MACROMOLECULAR FORMS OF ATRIAL NATRIURETIC POLYPEPTIDES - GLOBULIN BINDING IN HUMAN PLASMA

Macromolecular forms of atrial natriuretic polypeptides in human plasm a were analyzed by chromatographic separation and immunoblotting. Anal yses were done with the plasma fraction obtained from Affi-Gel Blue wi th low-molarity buffer, known to elute mostly globulins. Immunoblottin g with anti-hANP revealed five major immunoreactive bands with molecul ar weights between 205 and 27.5 kDa. Only two specifically detected pr otein bands (approximate to 80 and approximate to 36 kDa) were identif ied by comparison with control immunoblots incubated with anti-hIgG. T he presence of IgG in plasma and chromatographic extracts is a problem in the study of ANP-binding proteins.