part_of part of smooth muscle cell tracheobronchial smooth muscle cell 2020-07-21T12:50:22Z Tracheobronchial smooth muscle cells are universally located in the tracheobronchial tree and play a critical role in controlling and modulating the size of the airway lumen, thereby contributing significantly to the airflow resistance. These cells display both phasic and tonic characteristics, which are vital for airway contractility. Phasic activity manifests as cyclic contraction and relaxation, similar to the behavior seen in gastrointestinal smooth muscle cells, whilst tonic activity resembles vascular smooth muscle cells, maintaining a constant degree of tension. These features enable tracheobronchial smooth muscle cells to constrict the airways in response to various mechanical and chemical stimuli, including allergens, parasympathetic nervous stimulation, changes in gas composition, and cold air, thus protecting the delicate alveoli from potential damage. Tracheobronchial smooth muscle cells, beyond their contractile function, actively contribute to airway remodeling in conditions like asthma. Their proliferative and synthetic capabilities lead to smooth muscle hypertrophy, hyperplasia, and the production of extracellular matrix components, collectively causing abnormal airway narrowing. (This extended description was generated by ChatGPT and reviewed by the CellGuide team, who added references, and by the CL editors, who approved it for inclusion in CL. It may contain information that applies only to some subtypes and species, and so should not be considered definitional.) A smooth muscle cell that is part of the tracheobronchial tree. smooth muscle cell of tracheobronchial tree The marker set ACTA2, TAGLN can identify the Human cell type tracheobronchial smooth muscle cell in the lung with a confidence of 0.69 (NS-Forest FBeta value). tracheobronchial tree