Table 4.

Effect of granzyme-treatment on the activity of caspases in TIIcells from normoxic and hyperoxic rats

	Control		Hyperoxia
Granzyme	-	+	-	+
Caspase 8	100	155 ± 7*	100	110 ± 4*
Caspase 3	100	216 ± 14*	100	155 ± 10*

Caspase activity in freshly prepared TIIcells of rats exposed to air (control) or oxygen for 48 hrs (hyperoxia) was determined colorimetrically as described in Materials and Methods. In some experiments, cell lysates were incubated in the presence of granzyme prior to determination of caspase activity (see Methods). Values are means ± s. d. given in arbitrary units (values without granzyme = 100) of n = 3 independent experiments. Asterisk indicates a significant difference between granzyme-treated and untreated samples (p < 0.05).