Brownian dynamics were simulated for the simple model of calcium channels introduced by Nonner and Eisenberg, computing electric forces from all charges. Permanent charge (of acidic side chains) was varied. Substantial conduction was found only at certain discrete values of permanent charge. Different con-duction states had different selectivity, one resembling L-type CaV1 and the other RyR channels. We speculate that thermally acti-vated switching between conductance values could produce some types of spon-taneous gating. Below is calcium current J as a function of permanent charge Qf and calcium concentration.