Gadolinium blocks proton-activated currents in isolated Purkinje cells.

Patch-clamp and concentration jump studies showed that gadolinium ions dose-dependently reduced the amplitude of proton-activated currents (pH 6.5) in isolated Purkinje cells (gadolinium concentration producing a half-maximum effect was 69 microM for the peak and 8 microM for the stationary component of the current). The magnitude of the block did not depend on membrane potential at negative clamping potentials. Gadolinium blockade of activated receptor was more rapid and intensive in comparison with blocking of silent receptor.