Dielectric components of charge movements in skeletal muscle.

摘要: 1. Voltage clamp experiments measured transients from 10 mV steps applied about different membrane potentials, VT. Their analysis employed the Fourier transform relationship between dielectric spectra of permittivity as a function frequency, and step transient admittance, well established methods. 2. The capacitance -85 -50 rose monotonically was associated with simple decaying in both ‘on’ ‘off’ steps. At more depolarized potentials increased sharply charging current complex form, before falling again beyond transition potential. 3. Step-transient responses for were sampled above voltage range. Dielectric non-linear obtained by subtracting transforms at VC = test 4. imaginary coefficients represent spectrum loss against frequency. These showed two components. q beta component formed broad peak, when charge movements monotonic decays. A sharp low-frequency gamma peak became superimposed particular voltages charge-movement kinetics complex. 5. In contrast, relaxations. only one whose frequency relatively voltage-independent occurred transforms. 6. Both altering holding potential VH to adding 1 mM-tetracaine bathing solution reduced dependence on voltage. polarization currents relaxations beginning end step. 7. It is concluded that are composed least components: beta, tetracaine voltage-inactivated gamma. Any causal processes they might underlie would be expected