PHOSPHATE ESTERS IN MYOTONIC HUMAN MUSCLE

Abstract

Four 100 mg. muscle samples were obtained by biopsy from a patient with myotonia congenita. The usual ester fractions and some unidentified fractions were found. The quantitative findings showed that symptoms of myotonia resembled those of fatigued normal muscle. After "working off" the myotonia, the monophosphate esters resembled those of normal resting muscle and unidentified esters appeared. On both nervous and mechanical stimulation intense electrical activity occurs in myotonic muscle, resembling tetanic contraction of normal muscle. Myotonia is interpreted to be entirely a result of the hyperexcitability of the muscle membrane.