[Effect of static work on the baroreceptor reflex in cats]

10 cats were trained to pull a weight for escaping a noxious stimulation. Arterial pressure and heart rate increased during isometric exercise, while cardiac output did not change. Artificial rising of the blood pressure by noradrenaline infusion or by short-lasting occlusion of thoracic aorta was used to test chronotropic component of the baroreceptor reflex. The baroflex bradycardia was partly inhibited during presentation of conditioned stimulus (tone 1000 Hz) and even more during isometric exercise. Mechanisms of the suppression of baroflex during muscular exercise are discussed.