THE EFFECT OF SEVERAL PHARMACOLOGICAL AGENTS UPON RB⁸⁶ UPTAKE BY THE PERFUSED DOG HINDLIMB

¹ Department of Pharmacology, Warner-Lambert Research Institute, Morris Plains, New Jersey

A technique utilizing the perfused canine hindlimb for studies of vascular resistance, % Rb⁸⁶ uptake and oxygen uptake has been described.

Agents which caused directionally similar alterations in vascular resistance differ in their effect on % Rb⁸⁶ uptake. Among the vasoconstrictors, epinephrine and norepinephrine increased Rb⁸⁶ uptake whereas vasopressin decreased Rb⁸⁶ uptake. Among the vasodilators, histamine, nitroglycerin and pentaerythritol tetranitrate increased Rb⁸⁶ uptake whereas acetylcholine decreased Rb⁸⁶ uptake. Alterations in oxygen uptake always qualitatively followed the changes in % Rb⁸⁶ uptake.

Local hypoxia decreased vascular resistance and increased Rb⁸⁶ uptake. Shock produced by hemorrhage or epinephrine infusion increased vascular resistance and decreased Bb⁸⁶ uptake.

Dose-response rebated changes in both vascular resistance and % Rb⁸⁶ uptake to intraarterial injection of epinephrine and histamine were demonstrated.