REPETITIVE HYPOXIC EXPOSURE OF BRAIN-SLICES AND ELECTROPHYSIOLOGICAL RESPONSES AS AN EXPERIMENTAL-MODEL FOR INVESTIGATION OF CEREBROPROTECTIVE MEASUREMENTS

An in vitro hippocampal (CA-1 region, guinea pig) slice technique usin g repeated hypoxia was employed to model electrophysiological changes (DC-potentials and evoked potentials (EP) by stimulation of Schaffer-c ollaterals) occurring in the hypoxic CA1 pyramidal layer. A standardiz ed neuronal response under repeated hypoxic conditions was observed in this model, consisting of disappearance of EP and a trend towards par tially reversible, but progressive synaptic failure subsequent anoxic depolarisation (AD). Slices treated with the calcium antagonist nimodi pine showed a prolongation of AD latency between the first and followi ng hypoxias. So it seems possible to simulate hypoxic lesions of the b rain tissue by using this in vitro slice model.