EXPERIMENTAL THYROTOXIC MYOPATHY - AUTORADIOGRAPHY OF PROTEIN-SYNTHESIS IN SKELETAL-MUSCLE AND MOTOR-NEURONS OF SPINAL-CORD

The total protein synthesis was studied in skeletal muscle and spinal motor neurons in experimental thyrotoxic myopathy (TM) mice by using r adioautography with H-3-methionine. A significant increase of mean spe cific radioactivity was found in motor neurons of mice with TM. No sta tistical differences were established in the level of H-3-methionine i nclusions into muscle fibre proteins of experimental and control anima ls. Thus, the total protein synthesis in motor neurons is significantl y increased with TM, while there is no change in the skeletal muscle. Our data suggest that muscular weakness in TM is not the consequence o f protein metabolism disorders in skeletal muscle fibres.