How is beta-agonist used in management of asthma?

Used for thousands of years (herb Ma Huang), relief symptoms of acute airway obstruction, smooth muscle relaxation by activating PKA, delivered by inhaler/ pouder/ nebulizer, but we are concerned of receptor desensitization so we use long-acting beta agonists (LABA) for long term maintenance and control (better than doubling dose of ICS or adding theophylline or LPM for example)