Erythrocyte spectrofluorometric abnormalities in myotonic dystrophy during "in vitro" aging

The possibility in Myotonic dystrophy (MyD) that a decreased ATP utilization by the membrane may produce modifications in glycoprotein structure and/or in the supramolecular arrangement of some membrane proteins was investigated in human erythrocytes: a) by determining the membrane sialic acid content and the cellular ATP concentration in eight cases of MyD; b) by evaluating the stability of the membrane glycoprotein structure by in vitro ageing experiments; c) by testing the presence of high molecular weight aggregates of proteins on the membrane; d) by evaluating the physico-chemical properties of the membrane by 1-anilino 8-naftalensulfonate as a fluorescent probe. Our evidence suggests that ATP concentration and membrane sialic acid content are within normal values. Only in two cases did a decreased stability of membrane glycoproteins occur while the supramolecular assembly of membrane proteins could be considered as normal. The fluorescent probe behavior after in vitro aging was indicative of a decreased polarity of its micro-environment.