FIGURE 2.

Micromolar Ca²⁺ stimulates CA-NSC activity immediately after patch excision. (A) CA-NSC channel activity elicited by excision of a patch into 6 μM Ca²⁺. Note an approximately twofold increase in P_o upon depolarization from −40 to +40 mV. Subsequent application of saturating [Ca²⁺] activated ∼25 channels in this patch. (B) Half-maximal activation of three CA-NSC channels in a patch excised into ∼20 μM Ca²⁺. (C) Maximal activation of eight CA-NSC channels in a patch excised into 100 μM Ca²⁺. Bars indicate changes in bath [Ca²⁺], membrane potential was −40 mV in B and C.