REDUCTION OF PLASMA-RENIN SUBSTRATE AFTER PARTURITION - ROLE OF RENIN

  • 1 January 1982
    • journal article
    • research article
    • Vol. 42  (4) , 391-394
Abstract
Plasma renin substrate concentration, renin activity, serum sex hormone binding globulin and total protein concentration were measured sequentially in 10 women after elective cesarean section. Plasma renin substrate concentration decreased from 5406 .+-. 999 .mu.g AI [angiotensin I]/l (mean .+-. SD) at term to 2369 .+-. 726 .mu.g AI/l 6 days post partum. Plasma renin activity decreased from 6.2 .+-. 3.3 .mu.g AI/l per h at term to 4.2 .+-. 4.0 .mu.g AI/l per h 6 days after delivery. Serum sex hormone binding globulin decreased more slowly than plasma renin substrate concentration. Clearance of plasma renin substrate based on plasma renin activity was calculated. This consumption by renin could explain only 12% of the decrement in plasma renin substrate concentration at the steepest part of the plasma renin substrate disappearance curve. Metabolic clearance of plasma renin substrate may be much greater than that calculated from plasma renin activity.