Long-term potentiation at marrow level induced through EMG-biofeedback

Abstract

Introduction. The long-term potentiation (LTP) of synaptic transmission constitutes a remarkable example of synaptic plasticity, and represents a learning model. The LTP has been described by several authors in the hippocampus through high frequency stimulation. Objectives, patients and methods. In the present paper we have used conventional EMG-biofeedback techniques which aims at investigating the rehabilitation of myopathies and the electrophysiological mechanism of neuromuscular learning at marrow level. Three experimental patients of progressive muscular dystrophy, aged between I I and 15, were systematically treated with EMG-biofeedback in several muscular groups. Special attention is given to the records corresponding to rest post-maximum effort (RPME). Results. For the principal muscular groups rehabilitated it has been verified that the motor unit potentials corresponding to RPME show intense activity, with average amplitudes of 600-700 muV and duration close to 15 ms, against a practically nonexistent activity before rehabilitation. The descent of the alkaline phosphatase (from 200 U/l to 50 U/l) and the lactic-deshydrogenase Conclusions. The EMG-biofeedback techniques allow its to (from 320 U/l to 210 U/l) are specially significant physical efficiency inpatients of progressive muscular dystrophy. The analysis of post-biofeedback motor unit potentials, and the strong descent of the enzymes in the last phase of treatment, allows us to deduce the establishment of LTP between the alpha-motoneurons and the axonic terminals of the microneurons of Renshaw. The mechanism of the LTP at marrow level is interpreted through two physiological hypotheses concerning the circuit of Renshaw.