Fig. 2. Isoflurane protects human atrial myocytes from stress-induced cell death via sarcolemmal adenosine triphosphate–sensitive potassium channel. Mid-aged (MA; A ) and old-aged (OA; B ) myocyte death was measured in time control (TC), after 30 min of oxidative stress with H2O2(STRESS), after 5 min of cell treatment with isoflurane and 5 min of anesthetic washout before stress (ISO + STRESS), and after repeating the ISO + STRESS protocol in the continued presence of HMR-1098, the sarcolemmal adenosine triphosphate–sensitive potassium channel blocker (+HMR). Responses to stress and protection by isoflurane were greater in MA than in OA myocytes. Values are mean ± SD. P < 0.05: * STRESS versus respective TC in MA and OA; ** ISO + STRESS versus STRESS in MA; # +HMR versus all other groups in MA; $ STRESS in OA versus MA.