Objectives To investigate the effects of β2-adrenergic antagonist on cytosolic Ca^2 ＋ （[Ca^2＋ ]i） in ventricular myocytes from infarcted rat heart. Methods A ligature was placed around left anterior descending co...Objectives To investigate the effects of β2-adrenergic antagonist on cytosolic Ca^2 ＋ （[Ca^2＋ ]i） in ventricular myocytes from infarcted rat heart. Methods A ligature was placed around left anterior descending coronary artery of rat hearts. Rats in the control group were sham-operated. Cardiomyocytes were dissociated at two, four, eight weeks after myocardial infarction （MI） and [Ca^2＋]i was measured via fura-2 fluorescence. The response of cardiomyocytes to isoproterenol in presence or absence of betal-adrenergic antagonist atenolol, beta2-adrenergic antagonist ICI118, 551 or non-selective β1, 2- adrenergic antagonists propranolol was examined. Results The followings were found that ICI 118, 551 had no significant effects on the rise of [Ca^2＋]i induced by isoproterenol in normal ventricular myocytes （P 〉 0.05）, ICI118, 551 only significantly attenuated the rise of [Ca^2＋]i induced by isoproterenol at four weeks and eight weeks after MI （24.5%±5.7% vs 57.8% ± 13.2%, P〈 0.01; 12.2%±7.9% vs 44.6%±11.3%, P〈 0.01）. Atenolol had suppressive effects only in the control group and the post-MI group of two weeks （P 〈 0.05）, and propranolol had suppressive effects in the control and all the three post-MI groups （P 〈 0.01）. Conclusions Beta2-adrenergic antagonist ICI118, 551 may exert negative effects on Ca^2＋ overload initiated by sympathetic stimulation after MI.展开更多
目的:探讨1-磷酸鞘氨醇(S1P)不同受体亚型(S1P1、S1P2、S1P3)在大鼠心肌梗死后心室重塑过程中的变化差异。方法:通过结扎大鼠左冠状动脉前降支,建立大鼠心肌梗死模型,在心肌梗死后1、4、8周,采用实时荧光定量PCR的方法,分别检测心脏非...目的:探讨1-磷酸鞘氨醇(S1P)不同受体亚型(S1P1、S1P2、S1P3)在大鼠心肌梗死后心室重塑过程中的变化差异。方法:通过结扎大鼠左冠状动脉前降支,建立大鼠心肌梗死模型,在心肌梗死后1、4、8周,采用实时荧光定量PCR的方法,分别检测心脏非梗死区、梗死区、正常对照心肌组织S1P1、S1P2、S1P3的m RNA相对表达。结果:心梗后心室重塑阶段,S1P1 m RNA的表达水平在非梗死区与梗死区的下降程度不一致,1周组非梗死区与正常对照组比较无统计学差异,而在梗死区2组间差异有统计学意义(P<0.05),在梗死区降低趋势更为明显。S1P2 m RNA在术后各组的非梗死区与正常对照心肌之间的表达比较,变化无统计学意义,且各时间点之间无差异,而在梗死区其表达变化较为显著(P<0.01)。S1P3 m RNA在心梗后1周表达显著增强(P<0.01),4周表达出现降低,这种表达抑制在梗死区更为明显(P<0.01和P<0.05)。结论:心室重塑阶段的S1P1、S1P2、S1P3 m RNA表达在非梗死区与梗死区变化不同步且各有特点,这种差异表达可能在心肌梗死后心室重塑过程中有重要意义。展开更多
目的探讨厄贝沙坦联合缺血后适应对2型糖尿病大鼠缺血再灌注损伤早期心肌纤维化及心室重构的影响及机制。方法选取SD大鼠40只,建立2型糖尿病大鼠模型,随机分为4组(n=10):1假手术组;2缺血再灌注对照组(对照组);3缺血后适应组(Post组);4...目的探讨厄贝沙坦联合缺血后适应对2型糖尿病大鼠缺血再灌注损伤早期心肌纤维化及心室重构的影响及机制。方法选取SD大鼠40只,建立2型糖尿病大鼠模型,随机分为4组(n=10):1假手术组;2缺血再灌注对照组(对照组);3缺血后适应组(Post组);4厄贝沙坦后处理+缺血后适应组(Eba+Post组)。检测各组大鼠血清肌钙蛋白c Tn T以及心肌酶CK-MB、血清AT1受体自身抗体及心肌AT1R m RNA的表达;HE染色和电镜测定大鼠心肌间质纤维化及心肌炎性水平,以及各组大鼠心重指数和心肌胶原蛋白含量。结果 Post组CK-MB和c Tn T水平均低于对照组(均P<0.05),Eba+Post组CK-MB和c Tn T水平低于Post组,P<0.05;Post组及Eba+Post组抗AT1R受体阳性率分别为30%(3/10)和20%(2/10),明显低于对照组50%(5/10),P<0.05;Post组、Eba+Post组大鼠治疗后AT1R m RNA的表达明显减少,均明显低于对照组,P<0.05,与Post组相比,Eba+Post组AT1R m RNA的表达显著减少,P<0.05;HE染色切片及电镜检查显示,Post组、Eba+Post组心肌超微结构的改善明显,Eba+Post组心肌炎症及心肌纤维化的改善效果更为明显;对照组、Post组及Eba+Post组心重指数及心肌胶原蛋白含量较假手术组升高,治疗组上述指标均显著下降,Eba+Post组心重指数及心肌胶原蛋白含量较Post组降低,P<0.05。结论在高血糖大鼠心肌缺血再灌注条件下,ARB药物后处理对心肌缺血后适应有协同保护作用,其机制可能与调节AngⅡ、AT1R的水平有关,可改善早期心肌纤维化,减轻早期心室重构。展开更多
