Figure 7.
CBV maps acquired from a DTH animal before (A) and 6 h after (B) LPS injection, demonstrating an increase in rCBV in the zone surrounding the lesion 6 h after LPS injection. Subtraction (post-Gd − pre-Gd) T1-weighted images acquired before (C) and 6 h after (D) LPS injection. Areas showing no BBB breakdown appear black, and areas in which there is breakdown of the BBB and leakage of the contrast agent into the tissue appear white. Breakdown of the BBB is evident throughout the lesioned (left) hemisphere 24 h after LPS injection in this animal. E, Graph showing the increase in the L/R ratio for the area of increased CBV (from thresholded images) 6 h after LPS injection in DTH animals (black bars; n = 11). This increase was significant compared with pre-LPS values in this group (§p < 0.05). No significant change in rCBV was seen in control DTH animals over time (white bars; n = 5). F, Graph showing temporal changes in the area of contrast enhancement, which reflects BBB breakdown, in DTH animals (black bars; n = 11) after LPS injection compared with untreated DTH animals (white bars; n = 5). Data are given as mean ± SEM; baseline data were obtained 1 d before LPS injection (day 42), and time points in brackets represent post-LPS injection.