Distribution of Ca(2+)-modulating proteins in sarcoplasmic reticulum membranes after denervation

Abstract

The early response to the loss of motor innervation to the muscle is connected with an altered Ca(2+)-homeostasis. Our study, based on Western blotting, indicates that denervation influenced expression of some sarcoplasmic Ca(2+)-modulating proteins. Evidence has been brought for an increase of the level of calsequestrin and of the putative ryanodine receptor paralleled with a slight decrease of the total amount of Ca(2+)-pump protein. The expression of unchanged Ca(2+)-pump isoform and unaltered quantities of other non-junctional Ca(2+)-binding proteins support the hypothesis that changed cellular Ca2+ homeostasis include also an alteration of Ca(2+)-modulating systems, mainly from the junctional region of sarcoplasmic membranes.