Intrinsic Factor, Nonintrinsic Factor Vitamin B12 Binder, and Pepsinogen Secretion in Normal Subjects: Quantification using intragastric neutralization and inorganic phosphate as a marker

Abstract

A technique of quantifying gastric secretion in normal subjects while maintaining the gastric contents at neutral pH is described. Phosphate buffer was used to achieve continuous intragastric neutralization during stimulated gastric secretion using maximal doses of histalog. Inorganic phosphate in the buffer served as a gastric marker, and the evidence to support its use is reported in detail. The method was applied to the quantification of intrinsic factor, nonspecific B12 binder, and pepsinogen secretion in 6 normal subjects. Differing patterns of secretion of these three constituents of gastric juice were observed. The output of intrinsic factor was not sustained and appeared to represent a true washout phenomenon. The secretion of nonspecific B12 binder was not influenced by histalog stimulation. The pattern of pepsinogen secretion clearly differed from that of intrinsic factor and appeared to be one of true stimulation. It is suggested that this technique may have a wider application, particularly in the quantification of other gastric juice macromolecules which are susceptible to intragastric proteolysis and/or acid degradation.