摘要
应用Ｌａｎｇｅｎｄｏｒｆｆ灌流方法，分离培养成年大鼠心肌细胞（ ＭＣ），并借助同位素标记的底物掺入法，观察在不同处理因素下，洛沙坦（Ｌｏｓ）对大鼠梗塞ＭＣ的ＲＮＡ（１４Ｃ－ＵＲ）的蛋白质（３Ｈ－Ｌｅｕ）合成率的影响。结果发现，在相同浓度的Ａｎｇ （１０－７ｍｏｌ／Ｌ）的作用下，心肌梗塞对照组（ＣＭＩ）的ＭＣ，其１４Ｃ－ＵＲ和３Ｈ－Ｌｅｕ掺入率均显著高于假手术（ＳＯ）组（Ｐ＜０．０５）：而两干预组（ＭＬ＋Ｌｏｓ组和ＭＩ＋Ｃａｐ组）的ＭＣ，其ＲＮ Ａ和蛋白质合成速率与 ＳＯ组无差异。 Ａｎｇ 的上述作用，可分别被 ＡＴ１受体阻滞剂 Ｌｏｓ、 Ａｕｇ 拮抗剂（１．８Ａｎｇ ）和血管紧张素抗肽（ Ａｎｇ－ＡＰ）充全阻断。提示，洛沙坦通过阻断 Ａｎｇ 对非梗塞区 ＭＣ的作用，抑制ＭＣ的 ＲＮＡ、蛋白质合成；长期应用（ ６周） Ｌｏｓ可阻抑 ＭＩ后心肌细胞肥大和降低其对 Ａｎｇ 的反应性。
With the Langendorff infusion and the isotope-labeled substrate uptake, we investigated the mechanism of losartan on the isolated myocytes from myocardium-infarcted rats. This study showed that the synthesis rates of RNA (14C-UR) and protein (3H-Leu) in MC from control MI group are significantly higher than those from the shamoperated (SO) one treated with the same concentration of Aug , respectively. On the other hand, the uptake rates of 3H-Leu, 14C-UR of MC from MI group treated with losartan or captopril are not significantly different from those of the SO one, respectively. These effects of Aug n on MC are abolished completely by angiotensin receptor antagonist-losartan, angiotensin antagonists-1.8 Aug and angiotensin antipeptide. The findings suggest that losartan could prevent the syntheses of RNA and protein in the MC treated with Aug ; Losartan could reduced the myocardial hypertrophy and the responsiveness of Aug on the MC from uninfarcted area.
出处
《基础医学与临床》
CSCD
2000年第4期42-44,47,共4页
Basic and Clinical Medicine
基金
国家自然科学基金!( No.39270315)
"八五"攻关资助!( No.85-195-03-02)
