Figure 6. Mechanical stretch of tissue using the double-barreled electrode + force apparatus.

Tissue was mechanically stretched 1 mm using a micrometer drive over 2–3 seconds. The stretch did not induce a contraction (A) and did not result in localized bioelectrical activity (C). A large negative deflection of the K-sensitive electrode (B) was observed for 3–4 seconds after beginning the stretch, but recovery to 0 mV was rapid and no positive voltages associated with stretch were observed. After 45 seconds, a spontaneous contraction occurred, and positive responses were observed from both the K-sensitive, and the bioelectrical sensing halves of the double-barreled electrode. Data obtained under flow conditions, T = 37°C.