Salbutamol

Salbutamol, also known as albuterol and sold under the brand name Ventolin, is a medication that opens up the medium and large airways in the lungs. It is a short-acting β2 adrenergic receptor agonist which works by causing relaxation of airway smooth muscle. It is used to treat asthma, including asthma attacks, exercise-induced bronchoconstriction, and chronic obstructive pulmonary disease (COPD). See also [1].

The is found in smooth muscles throughout the body, especially in the lungs. It normally binds adrenaline, resulting in dialation of the bronchioles, which leads to increased oxygen intake. Salbutamol is an agonist, meaning it binds in the same place as adrenaline and stimulates the same response.

The β2 adrenergic receptor has seven (shown in grey; hydrophilic residues are shown in pink) alpha helices that cross the cell membrane. When shown in a , where the N terminus is shown in blue, the C terminus in red, and the intervening segments following the colors of the rainbow, the seven long helices that form a diagonal bundle, with shorter helices forming "caps" on either end can be seen more clearly.

The shows many intermolecular interactions between the protein and the drug. The phenyl ring of the salbutamol is sandwiched by , while the N and O in salbutamol form with nearby asparagine (Asn) and aspartate (Asp) residues.

Adrenergic agonists share structural characteristics, including ~, approximately 0.5 nm from the in the para position on the phenyl ring, and o.65 nm from the in the para position on the phenyl ring. The OH group and the phenyl ring are in the same plane, while the four atom angle between the O and the N is approximately 70 degrees.