Pulmonary stretch receptors are mechanoreceptors found in the lungs

Human lung

The human lungs are the organs of respiration in humans. Humans have two lungs, with the left being divided into two lobes and the right into three lobes. Together, the lungs contain approximately of airways and 300 to 500 million alveoli, having a total surface area of about in...

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When the lung expands, the receptors imitate the Hering-Breuer reflex

Hering-Breuer reflex

The Hering–Breuer inflation reflex, named for Josef Breuer and Ewald Hering, is a reflex triggered to prevent over-inflation of the lungs. Pulmonary stretch receptors present in the smooth muscle of the airways respond to excessive stretching of the lung during large inspirations.Once activated,...

, which reduces the respiratory rate

Respiratory rate

Respiratory rate is also known by respiration rate, pulmonary ventilation rate, ventilation rate, or breathing frequency is the number of breaths taken within a set amount of time, typically 60 seconds....

. Increased firing from the stretch receptors also increases production of pulmonary surfactant

Pulmonary surfactant

Pulmonary surfactant is a surface-active lipoprotein complex formed by type II alveolar cells. The proteins and lipids that surfactant comprises have both a hydrophilic region and a hydrophobic region...

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Intercostal muscles and diaphragm receive impulses from the respiratory centre, stretch receptors in the lungs send impulses to the respiratory centre giving information about the state of the lungs.