Patent ID: 7907999

Claim:
An apparatus for measuring physiological characteristics of an intact trachea in vitro, comprising: a perfusion device configured to flow a perfusion liquid through the trachea; a differential pressure device operable to measure a pressure difference of the perfusion liquid flowing through the trachea; a set of current electrodes comprising at least a first current electrode and a second current electrode operable to pass an applied current through the epithelium of the trachea between the first and second current electrodes; and a set of voltage-sensing electrodes comprising at least a first voltage-sensing electrode and a second voltage-sensing electrode operable to detect a transepithelial potential difference between the voltage-sensing electrodes; a vessel containing an extraluminal bath and adapted to receive the trachea in the bath; wherein the first voltage electrode is in electrical continuity with the perfusion liquid flowing and the second voltage electrode is disposed in the extraluminal bath; and wherein the first current electrode is in electrical continuity with the perfusion liquid and the second current electrode is disposed in the extraluminal bath wherein the second current electrode completely surrounds the perfusion device and the second voltage electrode.