Fig. 2.

Representative traces of conductance and current-voltage (I-V) plots of oocytes expressing CFTR and β₂-adrenergic receptor (βAR). A: conductance of an oocyte perfused with FR, then activated with isoproterenol and IBMX (I+I), followed by a 5-min exposure to cigarette smoke extract (CSE) containing I+I, and lastly a washout with I+I. B: I-V plot at peak activation with I+I, 5-min exposure to CSE, and washout with I+I. C: conductance of an oocyte perfused with FR, then activated with I+I, followed by a 10-min exposure to CSE containing I+I, and lastly a washout with I+I. D: I-V plot at peak activation with I+I, 10-min exposure to CSE and washout with I+I.