Gastric clearance of serum albumin in normal man and in certain gastroduodenal disorders.

Serum albumin gastric loss was estimated from the measurement of non-dialysable radioactivity of the gastric juice after intravenous injection of radioiodinated serum albumin (RISA). Immunochemical quantitation of serum albumin was performed in some of the samples. In the control group, the mean gastric clearance of albumin was 1.71 ml per hour with a range of 0.41 to 4.41 ml per hour. This represented a gastric loss of 1.9 gram of albumin per day and 11% of the daily degradation of albumin. There was no significant change in the gastric albumin loss after stimulating the gastric secretion. No significant difference in the gastric albumin leakage was found between normal subjects and patients with gastric or duodenal ulcer. IN PERNICIOUS ANAEMIA ALBUMIN LOSS INTO THE STOMACH WAS GREATER (MEAN: 3.72 ml per hour; SD 1.52 ml) than in the normal group and accounted for the greater albumin fractional catabolic rate. This fact had never been proved before. In both patients with giant rugae of the gastric mucosa the gastric clearance of serum albumin was also increased. It is concluded first that albumin is not secreted by the chief and parietal cells of the mucosa and probably passes through the gastric wall between the cells of the mucosa, perhaps during the exfoliation of the surface epithelial cells, and secondly that the stomach is one of the sites of serum albumin breakdown, a fact that supports the view that the gastrointestinal tract plays a major role in the catabolism of serum albumin.