目的:观察Β2肾上腺素受体拮抗剂对心肌梗死后心肌细胞胞浆游离CA2+浓度([CA2+]I)的影响。方法:结扎冠状动脉,复制大鼠心肌梗死模型。随机分为心肌梗死后2、4、8周组,正常对照组作假手术。分离大鼠心肌细胞,每组大鼠制备20份样品,再随...目的:观察Β2肾上腺素受体拮抗剂对心肌梗死后心肌细胞胞浆游离CA2+浓度([CA2+]I)的影响。方法:结扎冠状动脉,复制大鼠心肌梗死模型。随机分为心肌梗死后2、4、8周组,正常对照组作假手术。分离大鼠心肌细胞,每组大鼠制备20份样品,再随机分为4小组,分别给予Β2受体拮抗剂ICI118,551、Β1受体拮抗剂阿替洛尔、非选择性Β受体拮抗剂普萘洛尔后,用FURA-2荧光技术测定心肌细胞[C2+]I。结果:心肌梗死后4、8周,ICI118, 551组心肌细胞[CA2+]I增幅显著低于异丙肾上腺素组(24.5%±5.7% VS 57.8%±13.2%,P<0.01;12.2%±7.9% VS 44.6%±11.3%, P<0.01);正常对照组和心肌梗死后2周,上述两组心肌细胞[CA2+]I增幅无显著差异(P> 0.05)。正常对照组和心肌梗死后2周,阿替洛尔组心肌细胞[CA2+]I增幅显著低于异丙肾上腺素组(P<0.05);正常对照组及心肌梗死后2、4、8周,普萘洛尔组心肌细胞[CA2+]I增幅均显著低于异丙肾上腺素组(P<0.05)。结论:Β2 受体拮抗剂对于有效抑制心肌梗死后交感神经激动引起的心肌细胞内钙超载可能起重要作用。展开更多
adrenergic receptor is the third subtype of β-adrenergic receptors. The genetic structure and pharmacological property of β 3-adrenergic receptor are markedly distinguished from β 1-and β 2-adrenergic receptor sub...adrenergic receptor is the third subtype of β-adrenergic receptors. The genetic structure and pharmacological property of β 3-adrenergic receptor are markedly distinguished from β 1-and β 2-adrenergic receptor subtypes. Recently studies show that myocardial β 3-adrenergic receptor mediates negative inotropic effect through Gi-protein/NO/cGMP pathway, the expression of β 3-adrenergic receptor and negative inotropic effect mediated by β 3-adrenergic receptor are increased in heart failure. However, because of the low expression of β 3-adrenergic receptor in the heart, the actual pathophysiological significance of β 3-adrenergic receptor remains unknown.展开更多
文摘目的:观察Β2肾上腺素受体拮抗剂对心肌梗死后心肌细胞胞浆游离CA2+浓度([CA2+]I)的影响。方法:结扎冠状动脉,复制大鼠心肌梗死模型。随机分为心肌梗死后2、4、8周组,正常对照组作假手术。分离大鼠心肌细胞,每组大鼠制备20份样品,再随机分为4小组,分别给予Β2受体拮抗剂ICI118,551、Β1受体拮抗剂阿替洛尔、非选择性Β受体拮抗剂普萘洛尔后,用FURA-2荧光技术测定心肌细胞[C2+]I。结果:心肌梗死后4、8周,ICI118, 551组心肌细胞[CA2+]I增幅显著低于异丙肾上腺素组(24.5%±5.7% VS 57.8%±13.2%,P<0.01;12.2%±7.9% VS 44.6%±11.3%, P<0.01);正常对照组和心肌梗死后2周,上述两组心肌细胞[CA2+]I增幅无显著差异(P> 0.05)。正常对照组和心肌梗死后2周,阿替洛尔组心肌细胞[CA2+]I增幅显著低于异丙肾上腺素组(P<0.05);正常对照组及心肌梗死后2、4、8周,普萘洛尔组心肌细胞[CA2+]I增幅均显著低于异丙肾上腺素组(P<0.05)。结论:Β2 受体拮抗剂对于有效抑制心肌梗死后交感神经激动引起的心肌细胞内钙超载可能起重要作用。
文摘adrenergic receptor is the third subtype of β-adrenergic receptors. The genetic structure and pharmacological property of β 3-adrenergic receptor are markedly distinguished from β 1-and β 2-adrenergic receptor subtypes. Recently studies show that myocardial β 3-adrenergic receptor mediates negative inotropic effect through Gi-protein/NO/cGMP pathway, the expression of β 3-adrenergic receptor and negative inotropic effect mediated by β 3-adrenergic receptor are increased in heart failure. However, because of the low expression of β 3-adrenergic receptor in the heart, the actual pathophysiological significance of β 3-adrenergic receptor remains unknown.