Fig. 10

Quantification of β-arrestin pathway proteins in CD11b+ cells from center of lesion 24-h after morphine administration. Total Protein Stain as internal loading control for normalization of target signals (A). Protein collected from rats treated for 3 days with i.v. drug administration. Loading control: protein extracted from whole spinal cord tissue from sham rats treated with saline (lanes 2–3). Western blot image (B) protein was collected from rats that received 3 days of consecutive i.v. drug treatment and samples taken 24-h after the last drug dose and processed with LI-COR system. B Western blot images were cropped to remove irrelevant sections of the image and display only the proteins of interest. The contusion injury significantly increased the expression of β-arrestin (C) and p38 MAPK (D) on day 3. Additionally, morphine significantly decreases the expression of p38 MAPK by day 7 compared to saline-treated rats (D).  There was a trend towards higher expression of ERK 1 (E) and ERK 2 (F) with on day 3 of morphine treatment but no significant effects were found. Results shown as Mean ± S.E.M. *p < 0.05, n = 6