What response is primarily triggered by Beta II receptors?

Beta II receptors are primarily found in various tissues, including smooth muscle, particularly in the airways, blood vessels, and gastrointestinal tract. The stimulation of these receptors leads predominately to smooth muscle relaxation. This effect is particularly significant in the bronchioles where beta II receptor activation results in bronchodilation, making it easier for air to flow into the lungs. Additionally, relaxation of vascular smooth muscle can lead to vasodilation in certain vascular beds, contributing to the regulation of blood flow.

The design of beta II receptors in the body’s response system highlights their role in facilitating processes that require increased airflow and decreased resistance, aligning with a need for improved oxygen delivery and efficiency during physical activity or stress.