中华心血管病杂志
中華心血管病雜誌
중화심혈관병잡지
Chinese Journal of Cardiology
2014年
9期
765-772
,共8页
糖尿病%心肌梗死%新生血管化,病理性%受体,促生长素
糖尿病%心肌梗死%新生血管化,病理性%受體,促生長素
당뇨병%심기경사%신생혈관화,병이성%수체,촉생장소
Diabetes mellitus%Myocardial infarction%Neovascularization,pathologic%Receptors,somatotropin
目的 探讨生长激素促分泌物受体(GHSR)的内源性配体ghrelin对糖尿病大鼠缺血诱导的血管新生障碍的影响及相关机制.方法 选取7～8周龄的SD大鼠,用完全随机化法分为6组:(1)正常对照组,(2)单纯糖尿病组,(3)单纯心肌梗死(MI)组,(4)糖尿病合并MI组,(5)糖尿病合并MI+ ghrelin干预组,(6)糖尿病合并MI+ ghrelin+ GHSR1a特异性拮抗剂D-Lys3-GHRP-6干预组.建立链脲佐菌素(STZ)糖尿病大鼠模型,3个月后结扎冠状动脉左前降支建立急性MI模型.ghrelin干预组大鼠腹腔注射ghrelin(200 μg·kg-1·d-1),ghrelin+ D-Lys3-GHRP-6干预组大鼠腹腔注射ghrelin(200μg·kg-1·d-1)+ D-Lys3-GHRP-6(50 mg· kg-1·d-1),其余组别分别腹腔注射等量生理盐水.4周后超声心动图检测各组大鼠心功能,CD34免疫组织化学检测MI边缘区微血管生成密度(MVD),Masson染色检测MI面积,实时荧光定量-PCR和Western blot分别检测MI边缘区血管内皮细胞生长因子(VEGF)、血管内皮细胞生长因子受体1(Flt-1)和血管内皮细胞生长因子受体2(Flk-1)的mRNA及蛋白表达.结果 (1)与单纯MI组比较,糖尿病合并MI组梗死边缘区MVD[(15.3±1.0)个比(20.7±1.6)个,P＜0.05]、左心室射血分数(LVEF)[(64.2±3.4)％比(81.3±3.8)％,P＜0.01]、左心室短轴缩短率(LVFS)[(31.7±1.1)％比(48.8±3.3)％,P＜0.01]较低,MI面积较大[(55.8±3.1)％比(35.7 ±2.5)％,P＜0.01],梗死边缘区VEGF及其受体Flt-1、Flk-1的基因和蛋白表达差异均有统计学意义(P均＜0.001).(2)与糖尿病合并MI组比较,糖尿病合并MI+ghrelin干预组梗死边缘区MVD[(17.7±1.3)个比(15.3±1.0)个,P＜0.05]、LVEF[(83.9±6.3)％比(64.2±3.4)％,P＜0.001]、LVFS[(44.5±3.1)％比(31.7±1.1)％,P＜0.001]较大,MI面积较低[(35.4±4.37)％比(55.8±3.1)％,P =0.005],梗死边缘区VEGF及其受体Flt-1、Flk-1的基因和蛋白表达差异均有统计学意义(P ＜0.001).ghrelin+ D-Lys3-GHRP-6干预组大鼠MVD、LVEF、LVFS均较ghrelin干预组低(P均＜0.05),MI面积较大[(52.1±1.04)％比(35.4±4.37)％,P=0.02],梗死边缘区VEGF及其受体Flt-1、Flk-1基因与蛋白表达的效应较高(P均＜0.01).结论 糖尿病合并MI大鼠心肌梗死边缘区MVD和心功能较单纯MI大鼠低,MI面积大,ghrelin可能通过调控GHSR1a依赖的VEGF及其受体Flt-1、Flk-1基因和蛋白表达来提高糖尿病MI大鼠梗死边缘区MVD,进一步减少其梗死面积及改善心功能.
