Inhibitory effect of UK 14,304 on Δ[Ca2+]i. A, Recordings Δ[Ca2+]i before and during application of KCl (60 mM) in the absence and presence of UK 14,304 (1 μM) and CdCl2 (100 μM). UK 14,304 reduced Δ[Ca2+]i in both soma (upper traces) and a varicosity (lower traces). Δ[Ca2+]i evoked by KCl depolarization was blocked CdCl2. B, Pooled data from experiments similar to that shown in “A”. Control measurements made in individual soma or varicosities were set to a value of “1” and data obtained in the presence of UK 14,304 or CdCl2 were expressed as a fraction of that control value. Data are mean ± s.e.m. *indicates significantly different from Control (P <0.05). #indicates significantly different from measurements made in the presence of UK 14,304 (P <0.05).