The effect of morphine on the expressions of adhesion molecules on HUVECs. (A) Graphs show the expressions of ICAM-1 on HUVECs incubated in LPS-Sup, Morphine + LPS-Sup and supernatant of Morphine + LPS. (B) Graphs show the expressions of VCAM-1 on HUVECs incubated in LPS-Sup, Morphine + LPS-Sup and supernatant of Morphine + LPS. (C) Graphs show the expressions of E-selectin on HUVECs incubated in LPS-Sup, Morphine + LPS-Sup and supernatant of Morphine + LPS. Values are Aexpressed as means ± SD. (D) Histograms show the characterization of ICAM-1, VCAM-1, and E-selectin expressions on HUVECs at 8-hr of incubation period. Control means unstained value. LPS + 0.1 µM of morphine means the value of when 0.1 µM morphine was co-treated with LPS in the LPS-Sup group. The percentage of positive cells from each group was recorded at 0, 4, 8, 12, and 24 hr of incubation period. In gray box, values are expressed as percentages of gated positive cells. *P < 0.05 versus the LPS-Sup group; †P < 0.05 versus Morphine + LPS-Sup.