Extract from the above information

1. It has a positive inotropic effect on the myocardium, mainly acting on β1 receptors, and has relatively little effect on β2 and α receptors. 2. It can directly excite cardiac β1 receptors to enhance myocardial contraction and increase stroke volume, thereby increasing cardiac output. 3. It can reduce peripheral vascular resistance (reduced afterload), but systolic blood pressure and pulse pressure generally remain unchanged, or only increase due to increased cardiac output. 4. It can reduce ventricular filling pressure and promote atrioventricular node conduction. 5. Myocardial contractility is enhanced, and coronary blood flow and myocardial oxygen consumption often increase. 6. Due to increased cardiac output, renal blood flow and urine volume often increase.

Not clearly described