ENZYME HISTOCHEMICAL STUDIES OF INTESTINAL METAPLASIA IN HUMAN STOMACH, WITH SPECIAL REFERENCE TO ELECTRON HISTOCHEMISTRY

Abstract

Intestinal metaplasia of resected stomach was studied histochemically with regards to the relationship between the morphology and the function in absorptive cells. Alkaline phosphatase (ALP) and adenosine triphosphatase were used as the marker emzymes. Light microscopic histochemistry showed that intestinal metaplasia was classified into "Complete type" with ALP activity and "Incomplete type" without ALP activity, and that marked difference in ALP activity was also found in the neighboring glands of "Complete type" metaplastic mucosa. By electron histochemical investigations, ALP activity was positive in dense and tall microvilli, while it was negative in sparse and short microvilli of absorptive cells in the surface portion of the mucosa. However, enzymatic activity of microvilli was different in the neighboring absorptive cells of the same gland of "Complete type" metaplastic mucosa.
From the above results, intestinal metaplasia has various morphological types and various phenotypic expression of intestinal marker enzymes, and abnormal cellular differentiation may occur in intestinal metaplasia.