The Early Protective Effect Of Sufentanil Preconditioning On Vascular Endothelial Cells Of Abdominal Aorta In Rats

Objective (1) To investigate whether ischemic preconditioning and sufentanil preconditioning with various doses could induce the early protective effect on vascular endothelial cells after abdominal aorta ischemic-reperfusion in rats; (2) To investigate the roles of opioid receptor, nitric oxide and nitric oxide synthase in the early protective effect of vascular endothelial cells which is induced by sufentanil preconditioning; (3) To detect the expression of endothelial nitric oxide synthase and inducible nitric oxide synthase in the early protective phase by the methods of immunohistochemistry and reverse transcription Polymerase Chain Reaction, then identify their contribution in this effect.Methods The experiment consisted of three parts: (1) Sprague-Dawley rats were divided into six groups, including group NA, group I/R, group IPC, group SUL1, group SUL2 and group SUL3, group NA was given nothing just segregated the abdominal aorta and the inferior vena cava, group I/R was given ischemia of thirty minutes and reperfusion of one hundred and twenty minutes, group IPC was added ischemia of five minutes and reperfusion of five minutes three times, group SUL1, group SUL2 and group SUL3 were given sufentanil fiveμg/kg, tenμg/kg and twentyμg/kg separatedly before ischemic-reperfusion, plasmic soluble Thrombomodulin and von Willebrand Factor were determined, Circular Endothelial Cells were calculated, and the injury of vessel was examined with optical and electron microscope, then investigated whether ischemic preconditioning and sufentanil preconditioning with various doses could induce the early protective effect on vascular endothelial cells; (2) opioid receptor antagnist naloxone, nitric oxide precursor L-Arginine and nitric oxide synthase antagnist N₆₀-Nitro-Arginine Methyl Ester were used both respectively (group NLX, group L-Arg and group L-NAME) and combinedly with sufentanil tenμg/kg (group N-SUL, group LA-SUL and group LN-SUL) for preconditioning before ischemic-reperfusion, and group NA, group I/R, group IPC and group SUL (tenμg/kg) were also done simultaneously, we determined plasmic soluble Thrombomodulin, plasmic von Willebrand Factor and Circular Endothelial Cells calculation to evaluate the injury of vascular endothelial cells, plasmic nitric oxide, nitric oxide of aorta homogenate and nitric oxide synthase activity of aorta homogenate were also determined, then investigated the roles of opioid receptor, nitric oxide and nitric oxide synthase in the early protective effect of vascular endothelial cells which is induced by sufentanil preconditioning; (3) We detected the expression of endothelial nitric oxide synthase and inducible nitric oxide synthase in the early protective phase by the methods of immunohistochemistry and reverse transcription Polymerase Chain Reaction of four groups (group NA, group I/R, group IPC and group SUL), then identify their contribution in this effect.Results (1) The abdominal aorta ischemic-reperfusion model was succeeded, compared with group NA, mean arterial pressure of the other five groups was rising during block phase associated with lower heart rate, then became opposite during reperfusion phase, mean arterial pressure and heart rate became normal in one hour after reperfusion, the fluctuation of group I/R was more severe than group IPC, group SUL1, group SUL2 and group SUL3, the concentration of plasmic soluble Thrombomodulin, plasmic von Willebrand Factor and Circular Endothelial Cells calculation of group I/R was also higher than group IPC, group SUL1, group SUL2 and group SUL3, and the images of vessel examined by optical and electron microscope also showed less injury in group IPC, group SUL1, group SUL2 and group SUL3, the concentration of plasmic soluble Thrombomodulin, plasmic von Willebrand Factor, Circular Endothelial Cells calculation and images of optical and electron microscope of group SUL2 were better than group SUL1 and group SUL3; (2) the concentration of plasmic soluble Thrombomodulin, plasmic von Willebrand Factor, Circular Endothelial Cells calculation, plasmic nitric oxide, nitric oxide of aorta homogenate and nitric oxide synthase activity of aorta homogenate in group NLX were not different to those indices in group I/R, indices of group N-SUL were better than those of group I/R, but worse than those of group IPC and group SUL, indices of group L-Arg were not different to those of group IPC and group SUL, indices of group LA-SUL were better than those of group IPC and group SUL, indices of group L-NAME and group LN-SUL were the worst. (3) The positive result of immunohistochemistry was brown color in cytoplasm, the positive cells of endothelial nitric oxide synthase in group IPC and group SUL were more than those cells in group NA and group I/R, the positive cells of inducible nitric oxide synthase in group I/R were more than other groups, the results of reverse transcription Polymerase Chain Reaction showed that expression of endothelial nitric oxide synthase in group IPC and group SUL were better than group NA and group I/R, expression of inducible nitric oxide synthase in each group were lower and had no differences.Conclusion (1) ischemic preconditioning and sufentanil preconditioning with various doses could induce the early protective effect on vascular endothelial cells after abdominal aorta ischemic-reperfusion in rats, tenμg/kg of sufentanil is the most effective dose relatively; (2) Naloxone could partly block the protective effect while N₆₀-Nitro-Arginine Methyl Ester could totally block the effect, it is indicated that opioid receptor maybe partly mediates the early protective effect of vascular endothelial cells which is induced by sufentanil preconditioning, while nitric oxide and nitric oxide synthase could be the major effective factors in the early protective phase; (3) the expression of endothelial nitric oxide synthase is increased during the early protective effect of ischemic preconditioning and sufentanil preconditioning, inducible nitric oxide synthase doesn't play a part in the early effect.