Ethanol Inhibition of Haemoglobin Synthesis: In Vitro Evidence for a Haem Correctable Defect in Normal Subjects and in Alcoholics

S ummary . The effect of ethanol in different concentrations ranging from 0.10 to 0.66 m on globin chain synthesis in vitro was studied by measuring 3 H‐leucine incorporation into human bone marrow suspensions and reticulocyte‐enriched blood. With increasing concentration of ethanol there was a decreasing 3 H‐leucine incorporation. This inhibition was reversed by haem and pyridoxine hydrochloride (PHC) in i mM concentration. 5‐Aminolaevulinic acid (5‐ALA) at similar concentration had no significant effect. The addition of haem to reticulocyte‐enriched blood obtained from acute alcoholics increased globin‐chain synthesis by 20% whereas PHC and ALA were without effect and none of the additions increased globin synthesis by normal reticulocytes. These data provide direct evidence for the inhibitory action of ethanol on haemoglobin synthesis and suggest that the effect is mediated through inhibition of haem synthesis at a site influenced by pyridoxine.