Denervation exposes cryptic concanavalin A binding sites in skeletal muscle membranes

Denervation produces significant changes in glycoproteins on the surfaces of skeletal muscles which can be detected as an increase in membrane-bound carbohydrate and an increase in specific binding of labelled lectins. The increased binding of concanavalin A to denervated membranes is detectable only in intact membranes and is abolished by treatments which disrupt or perturb membrane structure whereas the increased binding of Ricinus communis agglutinin is detectable under both conditions. We suggest that, in addition to chemical modification of existing carbohydrate chains in glycoproteins and the synthesis of new glycoproteins, denervation results in an altered geometric arrangement of existing membrane glycoproteins.