Comparison of biochemical and physiological characteristics among white, pink, and red muscle fibers in carp (cultured)

Abstract

As part of a program to clarify the influence of difference of muscle fiber types in ordinary muscle on rigor mortis progress of fish, this study compared and examined the biochemical and physiological characteristics of muscle fiber types in relation to the muscular contraction and relaxation among white (W), pink (P), and red (R) muscle fibers of carp (cultured). The contents of ATP-related compounds and glycogen just after killing, lactate dehydrogenase activity, and myofibrillar Mg²⁺-ATPase activity in ordinary muscle were higher in the order of W>P>R, R≅P>>W, W≅P>>R, and P≥W>>R, respectively. From these results, it was suggested that the capacity of anaerobic energy supply for rigor mortis progress might be higher in the order of pink muscle fiber, white muscle fiber, and red muscle fiber. The maximum level reached by caffeine contraction was considerably higher in pink muscle fiber than in white muscle fiber, in the order of P>>W>R. However, sarcoplasmic reticulum (SR) Ca²⁺-ATPase activity, SR Ca²⁺ uptake rate, and SR Ca²⁺ release rate were not higher in pink muscle fiber than in white muscle fiber, in the order of P≅W>>R, W>P>R, and W>P>R, respectively. The surface area and volume percentages of SR against sarcomere were higher in the order of P>W>R and P>>W>R, respectively, and well supported the result of caffeine contraction. The superprecipitation reaction of actomyosin was higher in the order of P≥R>>W. This result suggested that the characteristic of actomyosin in relation to muscular contraction may be markedly different among white, pink, and red muscle fibers.