论文部分内容阅读
Objective: To investigate the effect of Iptakalim(Ipt) preventing injury of endothelial microvesicles(EMVs) derived from hypoxia/reoxygenation(H/R)-treated HUVECs on the relaxation of rat thoracic aortic rings and explore the underlying mechanism. Methods: H/R injury model was established to release H/R-EMVs from HUVECs. H/R-EMVs from HUVECs were isolated by ultracentrifugation from the conditioned culture medium. H/R-EMVs were characterized by using Transmission Electron Microscope(TEM). Thoracic aortic rings of rats were incubated with 10~(-7)-10~(-3 )mol/L Ipt and co-cultured with 10 μg/ml H/R-EMVs for 4 hours, and their endothelium- dependent relaxation in response to acetylcholine(ACh) was recorded in vitro. The nitric oxide(NO) production of ACh-treated rat thoracic aortic rings was measured by using Griess reagent. The expression of endothelial NO synthase(e NOS), phosphorylated e NOS(p-e NOS, Ser-1177), serine/threonine kinas(Akt) and phosphorylated Akt(p-Akt, Ser-473) in the thoracic aortic rings of rats was detected by Western blotting. Results: H/R-EMVs were induced by H/R-treated HUVECs and isolated by ultracentrifugation. The isolated H/R-EMVs subjected to TEM revealed small, rounded vesicles(100–1 000 nm) surrounded by a membrane. H/R-EMVs impaired relaxation induced by ACh of rat thoracic aortic rings significantly. Compared with H/R-EMVs treatment individually, relaxation and NO production of rat thoracic aortic rings were increased by Ipt treatment in a concentration-dependent manner(P<0.05, P<0.01). The expression of total e NOS(t-e NOS) and total Akt(t-Akt) was not affected by Ipt or H/R-EMVs. However, the expression of p-e NOS and p-Akt increased after treated with Ipt(P<0.01). Conclusion: Based on H/R-EMVs treatment, ACh induced endothelium-dependent relaxation of rat thoracic aortic rings was ameliorated by Ipt in a concentration-dependent manner. The mechanisms involved the increase in NO production, p-e NOS and p-Akt expression.
Objective: To investigate the effect of Iptakalim (Ipt) preventing injury of endothelial microvesicles (EMVs) derived from hypoxia / reoxygenation (H / R) -treated HUVECs on the relaxation of rat thoracic aortic rings and explore the underlying mechanism. Methods: H / H / R-EMVs from HUVECs were isolated by ultracentrifugation from the conditioned culture medium. H / R-EMVs were characterized by using Transmission Electron Microscope (TEM). Thoracic aortic rings of rats were incubated with 10 -7 -10 -3 mol / L Ipt and co-cultured with 10 μg / ml H / R-EMVs for 4 hours, and their endothelium-dependent relaxation in response to The nitric oxide (NO) production of ACh-treated rat thoracic aortic rings was measured by using Griess reagent. The expression of endothelial NO synthase (e NOS), phosphorylated e NOS (pe NOS, Ser -1177), serine / threonine kinas (Akt) and phosphorylated Akt (p-Akt, Ser-473) in the The isolated H / R-EMVs subjected to TEM revealed small, rounded vesicles (100- 1 000 nm) surrounded by a membrane. H / R-EMVs impaired relaxation induced by ACh of rat thoracic aortic rings significantly. Compared with H / R-EMVs treatment individually, relaxation and NO production of rat thoracic aortic rings were increased by Ipt treatment The expression of total eNOS (teNOS) and total Akt (t-Akt) was not affected by Ipt or H / R-EMVs. However, the expression of pe NOS and p-Akt increased after treated with Ipt (P <0.01). Conclusion: Based on H / R-EMVs treatment, ACh induced endothelium-dependent relaxation of rat thoracic aortic rings was ameliorated by Ipt in a concentration-dependent manner . The mechanisms involved the increase in NO production, pe NOS and p-Akt expression.