Ryanodine receptor expression in embryonic avian cardiac muscle.
Ryanodine receptor expression in embryonic avian cardiac muscle.
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Ryanodine 受体在胚胎禽心肌中的表达。
DOI：
10.1006/dbio.1993.1041
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发表时间：
1993
影响因子：
2.7
通讯作者：
Trumble,WR
中科院分区：
文献类型：
--
作者：
Dutro,SM;Airey,JA;Beck,CF;Sutko,JL;Trumble,WR
心脏兰尼碱受体充当肌浆网钙释放通道，并有助于心脏收缩所需的胞质钙的增加。我们研究了鸟类心脏胚胎发育过程中兰尼碱受体的存在和寡聚形式。使用抗受体单克隆抗体结合[3H]兰尼碱结合，在成人和发育第4至20天的胚胎心脏组织中鉴定出兰尼碱受体的单一亚型。蔗糖密度梯度沉降分析和[3H]兰尼碱结合的结果表明，心脏兰尼碱受体在成体和发育第6天的胚胎中均以四聚体形式存在。在胚胎发育第4天和第5天观察到的心脏中特异性[3H]ryanodine结合也表明存在四聚体受体蛋白。尽管心脏在胚胎发育的大约 33-38 小时（第 1.5 天）开始跳动，但在胚胎第 4 天之前，我们无法使用生化或免疫学技术检测到心脏兰尼碱受体。早在汉堡和汉密尔顿第 15-19 阶段（胚胎第 3 天），就发现兰尼碱可以改变完整心脏的变时状态，这表明受体蛋白可能存在于参与起搏器活动的有限细胞子集中。非常早期的胚胎。胚胎第 4 天后，兰尼定还对胚胎心脏产生负性肌力作用。我们的结果表明，从胚胎发育第4天到第20天，禽类心肌中存在单一的兰尼碱受体亚型，并且兰尼碱受体呈现出能够形成功能性钙释放通道的四聚体结构，该通道早在胚胎第4天就参与兴奋-收缩耦合。此外，兰尼碱受体相关功能可能作为非常早期胚胎心脏中变时效应的决定因素。
The cardiac ryanodine receptor serves aa a sarcoplasmic reticulum calcium release channel and contributes to the rise in cytosolic calcium necessary for contraction of the heart. We have investigated the presence and oligomeric form of the ryanodine receptor during embryonic development of the avian heart. A single isoform of the ryanodine receptor was identified both in adult and in embryonic cardiac tissue from Days 4 to 20 of development, using anti-receptor monoclonal antibodies in conjunction with [3H]ryanodine binding. The results of sucrose density gradient sedimentation analysis and [3H]ryanodine binding indicated that the cardiac ryanodine receptor is present in a tetrameric form in both the adult and embryos at Day 6 of development. The observation of specific [3H]ryanodine binding in hearts from Days 4 and 5 of embryonic development also indicates the presence of a tetrameric receptor protein. Although the heart begins to beat at approximately 33-38 hr (Day 1.5) of embryonic development, we were unable to detect the cardiac ryanodine receptor, using biochemical or immunological techniques, prior to Embryonic Day 4. Ryanodine was found to alter the chronotropic state of intact hearts as early as Hamburger and Hamilton stages 15-19 (Embryonic Day 3) suggesting that receptor protein may be present in a limited subset of cells involved in pacemaker activity in the very early embryo. After Embryonic Day 4, ryanodine also exerted a negative inotropic effect on embryonic hearts. Our results suggest that a single isoform of the ryanodine receptor is present from Day 4 to Day 20 of embryonic development in avian cardiac muscle and that the ryanodine receptor assumes a tetrameric structure capable of forming a functional calcium release channel that participates in excitation-contraction coupling as early as Embryonic Day 4. In addition, a ryanodine receptor-related function may serve as a determinant of chronotropic effects in the very early embryonic heart.