Fig. 5

Sufentanil, but not fentanyl or remifentanil, attenuates ATP/ADO release from U937 monocytes, affecting U937-HUVECs adhesion. a Fentanyl, sufentanil, and remifentanil have no cytotoxic effects on U937 monocytes (n = 4). Cell vitality is detected using cell counting kit-8 kit assays. The data of absorbance are normalized to control. b Fentanyl, sufentanil, and remifentanil have no effects on Cx43 expression in U937 monocytes (n = 4). Cx43 expression is detected by western blotting. The gray values of blots are normalized to control. c Sufentanil, but not fentanyl or remifentanil, attenuates ATP release from U937 monocytes (n = 4, *P < 0.05 vs control). ATP release is detected with ATP bioluminescence assay kits. The intensity of bioluminescence is normalized to control. d Sufentanil, but not fentanyl or remifentanil, attenuates the ADO content from U937 monocytes (n = 4, *P < 0.05 vs control). The ADO content is detected using related ELISA kits. The data of absorbance are normalized to control. e Application of exogenous ATP and ADO reduces U937-HUVEC adhesion, when U937 monocytes are pre-treated with fentanyl; APCP reverses the decrease in U937-HUVEC adhesion provoked by exogenous ATP (#P < 0.05 vs fentanyl group; △P < 0.05 vs fentanyl+ATP group); f Application of exogenous ATP and ADO reduces U937-HUVEC adhesion, when U937 monocytes are pre-treated with sufentanil; APCP reverses the decrease in U937-HUVEC adhesion provoked by exogenous ATP (n = 5, *P < 0.05 vs control; #P < 0.05 vs fentanyl group; △P < 0.05 vs sufentanil+ATP group); g Exogenous ATP and ADO reduce U937-HUVEC adhesion, when U937 monocytes are pre-treated with remifentanil; APCP reverses the decrease in U937-HUVEC adhesion provoked by exogenous ATP (#P < 0.05 vs fentanyl group; △P < 0.05 vs remifentanil +ATP group). U937-HUVECs adhesion is detected by adhesion assays. The data of adhesion fraction are normalized to control. Fentanyl (Fen): 10 μg/ml, for 24 h; sufentanil (Suf): 25 ng/ml, for 24 h; remifentanil (Remi): 50 ng/ml, for 24 h; APCP: 300 μM, for 1 h; exogenous ATP: 200 μM, for 1 h; exogenous ADO: 100 μM, for 1 h. ADO, adenosine; APCP, α, β-methylene ADP; HUVEC, human umbilical vein endothelial cell. All experiments are conducted in the presence of TNF-α. All data are presented as mean ± S.D.. Multiple comparisons among groups are performed using repeated-measures one-way analyses of variance, followed by Tukey post hoc comparisons