Some Histochemical Observations on Periodic Acid-Amino-Acid Mechanisms

Abstract

THE periodic acid Schiff technique has been used histochemically primarily as a means of localizing the 1,2 glycol linkage in tissue sections¹. It is known, however, that periodic acid is also capable of cleaving the 1,2 hydroxylamino linkage with the production of some aldehyde radicals, and although the exact reaction mechanism is not understood, it is believed by some to react in a somewhat similar manner with a number of amino-acids possessing structurally neither of these linkages. The amino-acids serine and threonine, as well as the “hydroxylysine” of Van Slyke, fall into the first category, whereas cystine, methionine, tryptophane, glycine, alanine, tyrosine, histadine, aspartic and glutamic acids fall into the latter group². This investigation was initiated to study specifically this phase of the periodic acid Schiff mechanism, and although the results were not conclusive, it was felt that a brief description of the experiments might be of interest to others working in this particular field.