Device to Measure Muscle Contractile-Relaxant and Epithelial Bioelectric Responses of Perfused, Intact Tracheal Airways Tissue In Vitro

CDC and collaborative researchers have developed a device allowing for simultaneous measurement of smooth muscle contractile/relaxant activity and transepithelial potential difference (Vt) [or short circuit currents (Isc)] and resistance (Rt) within an intact airway in vitro. Investigation of the underlying mechanisms of lung diseases, such as asthma or cystic fibrosis, involves understanding the roles of airway smooth muscle and epithelium. Smooth muscle is involved in the control of the airway diameter; epithelium regulates the ionic composition of the liquid lining the airways through electrogenic ion transport and releases factors that regulate the ability of smooth muscle to contract.

This invention allows for the measurement and study of pulmonary diseases under conditions retaining normal spatial relationships between all the cell types and an unmanipulated/undistorted tracheal airway wall. Further, the device permits evaluation of epithelial functional integrity using pharmacological techniques. Agents can be separately added to the lumen, where they must first cross the epithelium to reach the smooth muscle, or to the outside of the airway, where there is no hindrance of said agents to the muscle. The invention also permits the effective in vitro screening of the effects of agents and drugs on airway epithelium and smooth muscle within the same preparation.