Peripheral vasodilatation following 1,1,1-trichloroethane inhalation: peripheral vessels as a site of action.

The effects of 1,1,1-trichloroethane (1,1,1-TCE) inhalation on total peripheral vascular resistance and the possibility of the peripheral vessels being a site of action for 1,1,1-TCE were investigated in anesthetized dogs. In acute inhalation experiments, a decrease in total peripheral vascular resistance was observed following inhalation of 1,1,1-TCE concentrations sufficient to induce systemic hypotension. The threshold concentration of 1,1,1-TCE required to produce a decrease in perfusion pressure of the isolated hindlimb was approximately 0.4-0.5% in inspired air. A dose-response relationship between the decrease in perfusion pressure and 1,1,1-TCE concentration, which exceeded the threshold level, was observed. It is suggested that the decrease in total peripheral vascular resistance is related to systemic hypotension following 1,1,1-TCE inhalation; further, this vasodilator effect may be induced in the peripheral vessels, which is one of the sites where 1,1,1-TCE acts.