SD rats were treated with the p38 MAPK inhibitor, SB203589 as indicated, and sacrificed on day 0 or 3 of RI. Tissue samples were collected from the non-ischemic normal zone (NZ) or the ischemic LAD/collateral-dependent zone (CZ). Elastin, laminin and type IV collagen degradation was determined by Western blot. Top: Representative Western blots detecting intact elastin (68 kDa), laminin (170–190 kDa) and type IV collagen (225–250 kDa) and degradation products of elastin (45 kDa), laminin (51 kDa) and type IV collagen (140, 95 and 75 kDa). Bottom: Cumulative data for degradation products, *p<0.05, n=5.