Agar gel electrophoresis of proteolytic enzymes in gastric juice of patients with chronic gastritis.

Abstract

Agar gel electrophoresis with proteolytic digestion of albumin substrate and subsequent Chromoscan analysis of the agar slide, were used to study the proteolytic enzymes of gastric juice in 28 patients with atrophic gastritis with or without intestinal metaplasia, 7 patients with chronic superficial gastritis and 6 with a normal gastric mucosa. Five proteolytic enzyme spots, designated I through V in order of decreasing anodic mobility, were found in gastric juice from normal controls. Of these spots, Spot II (pepsin) was largest; Spot III (presumably gastricsin) was next in prominence, followed by Spot I (prepepsin, presumably degradation product or products of pepsin). Spot IV, of slow anodic mobility (pepsinogen), was rather small and sometimes absent, and Spot V was seen only rarely and in traces. In 12 of 14 cases of atrophic gastritis without intestinal metaplasia, Spots II and III were diminished in area and well demarcated. Spot IV was often large and Spot I was most often absent. Twelve cases of atrophic gastritis with intestinal metaplasia and 2 cases of gastric atrophy showed either: a) absence of all five spots (5 cases, including 3 of pernicious anemia) or b) a marked reduction of area and good demarcation of Spots II and III with absence or reduction of Spot I (8 cases); in 1 case, Spots I, II, and III were absent. In 4 cases of atrophic gastritis with or without intestinal metaplasia (of which 3 were associated with gastric cancer) a distinct Spot V was seen. In 6 of the 7 cases of chronic superficial gastritis, a normal pattern was seen; in 1 case the pattern resembled that seen in atrophic gastritis without metaplasia. We believe this method of analyzing proteolytic enzymes in gastric juice is of interest for evaluating chronic gastritis.