目的 探討生長激素促分泌物受體(GHSR)的內源性配體ghrelin對糖尿病大鼠缺血誘導的血管新生障礙的影響及相關機製.方法 選取7～8週齡的SD大鼠,用完全隨機化法分為6組:(1)正常對照組,(2)單純糖尿病組,(3)單純心肌梗死(MI)組,(4)糖尿病閤併MI組,(5)糖尿病閤併MI+ ghrelin榦預組,(6)糖尿病閤併MI+ ghrelin+ GHSR1a特異性拮抗劑D-Lys3-GHRP-6榦預組.建立鏈脲佐菌素(STZ)糖尿病大鼠模型,3箇月後結扎冠狀動脈左前降支建立急性MI模型.ghrelin榦預組大鼠腹腔註射ghrelin(200 μg·kg-1·d-1),ghrelin+ D-Lys3-GHRP-6榦預組大鼠腹腔註射ghrelin(200μg·kg-1·d-1)+ D-Lys3-GHRP-6(50 mg· kg-1·d-1),其餘組彆分彆腹腔註射等量生理鹽水.4週後超聲心動圖檢測各組大鼠心功能,CD34免疫組織化學檢測MI邊緣區微血管生成密度(MVD),Masson染色檢測MI麵積,實時熒光定量-PCR和Western blot分彆檢測MI邊緣區血管內皮細胞生長因子(VEGF)、血管內皮細胞生長因子受體1(Flt-1)和血管內皮細胞生長因子受體2(Flk-1)的mRNA及蛋白錶達.結果 (1)與單純MI組比較,糖尿病閤併MI組梗死邊緣區MVD[(15.3±1.0)箇比(20.7±1.6)箇,P＜0.05]、左心室射血分數(LVEF)[(64.2±3.4)％比(81.3±3.8)％,P＜0.01]、左心室短軸縮短率(LVFS)[(31.7±1.1)％比(48.8±3.3)％,P＜0.01]較低,MI麵積較大[(55.8±3.1)％比(35.7 ±2.5)％,P＜0.01],梗死邊緣區VEGF及其受體Flt-1、Flk-1的基因和蛋白錶達差異均有統計學意義(P均＜0.001).(2)與糖尿病閤併MI組比較,糖尿病閤併MI+ghrelin榦預組梗死邊緣區MVD[(17.7±1.3)箇比(15.3±1.0)箇,P＜0.05]、LVEF[(83.9±6.3)％比(64.2±3.4)％,P＜0.001]、LVFS[(44.5±3.1)％比(31.7±1.1)％,P＜0.001]較大,MI麵積較低[(35.4±4.37)％比(55.8±3.1)％,P =0.005],梗死邊緣區VEGF及其受體Flt-1、Flk-1的基因和蛋白錶達差異均有統計學意義(P ＜0.001).ghrelin+ D-Lys3-GHRP-6榦預組大鼠MVD、LVEF、LVFS均較ghrelin榦預組低(P均＜0.05),MI麵積較大[(52.1±1.04)％比(35.4±4.37)％,P=0.02],梗死邊緣區VEGF及其受體Flt-1、Flk-1基因與蛋白錶達的效應較高(P均＜0.01).結論 糖尿病閤併MI大鼠心肌梗死邊緣區MVD和心功能較單純MI大鼠低,MI麵積大,ghrelin可能通過調控GHSR1a依賴的VEGF及其受體Flt-1、Flk-1基因和蛋白錶達來提高糖尿病MI大鼠梗死邊緣區MVD,進一步減少其梗死麵積及改善心功能.
