Interrelationship between acetylcholine and prostaglandins in the control of sodium excretion and renin secretion in anesthetized dogs. I

Abstract

The interrelationships between acetylcholine (ACH) and prostaglandins in the control of sodium excretion (UNaV) and of renin secretion (RS) were examined in unilaterally-nephrectomized, anesthetized dogs with or without treatment with indomethacin, an inhibitor of prostaglandin synthetase. Inrarenal infusion of ACH (40 microgram/min) in control animals produced diuresis and natriuresis. UNaV was 9.2 +/- 3.1 muEq/min during control periods and was 74.7 +/- 31.6 muEq/min after 40 min of infusion of ACH (p less than 0.05). UNaV was still 48.0 +/- 16.8 muEq/min after 100 min of infusion of ACH (p less than 0.05). RS rate was 930.6 +/- 188.5 U/min during control periods, and was 737.4 +/- 220.3 U/min after 100 min of infusion of ACH (p greater than 0.1). In the dogs treated with indomethacin, the natriuresis produced by ACH could not be sustained. UNaV was 46.6 +/- 12.1 muEq/min before and was 34.7 +/- 12.8 muEq/min 100 min following the infusion of ACH (p greater than 0.1). Arterial plasma renin activity was 3.29 +/- 0.83 ng/ml/h before and was 20.97 +/- 7.78 ng/ml/h after 100 min of infusion of ACH (p less than 0.025). The data suggest that prostaglandins are involved in the sodium excretion and the renin secretion produced by acetylcholine.