Figure 4.

Chemokine gene expression in the rat brain in response to Lipopolysaccharides (LPS), with and without morphine tolerance. Gene expression of the chemokines C-C motif chemokine ligand (Ccl)2, Ccl5, Ccl7, Ccl11, Ccl12, C-X-C motif chemokine ligand (Cxcl)1, and Cxcl3 in the brains of rats with and without morphine tolerance, following an i.p. injection of either 250 µg/kg LPS or saline (n = 3–5 rats per group), was determined using a Polymerase Chain Reaction (PCR) array. Data were calculated using the ΔΔCT method relative to the control group (placebo-control + saline) and are represented as a fold change. * p < 0.05, ** p < 0.01, *** p < 0.001