Figure 4. Effect of U46619 and L-cis-diltiazem on [Ca²⁺]_i in the primary cultured aortic smooth muscle cells.

Cells were pretreated with 300 nM nifedipine to block L-type Ca²⁺ channels. A, B. Representative fluorescence images of cultured smooth muscle cells before (A) and after (B) 100 nM U46619. C. Summary of data showing the inhibitory effect of L-cis-diltiazem (100 nM) on U46619-induced [Ca²⁺]_i rises. Shown were the percentage of cells displaying U46619-induced [Ca²⁺]_i rises before and after U46619 challenge, Mean ± SE (n = 5). * p<0.05 as compared with the control.