Fukuda S
J Embryol Exp Morphol. 1979 Aug;52:49-62.
Hepatogenic potency of the endoderm is detectable in the anterior half of the endoderm of quail embryos older than 2-somite stage when endodermal fragments are cultured with or without heterologous chick mesenchymes, in the coelomic cavity of 3-day chick embryos. On the other hand, the posterior half of the endoderm never has hepatogenic potency. The hepatogenic potency of the endoderm is gradually stabilised with increasing age. However, expression of hepatogenesis can be affected when the endoderm is associated with inductively active digestive tract mesenchymes. Mesenchyme taken from the presumptive cardiac region ('cardiac' mesenchyme) of chick embryos is necessary for the uncommitted anterior endoderm to acquire hepatogenic potency, and this effect is specific for the 'cardiac' mesenchyme. The 'cardiac' mesenchyme, however, fails to induce hepatic epithelium in the allantoic endoderm, which can differentiate heterotypically when cultured in combination with digestive tract mesenchymes. The evidence presented in this study suggests that the effect of 'cardiac' mesenchyme on the acquisition of hepatogenic potency in the endoderm is limited.
当将内胚层片段与或不与异源鸡间充质一起培养于3日龄鸡胚的体腔中时，鹌鹑胚胎2体节期以上内胚层前半部分的内胚层肝细胞生成能力是可检测到的。另一方面，内胚层后半部分从未具有肝细胞生成能力。内胚层的肝细胞生成能力随着年龄增长逐渐稳定。然而，当内胚层与具有诱导活性的消化道间充质相关联时，肝细胞生成的表达可能会受到影响。取自鸡胚预定心脏区域（“心脏”间充质）的间充质对于未分化的前内胚层获得肝细胞生成能力是必需的，并且这种作用对“心脏”间充质具有特异性。然而，“心脏”间充质未能诱导尿囊内胚层形成肝上皮，尿囊内胚层与消化道间充质联合培养时可发生异型分化。本研究提供的证据表明，“心脏”间充质对内胚层获得肝细胞生成能力的作用是有限的。
