RAPID INCREASE IN PLASMA AND URINARY CYCLIC GMP AFTER BOLUS INJECTION OF ATRIAL NATRIURETIC FACTOR IN MAN

Abstract

We studied the effects of a bolus injection of 50/Ug synthetic human atrial natriuretic factor (ANF) on the cyclic GMP and cyclic AMP levels in plasma and urine of eight normal men. Administration of the hormone increased basal immunoreactive (IR-)ANF levels in plasma 2.8-fold to 110 pM three minutes after injection. Thereafter, IR-ANF levels rapidly declined to basal levels. Plasma cyclic GMP levels increased 2.6-fold to 16.6 nM within 6 minutes after ANF and decreased to near basal values within 30 minutes. Urinary cyclic GMP excretion increased 2.8-fold, whereas urinary volume and sodium excretion increased less than two-fold in the 30 minutes after ANF. Plasma cyclic AMP levels did not change. The data indicate that changes in plasma IR-ANF levels are followed by changes inplasma cyclic GMP and in urinary cyclic GMP excretion and suggest that cyclic GMP is a biological marker for circulating ANF in man.