Ca2 levels in myotubes grown from the skeletal muscle of dystrophic (mdx) and normal mice.

Abstract

1. Myotubes were grown in culture from normal (C57BL/ScSn) and mdx mice and the cytosolic [Ca2+] was monitored through development (5‐21 days in culture) using fura‐2 loaded via ionophoresis. Simultaneous measurements of the membrane potential and cytosolic [Ca2+] were made in normal and mdx myotubes before, during and after stimulation by action potentials elicited following anode break excitation. All experiments were undertaken at 22 degrees C. All data are expressed as means +/‐ S.E.M. 2. A new method was developed which enabled accurate determination of the fluorescence characteristics of fura‐2 in murine skeletal muscle fibres. In the under in vitro conditions by 14.60 +/‐ 0.05, 9.40 +..