P-selectin In Angiotensin â…¡-induced Vascular Remodeling Caused By Hypertension And Its Mechanism

Aim:To study of p-selectin on angiotensin Ⅱ-induced vascular remodeling caused by hypertension model in mice and its possible mechanism.Methods:(1)ModelC57BL/6strains of P-selectin gene knockout mice, using micro-pump infusion of angiotensin II construct hypertension model.(2)GroupingWere randomly assigned to4groups:WT+PBS(negative control),P-selectin-/-+PBS(blank control),WT+AngⅡ(positive control),P-selectin-/-+AngⅡ (experimental group).(3Experimental methodsELISA Kit assay in mice plasma to detect content of TNF-a, TGF-betal;HE staining to determine groups of thoracic aorta media thickness (MT), luminal internal (LD) and MT/LD;Masson staining observation of vascular collagen content;Real-time fluorescent quantitative PCR for detection of vascular expression of TGF-betal and Smad3, Smad7gene; Immunohistochemical staining of TGF-betal, Smad2/3, Smad7to detect levels of expression of these protein in vascular.Results:(1) Compared with WT+PBS group. WT+Ang Ⅱ group in plasma of mice significantly higher content of TNF-a. TGF-beta1(TNF-a rise98%.P<0.001:TGF-beta1rise221%.P<0.001):compared with the P-selectin-/-+Ang II group, WT+Ang11mice elevated plasma content of TNF-a, TGF-beta1is obvious,(TNF-a rise92%,P<0.001;TGF-beta1increase212%,P<0.001); compared with the P-selectin-/-+PBS group, P-selectin-/-+Ang II group mice with elevated plasma content of TNF-a, TGF-beta1(TNF-a rise35%,P<0.01;TGF-betal rise28%,P<0.05), but not as good as the first two raised significantly.(2) Compared with WT+PBS group, WT+AngⅡmice aorta MT, marked increases in the value of the MT/LD (MT values rise56%,P<0.001;MT/LD rise50%,P<0.001); and P-selectin-/-+Ang II comparison of group WT+Ang II mice aorta MT, also registered marked increases in the value of the MT/LD (MT values rise69%,P<0.001;MT/LD rise59%,P<0.001).(3) Compared with WT+PBS group, WT+AngⅡgroup collagen contents in mice aorta up98%(PO.001), compared with the P-selectin-/-+AngⅡgroup, WT+AngⅡ group collagen contents in mice aorta up94%(P<0.001).(4) Compared with WT+PBS group, WT+Ang II group in mice aorta TGF-betal, expression of Smad3gene significantly increases (TGF-betal expression rise of97%,P<0.001;Smad3rise79%,P<0.001); compared with the P-selectin-/-+AngⅡ group, WT+AngⅡ group in mice aorta TGF-betal, expression of Smad3gene sharp,(TGF-betal expression-expression of114%,P<0.001;Smad3rise93%,P<0.001); compared with the P-selectin-/-+PBS group, WT+PBS group mice aorta TGF-betal, expression of Smad3gene rise (TGF-betal expression-expression of19%,P<0.01;Smad325%,P<0.01), but not as good as the first two raised significantly and WT+PBS group compared WT+AngⅡexpression of Smad7gene reduce the level of98%(P<0.05), compared with the P-selectin-/-+Ang groupⅡ, WT+AngⅡ expression of Smad7gene reduce the level of78%(P<0.05); compared with the P-selectin-/-+PBS group. P-selectin-/-Ang groupⅡexpression of Smad7gene reduce the level of45%(P<0.05). Conclusion:(1) P-selectin promote expression of inflammatory factor TNG-α and TGF-β1in plasma,Ang Ⅱ plays a coordination role.(2) AngⅡtriggered the morphological changes of vascular remodeling induced by P-selectin.(3) P-selectin to raise the expression of TGF-beta1,Smad3protein and mRNA, main through strengthene the positive feedback of TGF-beta1/Smads signal pathway promoting vascular VR, AngⅡplay collaborative role.(4) AngⅡcan ruduce Smad7protien expression and mRNA level by inhibiting the negative feedback of TGF-beta1/Smads signal pathway promoting vascular VR.