Any decrease in the availability of iron for incorporation into the heme moieties of hemoglobin results in an increase in the erythrocyte protoporphyrin concentration. Our aim was to compare protoporphyrin concentrations, determined spectrophotometrically, with body iron stores, as assessed from the amount of iron demonstrable by Prussian blue staining of bone marrow aspirates. The mean protopo...

1. The activity of erythrocyte 6aminolaevulinic acid (ALA) dehydratase and blood protoporphyrin concentrations have been measured in patients with various anaemias, a group of subjects with known lead exposure and a group of control subjects. Leucocyte ALA synthase was measured in subjects from the last two groups. 2. Erythrocyte ALA dehydratase activity was significantly depressed in the group...

The intraerythrocytic Plasmodium falciparum parasite converts most of host hemoglobin heme into a nontoxic heme crystal. Erythrocyte zinc protoporphyrin IX, normally present at 0.5 microM, which is a ratio of 1:40,000 hemes, can elevate 10-fold in some of the anemias associated with malaria disease protection. This work examines a binding mechanism for zinc protoporphyrin IX inhibition of heme ...

A patient with greatly increased erythrocyte protoporphyrin, but normal porphyrins in urine and feces, is described. The patient later developed a malignant lymphoma, and the reason why she accumulated protoporphyrin in her erythrocytes is not known. The protoporphyrin in the erythrocytes consisted of two types of protoporphyrin, free protoporphyrin (30%) and zinc protoporphyrin (70%). Upon irr...

We describe a fluorometric method for determining zinc protoporphyrin, in which whole-blood specimens collected in heparin/ethylenediaminetetraacetate are prediluted with water, and zinc protoporphyrin is extracted into ethanol/ water (95/5 by voi). The resulting extract has a low absorbance (0.05) at the excitation wavelength (415 nm) of zinc protoporphyrin, and the extraction efficiency is ab...

The dimorphic blood picture in sideroblastic anemia suggests the coexistence of at least two types of erythrocyte, the populations with the smaller RBCs being responsible for the crucial abnormality, namely the impairment of iron incorporation into protoporphyrin. In a patient with sideroblastic anemia who subsequently developed acute myelocytic leukemia, we found a light and a heavy cell popul...

Lead intoxication was first associated with increased coproporphyrin excretion almost 100 years ago; but not until the 1930's were abnormalities in blood protoporphyrin detected. These later findings have been interpreted as an inhibition by lead of iron incorporation into protoporphyrin during heme synthesis. The testing and application of this hypothesis had to await three more decades of res...

Increased free erythrocyte protoporphyrin concentrations and depressed motor nerve conduction velocities (MNCV) were observed in 45 patients on maintenance haemodialysis. Neither of these findings could be correlated with age, duration or frequency of dialysis, or the degree of uraemia present. A strong negative correlation (r=--0-53; P less than 0-001), however, existed between the free erythr...

Each of 65 laboratories analyzed 10 whole-blood samples for erythrocyte protoporphyrin by one or more of several analytical procedures. These procedures were of two types: (a) extraction of protoporphyrin from the erythrocytes into ethyl acetate/acetic acid, re-extraction into hydrochloric acid, and fluorometric measurement; or (b) direct reading in a portable fluorometer (hematofluorometer), w...