Coronary blood flow of unanaesthetized dogs with experimental coronary artery disease

Experimental coronary artery disease (CAD) was produced in dogs which had chronically implanted catheters for the measurement of mean arterial pressure (MAP) and coronary blood flow (CBF) using the 85Kr clearance technique. Resting CBF was determined in the conscious animal during intracoronary infusion of saline and the 'maximum' CBF was determined by infusion of ATP (0s·6 and 0·8 mg/min). Repeated observations revealed only small and variable changes in MAP and CBF of control dogs over a two-month period and of dogs fed an atherogenic diet containing thiouracil and cholesterol for 47 and 54 days. CAD was produced by intracoronary infusion of allylamine and intravenous infusion of egg yolk emulsion. This treatment results in arteritis, lipid deposition, and fibrosis. The disease was associated with a 37% decrease in maximum CBF within two to five days. Resting CBF decreased 16% and MAP was not altered significantly. After the initial decrease in maximum CBF, there is a stable period with decreased maximum CBF for at least six weeks.