Lung cells make and secrete ceramide in response to cigarette smoke extract. A: Ceramide levels in A549 cells treated with PBS- or 10% cigarette smoke extract-containing medium without (CSE) or CSE with myriocin (CSE + Myr), a ceramide inhibitor, for 12 h (n = 6). B: Ceramides in culture medium of A549 cells following a 12-h treatment with PBS or CSE (n = 6). C. Ceramides were determined from whole blood of adult mice following 5 d of room air (CON) or sidestream cigarette smoke (CS) (P =0.069; n = 5). *P <0.05 for CSE vs. PBS.