The role of the calcium ion Ca2+ as an agent of intracellular control in a variety of physiological processes is well established. In vertebrate skeletal muscle fibers, Ca2+ is involved in muscle contraction, modulation of membrane permeability and regulation of metabolic activity. Recently it was suggested that ion fluxes through membranes regulate the… (More)
The membrane potential of isolated rat neurohypophyses and isolated neurosecretosomes (neurosecretory nerve endings) was monitored with the voltage sensitive fluorescent probe diS-C3-(5). K ions, in contrast to Na or Cl ions, give rise to large changes of the fluorescent signal. The fluorescent response is linearly related to log[K+]0 at values higher than… (More)
Current- and voltage-clamp experiments on Myxicola giant axons labelled with pyrene showed decreased Na+ and K+ conductances. The low-frequency membrane capacity and the gating charge transfer were slightly reduced. It may be inferred that pyrene is incorporated in some hydrophobic membrane domains close to the ionic channels.