Which hormones increase heart rate?

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Hormones regulate heart rate through direct effects on the heart’s pacemaker and through overall metabolic control. Epinephrine and norepinephrine rapidly raise heart rate by binding beta-1 adrenergic receptors in the SA node, which raises cAMP, speeds the depolarization rate, and enhances conduction and contractility. Thyroid hormone (T3) increases heart rate more gradually by boosting the expression of beta-1 receptors and other proteins involved in cardiac excitation, making the heart more responsive to catecholamines and intrinsic pacemaker activity. Acetylcholine tends to slow the heart by acting on muscarinic receptors, so it decreases rate rather than increases it. Dopamine’s effect on heart rate is variable and not a primary driver in the same way as the other hormones. So, epinephrine, norepinephrine, and T3 together account for the conditions that raise heart rate.