COMPARATIVE ELECTROPHYSIOLOGICAL ASPECTS OF ALUMINUM ACTIONS ON CENTRAL NEURONS AND NEURONAL SYNAPSES OF INVERTEBRATE AND VERTEBRATE ANIMALS

Aluminum compounds (Al) increased the membrane potential (Em) and decr eased the input resistance (Rin) of identified snail neurons. The neur onal excitability increased after Al withdrawal in the washing period. Cumulative Al applications ca used dose-dependent modulation of Em an d Rin in most of the studied neurons. Two phase actions were recorded on stimulus evoked excitatory postsynaptic potentials (EPSPs) or curre nts (EPSCs) at pH 6.5-6.9. The Al induced facilitation followed by att enuation were statistically significant, time- and dose-dependent even ts. They could be recorded at each Em. Low affinitiy and slow binding kinetics could characterize the Al actions on the neurons. Al showed p H- dependent suppression of EPSPs or EPSCs in some neurons. Our findin gs are partially comparable with A I induced electrophysiological and pharmacological modifications reported on vertebrate neurons. (C) 1998 Inter Press, Inc.