Prevention of cell death by treatment with caspase inhibitors. (a) Effect of caspase inhibitors on HGA-induced apoptosis of primary cultured hepatocytes derived from Fah−/− Hpd−/− mice. Two hours after the treatment with the inhibitors, cell death was induced by 1 mM HGA. Pretreatment with caspase inhibitors, YVAD (•, n = 4) or DEVD (■, n = 4), protected Fah−/− Hpd−/− hepatocytes from HGA-induced apoptosis in a dose-dependent manner. Open symbols indicate means of survival rate for hepatocytes treated with YVAD (○, n = 3) or DEVD (□, n = 3) without HGA. (b) Effect of caspase inhibitors on AdHPD-induced apoptosis of primary cultured hepatocytes derived from Fah−/− Hpd−/− mice. Two hours after treatment with the inhibitors, cell death was induced by infection with AdHPD at moi 10. Pretreatment with caspase inhibitors YVAD (•, n = 4) or DEVD (■, n = 4), protects Fah−/− Hpd−/− hepatocytes from AdHPD-induced apoptosis in a dose-dependent manner. Open symbols indicate means of survival for hepatocytes that were treated by YVAD (○, n = 3) or DEVD (□, n = 3) without AdHPD.