Porphyrin concentrations in various human tissues

Abstract

Abstract We measured the concentrations of total porphyrins and their metabolites (uro‐, hepta‐, hexa‐, penta‐, copro‐ and protoporphyrin) in various human tissues: liver, erythrocytes, skin, adipose tissue, and mammary gland. The porphyrin concentrations varied within minor limits, e.g., 3.1 ±2.3 nmol porphyrins/g liver and 0.50±0.10 nmol/g erythrocytes. No significant differences were detectable in other tissues in comparison with liver. In all tissues, the predominant metabolite was protoporphyrin, followed by coproporphyrin, whereas only low concentrations of higher carboxylatcd porphyrins such as uroporphyrin were detectable. It is concluded that porphyrin metabolism and its regulation is similar in all human tissues, perhaps with some small differences in the erythrocytes.