ALB and diabetes mellitus: This was in contrast with a predominant large molecular peak of presumably undegraded, tritiated albumin with greatly diminished quantities of small fragments in a macroalbuminuric patient with diabetes.6 The exact anatomic location of the degradation pathway has not been determined, but it probably takes place in cells distal to the glomerular basement membrane, most probably in tubular epithelial cells, where albumin is subjected to endocytosis and trafficked to lysosomes.