文摘Objectives To investigate the effects of β2-adrenergic antagonist on cytosolic Ca^2 ＋ （[Ca^2＋ ]i） in ventricular myocytes from infarcted rat heart. Methods A ligature was placed around left anterior descending coronary artery of rat hearts. Rats in the control group were sham-operated. Cardiomyocytes were dissociated at two, four, eight weeks after myocardial infarction （MI） and [Ca^2＋]i was measured via fura-2 fluorescence. The response of cardiomyocytes to isoproterenol in presence or absence of betal-adrenergic antagonist atenolol, beta2-adrenergic antagonist ICI118, 551 or non-selective β1, 2- adrenergic antagonists propranolol was examined. Results The followings were found that ICI 118, 551 had no significant effects on the rise of [Ca^2＋]i induced by isoproterenol in normal ventricular myocytes （P 〉 0.05）, ICI118, 551 only significantly attenuated the rise of [Ca^2＋]i induced by isoproterenol at four weeks and eight weeks after MI （24.5%±5.7% vs 57.8% ± 13.2%, P〈 0.01; 12.2%±7.9% vs 44.6%±11.3%, P〈 0.01）. Atenolol had suppressive effects only in the control group and the post-MI group of two weeks （P 〈 0.05）, and propranolol had suppressive effects in the control and all the three post-MI groups （P 〈 0.01）. Conclusions Beta2-adrenergic antagonist ICI118, 551 may exert negative effects on Ca^2＋ overload initiated by sympathetic stimulation after MI.
文摘目的:探讨1-磷酸鞘氨醇(S1P)不同受体亚型(S1P1、S1P2、S1P3)在大鼠心肌梗死后心室重塑过程中的变化差异。方法:通过结扎大鼠左冠状动脉前降支,建立大鼠心肌梗死模型,在心肌梗死后1、4、8周,采用实时荧光定量PCR的方法,分别检测心脏非梗死区、梗死区、正常对照心肌组织S1P1、S1P2、S1P3的m RNA相对表达。结果:心梗后心室重塑阶段,S1P1 m RNA的表达水平在非梗死区与梗死区的下降程度不一致,1周组非梗死区与正常对照组比较无统计学差异,而在梗死区2组间差异有统计学意义(P<0.05),在梗死区降低趋势更为明显。S1P2 m RNA在术后各组的非梗死区与正常对照心肌之间的表达比较,变化无统计学意义,且各时间点之间无差异,而在梗死区其表达变化较为显著(P<0.01)。S1P3 m RNA在心梗后1周表达显著增强(P<0.01),4周表达出现降低,这种表达抑制在梗死区更为明显(P<0.01和P<0.05)。结论:心室重塑阶段的S1P1、S1P2、S1P3 m RNA表达在非梗死区与梗死区变化不同步且各有特点,这种差异表达可能在心肌梗死后心室重塑过程中有重要意义。
文摘目的探讨厄贝沙坦联合缺血后适应对2型糖尿病大鼠缺血再灌注损伤早期心肌纤维化及心室重构的影响及机制。方法选取SD大鼠40只,建立2型糖尿病大鼠模型,随机分为4组(n=10):1假手术组;2缺血再灌注对照组(对照组);3缺血后适应组(Post组);4厄贝沙坦后处理+缺血后适应组(Eba+Post组)。检测各组大鼠血清肌钙蛋白c Tn T以及心肌酶CK-MB、血清AT1受体自身抗体及心肌AT1R m RNA的表达;HE染色和电镜测定大鼠心肌间质纤维化及心肌炎性水平,以及各组大鼠心重指数和心肌胶原蛋白含量。结果 Post组CK-MB和c Tn T水平均低于对照组(均P<0.05),Eba+Post组CK-MB和c Tn T水平低于Post组,P<0.05;Post组及Eba+Post组抗AT1R受体阳性率分别为30%(3/10)和20%(2/10),明显低于对照组50%(5/10),P<0.05;Post组、Eba+Post组大鼠治疗后AT1R m RNA的表达明显减少,均明显低于对照组,P<0.05,与Post组相比,Eba+Post组AT1R m RNA的表达显著减少,P<0.05;HE染色切片及电镜检查显示,Post组、Eba+Post组心肌超微结构的改善明显,Eba+Post组心肌炎症及心肌纤维化的改善效果更为明显;对照组、Post组及Eba+Post组心重指数及心肌胶原蛋白含量较假手术组升高,治疗组上述指标均显著下降,Eba+Post组心重指数及心肌胶原蛋白含量较Post组降低,P<0.05。结论在高血糖大鼠心肌缺血再灌注条件下,ARB药物后处理对心肌缺血后适应有协同保护作用,其机制可能与调节AngⅡ、AT1R的水平有关,可改善早期心肌纤维化,减轻早期心室重构。
