Diuretic and haemodynamic effects of MK 447 in normotensive and hypertensive sheep

The short term effects of the novel diuretic MK 447 were examined in both normotensive and hypertensive (ACTH treated) conscious sheep. The drug had profound diuretic, natriuretic and kaliuretic effects in both groups. Plasma sodium was unchanged but plasma potassium fell and haematocrit increased. Plasma renin concentration increased with MK 447 in the normotensive but not the hypertensive sheep. In the normotensive sheep cardiac output fell, peripheral resistance increased and blood pressure was unchanged. In the hypertensive ACTH treated sheep cardiac output and blood pressure fell but resistance was unchanged.