HEART INDUCTION - DISTRIBUTION OF ACTIVE FACTORS IN NEWT ENDODERM
HEART INDUCTION - DISTRIBUTION OF ACTIVE FACTORS IN NEWT ENDODERM
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DOI：
10.1002/jez.1401750306
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发表时间：
1970-01-01
影响因子：
--
通讯作者：
FULLILOVE, SL
中科院分区：
文献类型：
--
作者：
FULLILOVE, SL
将来自蝾螈（Taricha torosa）的早期神经胚的假定心脏中胚层与来自胚胎的五个不同区域的内胚层在外植体中组合，以研究诱导心脏形成的能力在内胚层中的分布。最终形成跳动的心脏组织的这种培养物的百分比，以及在这样做之前培养的平均天数，与单独诱导推定心脏中胚层建立的对照水平相比，发现诱导心脏的能力广泛分布，并且在前内胚层中最强。心脏形成反应仅由通常位于假定心脏中胚层下面的内胚层加速，并且该内胚层保留其诱导能力进入尾芽阶段。其他前内胚层是一个强大的心脏感应器，但行动较慢。后内胚层不仅不能促进心脏的形成，而且在少数反应的情况下，能延长心脏收缩开始前的培养时间，而紧接在假定心脏中胚层后面的中胚层也能被诱导形成搏动组织。然而，与假定的心脏中胚层相比，在收缩开始之前要经过更长的时间。由于靠近通常位于心脏下方的内胚层具有诱导心脏的实质性能力，因此覆盖这些区域的中胚层经历一定程度的心脏诱导。正常情况下，受影响的中胚层的这些区域对心脏没有贡献，但在改变的条件下，它们可以。心脏电位的这一扩展的中胚层区域是心脏“场”。心野的存在和范围似乎是内胚层中心脏诱导活性分布的结果。
Presumptive heart mesoderm from early neurulae of the newt,Taricha torosa, was combined in explants with endoderm from five different regions of the embryo to study the distribution in the endoderm of the capability to induce heart formation.The percentages of such cultures that ultimately formed beating heart tissue, and the average numbers of days in culture before doing so, are compared with control levels established by explanting presumptive heart mesoderm alone.The ability to induce hearts is found to be broadly distributed and to be strongest in anterior endoderm. The heart‐forming response is accelerated only by the endoderm normally underlying the presumptive heart mesoderm, and this endoderm retains its inductive capability into tailbud stages. Other anterior endoderm is a powerful heart inductor but acts more slowly. Posterior endoderm not only did not promote heart formation, but also increased the time in culture before the beginning of contraction in the few responding cases.Mesoderm immediately posterior to the presumptive heart mesoderm can also be induced to form beating tissue. However, compared to presumptive heart mesoderm, a much longer time elapses before contractions begin. Since endoderm near that which normally underlies the heart has substantial ability to induce heart, the mesoderm overlying these regions experiences some measure of heart induction. Normally these regions of affected mesoderm do not contribute to the heart, but under altered conditions they can. This extended mesodermal area of heart potential is the heart “field.” The existence and extent of the heart field appears to be a result of the distribution of heart‐inducing activity in the endoderm.