Mean critical values at different velocities.

<p>Mean (± S.E.M.) of the P₁ values at five different velocities in a fiber activated with pCa²⁺ 4.5 (dotted line), 6.0 (solid line) and treaded with blebbistatin (solid line with inverted triangles). Blebbistatin changed P₁ significantly at all five velocities. *Significantly different from all other conditions (P<0.05).