Inhibition of the positive atrial chronotropic effect of isoproterenol by exposure to an acrylate floor finish.

Application of a commercial acrylate sealer/finish to the floor of our animal quarters resulted in almost complete elimination of the positive chronotropic response of the hypoxic rat atria to isoproterenol. Forty-eight hours exposure to this sealer/finish decreased sensitivity to isoproterenol by approximately 1000-fold and decreased maximal response by 70%. The elimination of the response to isoproterenol was associated with the resin portion of the sealer/finish and was reversible on removal of the rats from exposure to the product.