목적 탐토생장격소촉분비물수체(GHSR)적내원성배체ghrelin대당뇨병대서결혈유도적혈관신생장애적영향급상관궤제.방법 선취7～8주령적SD대서,용완전수궤화법분위6조:(1)정상대조조,(2)단순당뇨병조,(3)단순심기경사(MI)조,(4)당뇨병합병MI조,(5)당뇨병합병MI+ ghrelin간예조,(6)당뇨병합병MI+ ghrelin+ GHSR1a특이성길항제D-Lys3-GHRP-6간예조.건립련뇨좌균소(STZ)당뇨병대서모형,3개월후결찰관상동맥좌전강지건립급성MI모형.ghrelin간예조대서복강주사ghrelin(200 μg·kg-1·d-1),ghrelin+ D-Lys3-GHRP-6간예조대서복강주사ghrelin(200μg·kg-1·d-1)+ D-Lys3-GHRP-6(50 mg· kg-1·d-1),기여조별분별복강주사등량생리염수.4주후초성심동도검측각조대서심공능,CD34면역조직화학검측MI변연구미혈관생성밀도(MVD),Masson염색검측MI면적,실시형광정량-PCR화Western blot분별검측MI변연구혈관내피세포생장인자(VEGF)、혈관내피세포생장인자수체1(Flt-1)화혈관내피세포생장인자수체2(Flk-1)적mRNA급단백표체.결과 (1)여단순MI조비교,당뇨병합병MI조경사변연구MVD[(15.3±1.0)개비(20.7±1.6)개,P＜0.05]、좌심실사혈분수(LVEF)[(64.2±3.4)％비(81.3±3.8)％,P＜0.01]、좌심실단축축단솔(LVFS)[(31.7±1.1)％비(48.8±3.3)％,P＜0.01]교저,MI면적교대[(55.8±3.1)％비(35.7 ±2.5)％,P＜0.01],경사변연구VEGF급기수체Flt-1、Flk-1적기인화단백표체차이균유통계학의의(P균＜0.001).(2)여당뇨병합병MI조비교,당뇨병합병MI+ghrelin간예조경사변연구MVD[(17.7±1.3)개비(15.3±1.0)개,P＜0.05]、LVEF[(83.9±6.3)％비(64.2±3.4)％,P＜0.001]、LVFS[(44.5±3.1)％비(31.7±1.1)％,P＜0.001]교대,MI면적교저[(35.4±4.37)％비(55.8±3.1)％,P =0.005],경사변연구VEGF급기수체Flt-1、Flk-1적기인화단백표체차이균유통계학의의(P ＜0.001).ghrelin+ D-Lys3-GHRP-6간예조대서MVD、LVEF、LVFS균교ghrelin간예조저(P균＜0.05),MI면적교대[(52.1±1.04)％비(35.4±4.37)％,P=0.02],경사변연구VEGF급기수체Flt-1、Flk-1기인여단백표체적효응교고(P균＜0.01).결론 당뇨병합병MI대서심기경사변연구MVD화심공능교단순MI대서저,MI면적대,ghrelin가능통과조공GHSR1a의뢰적VEGF급기수체Flt-1、Flk-1기인화단백표체래제고당뇨병MI대서경사변연구MVD,진일보감소기경사면적급개선심공능.
Objective To investigate the effects and related mechanisms of ghrelin on myocardial neovascularization in diabetic rats with experimental myocardial infarction (MI).Methods Adult male SD rats were divided into six groups (n =20 each group):control,diabetes mellitus (DM),MI,DM + MI,DM +MI + ghrelin,DM + MI + ghrelin + D-Lys3-GHRP-6 (GHSRla inhibitor).DM was induced by streptozotocin (STZ,60 mg/kg),3 months later,MI was induced by left anterior descending artery ligation in DM rats.DM + MI + ghrelin group received ghrelin 200 μg · kg-1 · d-1 and DM + MI + ghrelin + D-Lys3-GHRP-6 group received ghrelin 200 μg · kg-1 · d-1 and D-Lys3-GHRP-6 50 mg · kg-1 · d-1 for 4 weeks.Then,cardiac function was measured by echocardiography,microvascular density (MVD) was measured by CD34 immunohistochemistry,myocardial infarct size was determined by Masson staining,the mRNA and protein expressions of vascular endothelial growth factor (VEGF) and receptors Flk-1,Flt-1 were detected by real-time PCR and Western-blot,respectively.Results Compared with MI group,MVD(15.3 ± 1.0 vs.20.7 ± 1.6,P ＜ 0.05),left ventricular ejection fraction (LVEF) ((64.2 ± 3.4) ％ vs.(81.3 ±3.8) ％,P ＜ 0.01),left ventricular fractional shortening (LVFS) ((31.7 ± 1.1) ％ vs.(48.8 ± 3.3) ％,P ＜ 0.01) and the mRNA and protein expression of VEGF,Flk-1 and Flt-1 (P ＜ 0.01) were reduced,while myocardial infarct size ((55.8 ± 3.1) ％ vs.(35.7 ± 2.5) ％,P ＜ 0.01) was increased in DM + MI group.These effects were partly reversed in DM + MI + ghrelin group and the beneficial effects of ghrelin were partly abolished by D-Lys3-GHRP-6 (all P ＜ 0.05).Conclusions Our results demonstrate that ghrelin could improve microvascular density,cardiac function,and reduce myocardial infarct size of diabetic rats with myocardial infarction via modulating GHSR1 a-mediated expressions of VEGF,Flk-1 and Flt-1.
