Figure 4. Chymotrypsin-like preoteasome activity in iHTM cells after exposure to tBHP with or without pretreatment with SB203580. The luminescence intensity of the control cells was 26869±1156.353. After tBHP exposure for 1 h, the luminescence intensities of the SB203580(−) and SB203580(+) cells were 7901.95±236.98 and 10493.25 ±146.49; and those of the SB203580(−) and SB203580(+) cells were 6734.9±273.23 and 9943 ±111.23 (A). After tBHP exposure for 1h, the chymotrypsin-like proteasome inactivations in SB203580(-) cells and SB203580(+) cells were 70.59±0.88 and 60.94±0.55. After tBHP exposure for 2 h, those in SB203580(-) cells and SB203580(+) cells were 74.93±0.54 and 62.99±0.41 respectively (B). The data were presented as mean±SD, n=4, p<0.05.