Fig. 4. Changes in transepithelial voltage (V_te) and short circuit current (I_sc) in response to a hypotonic stress (decrease of Ringer osmolarity from 315 mOsm to 175 mOsm). - sign of V_te refers to the mucosa (grounded); - sign of I_sc indicates current flowing from mucosal to serosal side. V_te time course represents the registered trace, while I_sc time course was performed by keeping the preparation `short circuited' every 5 min. Representative time course of N=20 trials.