Effects Of CaN And NFATc On Proliferation And Migration Of Pulmonary Artery Smooth Muscle Cells From Pulmonary Hypertension Rats

Pulmonary vascular remodeling is the main pathological changes in Pulmonaryhypertension, and pulmonary vascular remodeling is due to the increasing of Ca2+incytoplasm. The recent studies show that the rise of Ca2+could activate calcineurinby calmodulin, which could regulate the different subtypes of nuclear factor ofactivated T cells, and then the NFATc participate in regulation of proliferation invascular smooth muscle cells. In this study, PH model rats were established by themeans of chronic hypoxemia (CH) and MCT injection to cultivate the pulmonaryartery smooth muscle cells (PASMCs) from the pulmonary arteries (PAs), and on thebasis of two models’ PASMCs, reveal the proliferation and migration treated withcyclosporin A (CosA) and tacrolimus (FK506), both of them are specific immuneinhibitors. And then find the theoretical background for the pharmacotherapy of PH.Objective: To investigate the effects of CosA and FK506on proliferation andmigration of pulmonary artery smooth muscle cells from CH-induced and MCT- treated pulmonary hypertension rats in vitro, and find the theoretical background forthe pharmacotherapy of PH.Methods: The PH model was induced in SD male rats exposed with CH (10%oxygen) for21days, and another model is to give MCT (50mg/kg) to SD rats bysingle intraperitoneal injection as MCT-group, and then separate the pulmonaryarteries from the two models, at the same time CH-grpup was cultivated thepulmonary artery smooth muscle cells (PASMCs) in modular incubator chamber(3%oxygen) and MCT-group was in constant temperature incubator(37℃). Theobservation items: right ventricular mass index (RVMI), mean right ventricularsystolic pressure(mRVSP), mean right ventricular pressure(mRVP), histologicalstaining and morphometry; cyclosporin A was used in the PASMCs’ cultivation toexamine the situation of proliferation by MTT and CCK8and the changes ofmigration by scratch method. Tacrolimus was used in the PASMCs’ cultivation toexamine the situation of proliferation by MTT and CCK8and the changes ofmigration by scratch method.Results:①In comparison to the CON: RVMI, mRVP and mRVSP was improvedobviously in CH-induced and MCT-treared PH, in CH and MCT rats the thickness ofpulmonary arteriolar smooth muscles was increased, pulmonary vasculars wereremodeled.②Without any drugs treated, the proliferation of the two models wasincreased and the CH group depended on the cell culture time, the difference betweenCH/MCT and CON are obvious. The result suggested that PH could improve theproliferation.③CosA was used on CH/MCT group, the proliferation was suppressed,and there is no difference between CH/MCT group and CON group on the degree ofinhibition.④FK506was used on CH/MCT group, the proliferation was suppressed,and there is no difference between CH/MCT group and CON group on the degree ofinhibition. The results suggested that CosA and FK506inhibited the signal molecules CaN and then depressed the proliferation.⑤Without any drugs, compared with CONthe migration was increased in CH and MCT.⑥FK506depressed the PASMCs’migration, but there is no difference between CH/MCT and CON. The resultssuggested that CosA and FK506inhibited the signal molecules CaN and downregulate the migration from CH and MCT-induced PH.Conclusion: Pulmonary hypertension can regulate Ca2+signaling pathway to makethe proliferation and migration of PASMCs increase significantly. Through the roleof the specific inhibitors CosA and FK506of CaN in two different models, bothproliferation and migration of PASMCs were inhibited. This suggested thatCaN/NFATc signaling pathways involved in regulating cell proliferation andmigration. But the differences between Chronic hypoxia and MCT are not obviously.