Catechol-O-methyltransferase activity in erythrocytes of pregnant women

Catechol-O-methyltransferase (COMT) is the enzyme that converts catechols, e.g., catecholamines and catechol estrogens, to their methyl ethers. COMT activity measured in erythrocytes (RBC's) of healthy men (No. = 47) and healthy nonpregnant women (No. = 53) was 8.2 +4- 0.17 nmoles X ml.-1 (mean and standard error). The COMT activity in RBC's of healthy pregnant women (No. = 100) was 10.7 +/- 0.29 nmoles X ml.-1 RBC X hr.-1, a value which is significantly higher than that found in RBC's of men and nonpregnant women (p less than 0.001).