[Drug distribution during convulsive seizure in comparison with narcosis]

3 min after simultaneous i.v. administration of phenazone (200 mg/kg) and of pentetrazole (50 mg/kg) or of phenazone and of the convulsively active S-(+)-1-methyl-5-phenyl-5-propyl barbituric acid = (+)-MPPB (75 mg/kg), respectively, phenazone concentrations in liver, spleen and fat tissue of rats are lower, in brain tissue, however, it is higher than those of the control (rats receiving phenazone only); the distribution pattern of (+)-MPPB between the tissues corresponds to that of phenazone after simultaneous administration of pentetrazole. In rats anaesthetized by hexobarbital (35 mg/kg) or by the anaesthetically active R-(-)- 1-methyl-5-phenyl-5-propyl barbituric acid = (-)-MPPB (75 mg/kg), respectively, phenazone tissue distribution is at the same time (3 min) not different from that of the control; the tissue distribution pattern of (-)-MPPB corresponds to that of phenazone after simultaneous administration of hexobarbital. Following pretreatment with diazepam, reserpine and phenoxybenzamine, respectively, the tissue distribution pattern of (+)-MPPB, in the rats approaches that of (-)-MPPB. The distribution of (-)-MPPB in the tissues corresponds to that of (+)-MPPB, if the animals receive simultaneously pentetrazole or are electrically stimulated, respectively, to cause a convulsive seizure.