Core C

核心C

• 批准号: 7075001
• 负责人: Sheila Muldoon
• 金额: $ 13.6万
• 依托单位: BRIGHAM AND WOMEN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-04-14 至 2011-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7075001
• 关键词: anesthetics; caffeine; halothane; muscle; phenotype; striated muscles; surgery

Malignant Hyperthermia (MH) is an autosomal dominant disorder of skeletal muscle that causes a life threatening reaction following administration of commonly used inhalational anesthetics such as halothane, or the depolarizing muscle relaxant succinylcholine. Administration of the anesthetics during surgery causes an altered release of calcium from the sarcoplasmic reticulum (SR) through the ryanodine receptor (RYR1), which in turn induces a cascade of biochemical events that culminates in a nypermetabolic state (fulminant episode) with hyperthermia. If not treated, promptly by withdrawing the anesthetic and administering dantrolene (a drug that inhibits release of Ca++ from the SR) mortality can be as great as 70%. Because most MH individuals appear normal and susceptibility becomes apparent only after exposure to anesthetics, identifying MH susceptible individuals prior to surgery is difficult requiring muscle biopsy and measurements of the contractile sensitivity to RYR1 agonists caffeine and halothane. The caffeine-halothane contracture test (CHCT) phenotypes patients as MHS (susceptible) or MHN (normal). The CHCT has a sensitivity of 93% and specificity of 78%. USUHS has performed over 400 CHCT tests on patients. Approximately 50% of patients are diagnosed CHCT positive. Core C will review MH susceptible individuals, probands and family members for clinical histories of adverse responses to anesthetic drugs, phenotype skeletal muscle samples with performance of a CHCT, and genotype CHCT positive patients for causative mutations in RyR1 and the a1s-DHPR genes. They will collect blood samples from these patients a) for mRNA for use in profiling studies, b) to make permanent B-lymphocyte cell lines for physiologic and transcriptional profiling studies, and c) for the isolation of dendritic cells. In addition, they will collect muscle samples to make myoblast cultures to be purified by Core B, and flash freeze discarded muscle samples for transcriptional profiling studies.

恶性高热（MH）是一种常染色体显性骨骼肌疾病 在施用常用药物后会导致危及生命的反应 吸入麻醉剂，例如氟烷或去极化肌肉松弛剂 琥珀酰胆碱。手术期间使用麻醉剂会导致手术发生改变 通过兰尼碱受体从肌浆网 (SR) 释放钙 (RYR1)，进而诱导一系列生化事件，最终导致 高代谢状态（暴发性发作）伴有高热。如果不及时治疗，应及时 撤除麻醉剂并给予丹曲林（一种抑制释放的药物） SR 中的 Ca++）死亡率可高达 70%。因为大多数 MH 个体 表现正常，并且只有在接触麻醉剂后易感性才变得明显， 在手术前识别 MH 易感个体很困难，需要进行肌肉活检 以及对 RYR1 激动剂咖啡因和氟烷的收缩敏感性的测量。 咖啡因-氟烷挛缩试验 (CHCT) 将患者表型为 MHS （易感）或 MHN（正常）。 CHCT 的敏感性为 93%，特异性为 78%。 USUHS 已对患者进行了 400 多次 CHCT 测试。大约50%的患者 诊断为 CHCT 阳性。核心 C 将审查 MH 易感个体、先证者 和家庭成员对麻醉药物不良反应的临床病史， 具有 CHCT 表现的表型骨骼肌样本和基因型 CHCT RyR1 和 a1s-DHPR 基因致病突变呈阳性的患者。他们会 从这些患者身上采集血液样本 a) 用于分析研究的 mRNA，b) 制作永久性 B 淋巴细胞系以进行生理和转录分析 研究，以及c) 用于分离树突状细胞。此外，他们还会收集肌肉 制备成肌细胞培养物的样品由 Core B 纯化，并快速冷冻丢弃 用于转录分析研究的肌肉样本。