The Influnce Of17-AAG To The Proliferation Of Carotid Arterial Vascular Smooth Muscle Cells After Injury By Balloons

Proliferation of vascular smooth muscle cells （VSMC） after coronary stentimplantation is the main pathological processes of In-Stent Restenosis（ISR）.Inhibition ofVSMC proliferation can effectively reduce the occurrence of ISR. Various drugs containedin current drug-eluting stents （DES）still have some shortcomings, looking for new drugscarried by drug-eluting stents can further reduce the occurrence of ISR.17-allylamino-17-emethoxy-geldanamycin（17-AAG） is a kind of heat shock protein90（Hsp90）inhibitor, currently in the clinic is mainly used for cancer treatment. However, its effect onvascular proliferation is not yet clear. In vitro experiments confirmed that it has powerfulanti-proliferative effect and suppression of Endothelial cells inflammation, promoting theEndothelial cells repair of the role.This experiment will be horizontally through the celland animal studies,confirmed the inhibitory effect of17-AAG on proliferation of VSMC.To evaluate its feasibility as a new type of stent coating drugs.ObjectiveStudies confirm that17-AAG on in vitro human umbilical vein smooth muscle cells(HUVSMC) induced by platelet-derived growth factor (PDGF), inhibition of proliferationactivities.Establishment of rat carotid artery after balloon injury model, given differentdoses of17-AAG-peritoneal injection of intervention and observation of rat carotid arteryafter balloon injury in neointima pathological changes and expression of PCNA.Study oneffects of17-AAG to the repair of rat carotid artery after balloon injury.Methods1.Take the HUVSMC induced by PDGF, divided into four groups (17-AAGrespectively0nmol/L,5nmol/L,20nmol/L,50nmol/L), and intervened with different dose17-AAG. Then adopt the pan-blue refusing dye method for cell counting, depicts growthcurve, to assess the proliferation of each group.2.30male SD rats (300-380g) wererandomly divided into three groups:angioplasty(intraperitoneal injection of saline solution0.5ml/2D) Group,17-AAG balloon injury treated with low dose (intraperitoneal injectionof5mg/kg·2D) group,17AAG balloon injury treated by high dose (intraperitoneal injectionof20mg/kg·2D) group. After balloon injury in28days, intercept the damage area of thesegment of fixed. Make the following observation:①Using computer image analysissystem for the intimal hyperplasia of each group: measurement of intima area (IA), media area (MA), calculating intima/media area ratio (I/M ratio).②.Immunohistochemical andimmunofluorescent method: observation of proliferating cell nuclear antigen (PCNA)expression to evaluate the VSMC proliferation.Results1. HUVSMC cultured in vitro induced by PDGF apparent proliferation, after theaddition of17-AAG, a difference in proliferation activity of each group. Degreeproliferation0nmol/L17-AAG group>5nmol/L17-AAG group>20nmol/L17-AAG group>50nmol/L17-AAG group.20nmol/L group compared with the control group significantstatistical differences (P<0.05). Compared to the20nmol/L group and the50nmol/L Groupalso had significant statistical differences (P<0.05).2. The mouse carotid artery balloon injury model successfully modeling, Pathologicalexamination prompted vascular intima hyperplasia of obvious.3. In rat carotid arteries after balloon injury in28days,3sets of neointima formationin experimental animals, and arterial wall thickening, accompanied by the proliferation ofsmooth muscle cells, Compared with the control group, treatment group VSMCproliferation is lighter, and high dose group with the lightest VSMC proliferation.4.HE staining measurement of intima area (IA), media area (MA), calculating intima/media area ratio (I/M ratio). Low-dose and control groups in I/M ratio with no statisticallysignificant differences (P>0.05), while high-dose and control groups had significantdifferences (P<0.05).5. Compared with the control group，In the low-dose group expression of PCNA in theintima and media slightly lower，But there is no statistically significant (P>0.05). In thehigh-dose group expression of PCNA in the intima and media significantly reduced，Therewas a significant statistical differences (P<0.05).Conclusion17-AAG on experimental animals and in vitro cell level have been provensignificant inhibition of proliferation of vascular smooth muscle cells.