Reversible Change of Extracellular pH at the Generation of Mechano-Induced Electrical Reaction in a Stem of Cucurbita pepo.

As was shown recently the generation of cooling-induced action potential accompanies the reversible change of extracellular pH.1 The pH changes are linked to the Ca(2+)-induced transient inhibition of the plasma membrane H(+)-ATPase. Generation of mechano-induced local bioelectrical reaction (LBER) also accompanies the reversible change of extracellular pH. Shifts of pH medium during generation of mechano-induced electrical impulse are less than during generation of cooling-induced bioelectrical response. The exclusion of Ca(2+) influx from extracellular stores don't decrease the amplitude of mechano-induced LBER.