Abstract
A simple and convenient apparatus for physiological or pharmacological experiments on preparations of isolated heart muscle is described. Provision is made for recording independently from two preparations mounted in the same bath. Electrodes for stimulation or recording are incorporated in the clamps that hold the tissue. The construction ensures the maintenance of a high oxygen tension at the surface of the tissue without the mechanical artifacts that result from bubbling oxygen directly past it. papillary muscle; isolated organ bath; isolated atria; double muscle preparation; circulating salt solution; stimulating electrodes; concentration-effect curves; inotropic and chronotropic effects; oxygenation Submitted on November 5, 1964