Veterinary Neuropharmacology

β1- adrenergic receptor agonists

β₁ - ADRENERGIC RECEPTOR AGONIST

Dobutamine

Dobutamine is a synthetic direct acting catecholamine with relatively selective β₁ receptor agonistic action. Dobutamine resembles dopamine structurally, but does not cause release noradrenaline. Hence, dobutamine produces only β₁ agonistic activity.

• Pharmacological effects
  • Intravenous infusion of dobutamine increase cardiac contractility and cardiac output, without significant change in heart rate, peripheral resistance and blood pressure. Increased myocardial contractility may increase oxygen demand and coronary blood flow. Overall, dobutamine is a more effective positive inotropic than dopamine, but it does not dilate the renal vascular bed.
• Pharmacokinetics
  • Being catecholamine, not active when given orally and is given by IV route. As it is rapidly metabolized in the liver and other tissue. Its half life is too brief. Hence, it is given by continuous IV infusion.
• Clinical use
  • Primarily used as an inotropic agent in severe congestive heart failure.