ULTRASTRUCTURE OF THE ZINC IODIDE-OSMIC ACID STAINED CELLS IN GUINEA-PIG SMALL-INTESTINE

This study has demonstrated that cells stained using the zinc iodide-o smic acid (ZIG) method have the same fine structural features as those of fibroblasts. They have a well developed Golgi apparatus, granular endoplasmic reticulum and many mitochondria. They have no basal lamina . They are distributed in association with the deep muscular plexus, w ithin the outer circular muscle layer and in the space between the cir cular and longitudinal muscle layers. Since this staining method is be lieved to co-stain nerves and interstitial cells of Cajal, we conclude d that these ZIG-positive, fibroblast-like cells represent at least so me, if not all, of the interstitial cells which appeared in the origin al description by Cajal.