Changes in tension generation and ATPase activity in skinned muscle fibres of the carp following temperature acclimation.

Common carp (Cyprinus carpio L.) were acclimated to either 7 degrees C or 23 degrees C for 1-2 months. Skinned fibre preparations were isolated from the white myotomal muscle, and ATPase activity measured during maximal isometric contractions. At 7 degrees C, fibres from the cold acclimated fish were found to generate more force than those from warm acclimated fish (123.1 and 97.2kN m-2 respectively), and more "work" (force X time integral) was obtained for each ATP hydrolysed. ATP turnover per myosin head in fibres from cold-acclimated fish was lower than in fibres from warn-acclimated fish (1.85 and 2.84 ATP S1(-1) s-1).