Muscles proximal to the fracture plane atrophy after limb autotomy in decapod crustaceans

Abstract

AbstractIn crabs (Carcinus and Uca) and crayfish (Procambarus), autotomy of distal limb segments is followed by atrophy of all leg muscles proximal to the fracture plane. The extent of the reversible muscle degeneration was revealed in light micrographs and was quantified by extracting the muscles and weighing them. In the period between autotomy and the next molt, the muscles which move the limb stump shrink to approximately 50% of the weight of contralateral muscles proximal to an intact leg. The atrophied muscles appear wasted in situ and in cross section, but are still innervated and continue to be activated.