Reduced expression of L-type Ca²⁺ channels in Dicer KO bladder.

Panel A shows contractile responses to 60 mM K⁺ and 3 mM ATP, respectively, before (black trace) and after (gray trace) addition of the L-type Ca²⁺ channel blocker nifedipine (1 µM). Both K⁺ (not shown) and ATP (Figure 7A) responses were highly reproducible (n = 4). Panels B and C show the mRNA and protein levels for the pore-forming subunit of the L-type Ca²⁺ channel (Cacna1c and Cav1.2) in control (black bars) and Dicer KO (white bars) bladder. Expression of CamKIIδ is shown in D (n = 6–10).