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ARMIN WOLF ANAL REAL ACAD. FARM.

significant differences compared with the respective CsA group without inhibitor are
indicated by #P0.05, ##P0.01 and ###P0.001.

The specific inhibitors of caspase-1, caspase-3 and caspase-6 were
co-incubated at concentrations of 100 µM with 0 and 50 µM CsA for 4
hours and with 0, 10 and 25 µM CsA for 20 hours. After 4 hours, Ac-
DEVD-CHO (Nicholson et al. 1995) statistically significantly inhibited
CsA-induced chromatin condensation and fragmentation to between 50
and 60 % of their initial values (Fig. 9). After 20 hours of incubation
chromatin condensation was reduced by the caspase-3 inhibitor by 83 %
(10 µM CsA) and 65 % (25 µM CsA). Ac-DEVD-CHO reduced DNA
fragmentation by 65 % (10 µM CsA) and 83 % (25 µM CsA). While the
caspase-6 inhibitor had only a slight inhibitory effects, on both chromatin
condensation and on chromatin fragmentation after 4 hours of incubation,
statistically significant 28 % inhibitory effect was found on chromatin
fragmentation after 20 hours after coincubation with 50 µM CsA. No
effect on chromatin condensation and fragmentation was observed with
caspase-1 inhibition.

After 20 hours of incubation, CsA-induced LDH release (50 µM)
was reduced by the caspase-3 inhibitor, Ac-DEVD-CHO, to nearly 45 %
of leakage values obtained with CsA without the inhibitor. No significant

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