SUPERIMPOSED IMAGERY FOR INTRACELLULAR FREE CALCIUM-ION DISTRIBUTION AND CELLULAR STRUCTURE WITH VIDEO FLUORESCENCE MICROSCOPY

In life science research, the distribution of intracellular free calcium ion concentration ([Ca2+]i) is widely done using a fluorescent indicator dye such as Fura-2, Indo-1. Of particular interest is correspondence between [Ca2+]i distribution and cellular structure. This report describes a system for superimposition of [Ca2+]i distribution and cellular microscopic images made with transmitted light or Nomarski differential interference. This system uses the instrumentation described in the previous report but with improved the computer software. The superimposed image shows 24 colors for [Ca2+]i and 7 levels of black-and-white in the microscopic image. [Ca2+]i images of NG108-15 corresponded well with transmitted light image of microscope. However, the [Ca2+]i and differential interference image differed by parallel shift, rotation and magnification cause by insert of the Nomarski prism, etc. in imcroscopic light path. The superimposed image was particularly affected by parallel shift. The parallel translation of microscopic images was included in the image processing program in the order to bring the image into correspondence.