• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>American Journal of Physiology >Caffeine sensitivity of native RyR channels from normal and malignant hyperthermic pigs: effects of a DHPR II-III loop peptide.
【24h】

Caffeine sensitivity of native RyR channels from normal and malignant hyperthermic pigs: effects of a DHPR II-III loop peptide.

机译：来自正常和恶性高热猪的天然RyR通道的咖啡因敏感性：DHPR II-III环肽的作用。

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Enhanced sensitivity to caffeine is part of the standard tests for susceptibility to malignant hyperthermia (MH) in humans and pigs. The caffeine sensitivity of skeletal muscle contraction and Ca(2+) release from the sarcoplasmic reticulum is enhanced, but surprisingly, the caffeine sensitivity of purified porcine ryanodine receptor Ca(2+)-release channels (RyRs) is not affected by the MH mutation (Arg(615)Cys). In contrast, we show here that native malignant hyperthermic pig RyRs (incorporated into lipid bilayers with RyR-associated lipids and proteins) were activated by caffeine at 100- to 1000-fold lower concentrations than native normal pig RyRs. In addition, the results show that the mutant ryanodine receptor channels were less sensitive to high-affinity activation by a peptide (C(S)) that corresponds to a part of the II-III loop of the skeletal dihydropyridine receptor (DHPR). Furthermore, subactivating concentrations of peptide C(S) enhanced the response of normal pig and rabbit RyRs to caffeine. In contrast, the caffeine sensitivity of MH RyRs was not enhanced by the peptide. These novel results showed that in MH-susceptible pig muscles 1). the caffeine sensitivity of native RyRs was enhanced, 2). the sensitivity of RyRs to a skeletal II-III loop peptide was depressed, and 3). an interaction between the caffeine and peptide C(S) activation mechanisms seen in normal RyRs was lost.
机译：对咖啡因的敏感性增强是人和猪对恶性高热（MH）敏感性的标准测试的一部分。咖啡因敏感性的骨骼肌收缩和Ca（2+）从肌质网释放，但令人惊讶的是，纯化的猪ryanodine受体Ca（2 +）-释放通道（RyRs）的咖啡因敏感性不受MH突变的影响（Arg（615）Cys）。相反，我们在这里显示咖啡因激活了天然恶性高热猪RyRs（与脂质RyR相关的脂质和蛋白质结合到脂质双层中）的浓度比天然正常猪RyRs低100到1000倍。此外，结果表明，突变体ryanodine受体通道对高亲和性激活的肽（C（S））的敏感性较低，该肽对应于骨架二氢吡啶受体（DHPR）的II-III环的一部分。此外，亚激活浓度的肽C（S）增强了正常猪和兔子RyR对咖啡因的反应。相反，该肽并未增强MH RyRs的咖啡因敏感性。这些新颖的结果表明，在MH敏感的猪肌肉中1）。天然RyRs的咖啡因敏感性增强，2）。 RyRs对骨骼II-III环肽的敏感性降低，3）。咖啡因和正常RyRs中所见的肽C（S）激活机制之间的相互作用消失了。

著录项

相似文献

  • 外文文献
  • 中文文献
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号