The effect of methylprednisolone on intracellular calcium of normal and dystrophic human skeletal muscle cells

Clinical trials have shown that a glucocorticoid, the methyiprednisolone (P DN), has: a beneficial effect on muscle strength and function in Duchenne m uscular dystrophy (DMD) patients. The aim of this study was to test if the effect of PDN could be mediated via a possible action on intracellular calc ium. The intracellular calcium activity, at rest and during calcium mobiliz ing drug superfusion protocols was recorded in normal and dystrophic human cocultured muscle cells. PDN (10 mu M) pretreatment induced an elevation of the resting calcium concentration of 51, 34 and 38% in proliferating norma l myoblasts, DMD myoblasts and DMD myotubes, respectively, while normal myo tubes resting [Ca2+](i) was not altered. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.