SIMULTANEOUS RECOGNITION OF IONOCYTES AND MUCOUS CELLS IN THE GILL EPITHELIUM OF TURBOT AND IN THE RAT STOMACH

A simple and rapid method is described which allows the recognition of different types of epithelial cells in one paraffin section. In the f ish gill, the ''chloride cells'' (also called ionocytes or mitochondri a-rich cells) appeared black and well contrasted after the zinc iodide -osmium (ZIO) fixation, a contrast which is preserved after staining w ith alcian blue. All mucous cells appeared pale beige and can be clear ly distinguished from the other cells but the known specificity of alc ian blue for acid and sulfate mucins was lost. A complex tissue like t he gill showed an interesting metachromasia. The combined ZIO fixation and alcian blue staining has also been applied on another epithelium, the rat stomach. (C) 1996 Wiley-Liss, Inc.