Fig. 1.

Ca²⁺ sensitivity of force generation by skinned ventricular fibres over a range of temperatures. pCa₅₀ is the Ca²⁺ concentration required to generate half-maximum force. When compared at the same temperature, trout ventricular fibres require 10 times less Ca²⁺ than those from the rat to generate the same amount of force. Figure adapted from Churcott et al. (1994).