VOLTAGE-DEPENDENT EFFECT OF AL3-NEURONS( ON CHANNEL ACTIVITIES IN HIPPOCAMPAL)

The effects of Al3+ on Na+ and K+ channel activities in rat and rabbit hippocampal neurons have been examined. Al3+ mediated a pronounced vo ltage-dependent inhibition of single Na+ channel activities in inside- out patches excised from neuronal membranes. The reduction in channel activity was more substantial under defined conditions, particularly w hen changing the holding potential from -120 to -80 mV. This voltage-d ependent block indicates that Al3+ can mainly inhibit the excitation o f neurons with less negative resting potentials. The observed effect m ay be related to the pathogenetic mechanism of the specific action of Al3+ on defined types of neurons affected in neurodegenerative disorde rs such as Alzheimer's disease. (C) 1997 Academic Press.