Certified Emergency Nurse (CEN) Practice Test 2025 - Free CEN Practice Questions and Study Guide

Beta two receptors play a crucial role in bronchodilation, which is the widening of the air passages in the respiratory system. These receptors, when stimulated by agonists, cause smooth muscle relaxation in the bronchi and bronchioles, leading to increased airflow and easier breathing. This physiological response is particularly important during asthma attacks or in conditions where respiratory airflow is compromised.

Beta one receptors are primarily found in the heart and are involved in increasing heart rate and myocardial contractility. Alpha receptors are mainly associated with vasoconstriction and other functions in the cardiovascular system. Gamma receptors are not relevant to this process, as they are not commonly discussed in the context of respiratory physiology or pharmacology. Therefore, the focus on beta two receptors in relation to bronchodilation directly correlates with their functional role in relaxing the bronchial smooth muscle and enhancing respiratory function.