ß-agonists

ß-agonists

Endogenous norepinephrine can stimulate α1, α2, β1 and β2 receptors. Most drugs are created to be either agonists or antagonists that are more selective for one or two receptors. However, no substance so far has shown 100% selectivity. β-agonist agents are more selective for the β-receptors.

 

β1-receptors are abundant in the circulation and skeletal muscle, β2 in smooth muscle (particularly in the respiratory tree).

Commonly used drugs of this group are ephedrine, salbutamol, salmeterol, formoterol, and terbutaline.

1

The β-receptors in airways are β2 type.

2

Many tissues contain β-receptors. 

3

To induce bronchodilation, a patient with asthma is treated with a combination of salbutamol (beta-2 agonist) and ipratropium (antagonist of the muscarinic acetylcholine receptor.) Indicate for salbutamol what type of ligand it is for the autonomic nervous system.

4

To induce bronchodilation, a patient with asthma is treated with a combination of salbutamol (beta-2 agonist) and ipratropium (antagonist of the muscarinic acetylcholine receptor.) Indicate for ipratopium what type of ligand it is for the autonomic nervous system.