hours after injection. No increases in the duration of spontaneous EEG arousal patterns were observed. On the contrary, the duration of EEG arousal and the arterial pressor responses to external stimuli were diminished. Such a result suggests that peripheral sympathetic transmitter participates in part in maintaining EEG arousal reaction. A high dose (10 mg/kg) of syrosingopine produced marked depletions of brain and cardiac amines, associated with an increase in the duration of EEG alerting 1 hour after administration. After 5 hours, the duration of spontaneous EEG arousal was significantly less than that in the controls. These observations indicate that both syrosingopine and reserpine produce EEG alerting during the time when brain amines are being liberated and the peripheral release of amines is of less consequence in the generation of EEG arousal patterns after these drugs.