The relation of angiotensin-converting enzyme to the pregnancy-induced hypertension-preeclampsia syndrome.
Angiotensin-converting enzyme, the polypeptide that converts angiotensin I to angiotensin II, was measured in the serum of 114 pregnant women who had normal blood pressure, pregnancy-induced hypertension-preeclampsia, and chronic hypertension with or without pregnancy-induced hypertension. Angiotensin-converting enzyme levels were unrelated to weeks of gestation. The angiotensin-converting enzyme levels were similar in normotensive women (21.1 +/- 6.9 units/ml), women with chronic hypertension without pregnancy-induced hypertension (23.1 +/- 2.7 units/ml), and patients with pregnancy-induced hypertension where magnesium sulfate (22.6 +/- 8.7 units/ml) had been administered prior to angiotensin-converting enzyme assay, but these values were significantly less than those in patients with pregnancy-induced hypertension with no magnesium sulfate (29.1 +/- 6.5 units/ml) therapy and in women with chronic hypertension with superimposed pregnancy-induced hypertension (30.7 +/- 4.4 units/ml) (p less than 0.005). Maternal venous and umbilical venous and arterial angiotensin-converting enzyme levels were as follows: The maternal venous level was less than the cord venous level and greater than the cord arterial value. Neither neonatal size nor twin gestation influenced the angiotensin-converting enzyme levels. Patients with diabetes mellitus had variable angiotensin-converting enzyme values regardless of the status of the blood pressure. The physiologic theories of blood pressure control in pregnant women are discussed in relation to the renin-angiotensin, bradykinin, and prostaglandin systems.
D000328:Adult; D001158:Arteries; D001724:Birth Weight; D001794:Blood Pressure; D001806:Blood Urea Nitrogen; D002908:Chronic Disease; D005260:Female; D005312:Fetal Blood / Q000201:enzymology; D006801:Humans; D006973:Hypertension / Q000188:drug therapy / Q000201:enzymology*; D007231:Infant, Newborn; D008278:Magnesium Sulfate / Q000627:therapeutic use; D007703:Peptidyl-Dipeptidase A / Q000097:blood*; D011225:Pre-Eclampsia / Q000188:drug therapy / Q000201:enzymology*; D011247:Pregnancy; D011263:Pregnancy Trimester, Third; D014527:Uric Acid / Q000097:blood; D014680:Veins
D014527:Uric Acid; D008278:Magnesium Sulfate; D007703:Peptidyl-Dipeptidase A