We determined the dose-response relationship of systemic hemodynamics with graded intravenous infusions of sodium acetate (0.75, 1.50 and 3.00 microEq kg-1 min-1) in a group of dogs in the euvolemic state (N = 10) and in animals submitted to severe hemorrhagic shock (N = 7). Sodium acetate had a marked vasodilator effect on both groups, decreasing total peripheral resistance by 36.6% and 55.1%, respectively. Cardiac index increased simultaneously by 68.4% and 143.0%, respectively. Sodium acetate induced an approximate normalization of cardiac index and peripheral resistance at the highest infusion rate in the animals submitted to hemorrhagic shock. The normalization of cardiac output was due to a marked increase in heart rate in euvolemic dogs and to an increase in stroke volume in shocked animals. The hyperkinetic state of the circulation induced by the drug and a possible inotropic action of sodium acetate either direct or indirect could explain the different patterns of response.