Читать книгу Fundamentals of Pharmacology for Paramedics - Группа авторов - Страница 28

An opioid drug such as morphine acts by binding to the receptors for endogenous opioids and, by activation of those receptors, produces similar actions to those generated by the endogenous opioids, including analgesia and a range of other effects. Similarly, bronchodilator drugs such as terbutaline and salbutamol, used during an episode of acute asthma, produce their bronchodilator effect by activating adrenergic beta receptors on the airways. These receptors would be activated physiologically by adrenaline and noradrenaline secreted during the fight or flight response, and the binding of adrenaline or noradrenaline to the beta receptors in the airways would produce a dilation of the airways, allowing a more rapid ventilation of the lungs. A drug which is able to produce this effect without producing the rest of the fight or flight response is a very useful therapeutic agent during an episode of acute asthma (Figure 1.1).