Biochemical indicators of muscle growth in the snow crab Chionoecetes opilio (O. Fabricius)

Effects of fasting and refeeding on metabolic processes in the crab Chasmagnathus granulata (Dana, 1851)

We assessed the effects of 3 weeks of fasting and 48 h of refeeding on the incorporation of [14C]-labeled substrate into glucose, glycogen, lipid, and protein in hepatopancreas, muscle, and gills from the crab Chasmagnathus granulata. Fasting did not change the rate of glycogen and lipid synthesis in the three tissues. Neither fasting nor refeeding affected hemolymph glucose levels. Refeeding induced a reduction in glycogen synthesis in gills, but did not affect glycogen synthesis in hepatopancreas and muscle. Fasting did not affect lipogenesis in hepatopancreas, but refeeding elevated [14C]-lipid twofold. Muscle lipogenesis was not affected by fasting or refeeding. Gluconeogenesis in the three tissues was not modified by fasting. Refeeding induced an increase in the glucose-synthesis capacity only in muscle. Fasting did not affect glyconeogenesis in hepatopancreas and gills, but induced a reduction in glycogen synthesis in muscle. Muscle-protein synthesis was not affected by fasting; however, refeeding induced a reduction in [14C]-protein. Our data show that C. granulata is a fasting-adapted animal which is able to maintain metabolic homeostasis, and that following refeeding there is an adjustment of anabolic-synthesis processes to recover metabolic reserves that were lost during fasting.