The effects of low calcium and background light on the sensitivity of toad rods

AUTOR(ES)

Bastian, Bruce L.

RESUMO

1. We have examined the effects of decreases in extracellular Ca2+ concentration on the intracellularly recorded light responses of rods from the toad, Bufo marinus. In agreement with previous results (Brown & Pinto, 1974; Lipton, Ostroy & Dowling, 1977), Ca2+ concentrations below 10-6 M produced a depolarization of rod resting membrane potential of approximately 30-40 mV and a corresponding increase in the maximum amplitude of the rod's light responses, so that saturating flashes in normal and low Ca2+ Ringer produced hyperpolarizations to approximately the same membrane potential.

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