Accession Number : AD0623377

Title :   AN ELECTROPHYSIOLOGICAL INVESTIGATION OF NEUROMUSCULAR TRANSMISSION IN MYASTHENIA GRAVIS,

Corporate Author : LUND UNIV (SWEDEN) DEPT OF PHARMACOLOGY

Personal Author(s) : Elmqvist,D. ; Hofmann,W. W. ; Kugelberg,J. ; Quastel,D. M. J.

Report Date : 22 APR 1964

Pagination or Media Count : 20

Abstract : By the use of intracellular electrodes the neuromuscular transmission mechanism was studied in isolated intercostal muscle obtained from patients with myasthenia gravis. With repetitive nerve stimulation at frequencies above 2/sec, only the first few stimuli elicited muscle contractions in most fibers and then subthreshold endplate potentials, (epps) could be recorded. Miniature endplate potentials (mepps) had a mean amplitude 1/5 of the normal. The calculated size of the quantal components of epps corresponded closely to the mepp amplitude. Other observations made appeared normal, i.e., resting frequency of mepps, quantum content of epps, post-synaptic chemosensitivity with ACh analogs, input resistance, and resting membrane potential. It is tentatively concluded that in myasthenia gravis there is a deficiency in the amount of ACh in the quanta of transmitter released from the motor nerve terminals. (Author)

Descriptors :   (*NEUROMUSCULAR TRANSMISSION, DISEASES), (*ACETYLCHOLINE, NEUROMUSCULAR TRANSMISSION), SKELETAL MUSCLE RELAXANTS, MUSCLES, NERVES, STIMULATION(PHYSIOLOGY), CONTRACTION, SWEDEN

Distribution Statement : APPROVED FOR PUBLIC RELEASE