1β immunoreactivity in the walls of the middle cerebral artery
and microvessels following subarachnoid hemorrhage
(SAH). Images represent (A) sham, SAH + vehicle and SAH + U0126, 2 days after SAH; (B) sham, SAH + vehicle and SAH + U0126, 3 days after SAH; and (C) sham and SAH, 4 days after SAH. There was a significant increase in IL-1β protein which was located in the SMCs and endothelium (arrowhead) in the MCA and in the surrounding microvessels (white arrows) after SAH + vehicle as compared to sham-operated rats at 2 and 3 days with maximum at 3 days. IL-1β immunoreactivity was slightly increased at 4 days in the MCA in SAH group as compared with the sham group. Treatment with U0126, given at 6 h after induced SAH, prevented the increased protein expression at 2 and 3 days. (D) Bar graph showing semiquantification of fluorescence intensity for IL-1β in MCA. Data are presented as the mean percentage relative to sham ± SEM; n = 5. *P <0.05, **P <0.01.