Chronotropic

Now, norepinephrine does have some beta-1 effects.

Remember we said beta-1 receptors are on the heart, and that can mildly increase contractility and mildly increase heart rate, cause the heart to squeeze harder and cause it to beat faster, right? Chronotropic support, right? And inotropic support.

So chronotropic support is heart rate.

Inotropic support is contractility.

Heart rate increases are known as chronotropy.

So inotropy is contractility.

Chronotropy is heart rate.

So beta-1 receptor agonism stimulating beta-1 receptors in the heart, dobutamine increases myocardial contractility, also known as inotropy, and it increases heart rate, also known as chronotropy, although the primary effect is this increase on myocardial contractility.

Dobiumine does have some slight beta-2 adrenergic effects.