FIGURE 8.

Fluorescent ionophore imaging of TCMK1 and C2C12 cells during pFUS. Representative Fluo-4 images of (A) TCMK1 and (E) C2C12 cells before and during pFUS. (B, F) Quantification of fluorescence intensities reveal that pFUS significantly increases Fluo-4 intensities in both cell types and Fluo-4 transients are effectively blocked loading with BAPTA-AM or incubating cells with 2 μM verapamil. (C, G) Partial replacement of Na⁺ in the extracellular solution with Cs⁺ also blocked Fluo-4 Ca²⁺ transients in both cell types, demonstrating dependence of Ca²⁺ transients on transmembrane Na⁺ potential. (H) Na⁺-dependent Fluo-4 Ca2⁺ transients were not affected by incubating C2C12 cells with 1 μM tetrodotoxin (TTX). (D, I) TRPC1 suppression by shRNA knockdown in each cell type resulted in diminished Fluo-4 Ca²⁺ transients compared to cells transfected with scramble control shRNA sequences. (J, L) Representative CoroNa transients during pFUS of TCMK1 and C2C12 cells. TRPC1 suppression in (K) TCMK1 cells or (L) C2C12 cells led to diminished CoroNa Green Na⁺ transients compared to cells transfected with scramble control shRNA sequences. (* = p<0.05 by t-test for pairwise comparisons or ANOVA for multiple comparisons).