Role of M3 receptor in penehyclidine hydrochloride-induced reduction of increased permeability of human pulmonary microvascular endothelial cells caused by endotoxin: the relationship with MAPK signaling pathway / 中华麻醉学杂志

ABSTRACT

Objective To evaluate the role of M3 receptor in penehyclidine hydrochloride(PHC)-induced reduction of increased permeability of human pulmonary microvascular endothelial cells (PMVECs) caused by endotoxin and the relationship with mitogen-activated protein kinase (MAPK) signaling pathway.Methods Human PMVECs were seeded in 6-well plates (2 ml/hole) or in culture flasks (4 ml/flask) at the density of 1 × 105 cells/ml and randomly divided into 6 groups (n=5 each):control group (group C),M3 receptor shRNA transfection group (group shRNA),lipopolysaccharide (LPS) group,penehyclidine plus LPS group (group P+LPS),LPS plus M3 receptor shRNA transfection group (group LPS+shRNA) and PHC plus LPS plus M3 shRNA transfection group (group P+LPS+shRNA).The cells were transfected with shRNA plasmid containing 2.5 nmol/L M3 receptors in shRNA,LPS+shRNA and P+LPS+shRNA groups.LPS at the final concentration of 0.1 μg/ml was added at 24 h of incubation and then cells were incubated for 1 h in LPS and LPS+shRNA groups.PHC at the final concentration of 2 μg/ml was added at 24 h of incubation,cells were incubated for 1 h,then LPS at the final concentration of 0.1 μg/ml was added,and cells were incubated for another l h in P+LPS and P+LPS+shRNA groups.The permeability of PMVECs was measured using Transwell assay.The expression of phosphorylated p38 MAPK (p-p38 MAPK)and phosphorylated extracellular signal-regulated protein kinase 1/2 (p-ERK1/2) was detected by Western blot,the expression of heat shock protein 27 (HSP27) using immunofluorescent staining,and the expression of M3receptor mRNA by real-time polymerase chain reaction.Results Compared with group C,M3 receptor mRNA expression was significantly down-regulated in group shRNA,and the permeability of cells was significantly increased,and the expression of p-p38 MAPK,p-ERK1/2,HSP27 and M3 receptor mRNA was up-regulated in group LPS (P＜0.05).The permeability of cells was significantly decreased,and the expression of p-p38 MAPK,p-ERK1/2,HSP27 and M3 receptor mRNA was down-regulated in P+ LPS,LPS+shRNA and P+LPS+shRNA groups as compared with group LPS,and in group P+LPS+shRNA as compared with group LPS+shRNA (P＜0.05).Conclusion The mechanism by which PHC reduces endotoxin-caused increased permeability of human PMVECs is related to inhibiting activation of MAPK signaling pathway after down-regulating M3 receptor.