Determination of calcium ions effluxed from smooth muscle into Ca2+-free physiological solution by means of Ca2+-selective electrode.

In order to measure Ca2+ efflux from the smooth muscle into a Ca2+-free physiological solution, the method using a Radiometer Ca2+-sensitive electrode was applied and compared with the method using an atomic absorption spectrophotometer to examine its usefulness. The results obtained show that the Ca2+ electrode used here can accurately and continuously monitor free calcium ions effluxed from the smooth muscle into a Ca2+-free solution. The Ca2+-sensitive electrode used here is a useful tool to investigate Ca2+ efflux from the smooth muscle into a Ca2+-free physiological solution.