FIGURE 2.

Time course of morphine-induced changes in TSP1 gene expression in MOR1-transfected immortalized astrocytes. A, cells were treated with either a single dose of morphine (1 μm) for 5, 27, and 48 h in the absence of serum or with morphine (1 μm) in media and serum daily for 8 days. Fresh media with serum but devoid of morphine were added for the last 24 h to the cells in the 8-day experiment. *, p < 0.05 versus control (Con), n = 4. B, cells were treated with a single dose of morphine (1 μm) for 5, 27, and 48 h and maintained in the presence of serum along with fresh morphine for the last 3 h. TSP1 gene expression was measured by qRT-PCR as described under “Experimental Procedures” normalizing with GAPDH for relative quantification. **, p < 0.01; ***, p < 0.001, versus control; †, p < 0.05 versus serum in the absence of morphine; n = 4–5. M, morphine; S, serum.