Godin I
Anat Embryol (Berl). 1986;173(3):393-9. doi: 10.1007/BF00318924.
The notochord of amphibian anuran embryos contains catecholamines during the early developmental stages. In order to determine if these catecholamines are synthesized in situ, the development of their specific histofluorescence was investigated in the notochord alone or the notochord combined with the lateral somitic mesoderm, both explanted at the neurula stage and cultivated in vitro or implanted into the ventral part of early neurulae endoderm. The histofluorescence evolution, on the other hand, was investigated in the notochord alone or combined with myotomes, both explanted after the beginning of catecholamine biosynthesis and cultivated in vitro for one hour, in order to determine the effect of explantation and culture on the accumulation of notochordal catecholamines. The comparative study of catecholamine histofluorescence in these different samples shows that: the notochord is able to perform, on its own, the entire biosynthesis of the catecholamines stored in it during the early developmental stages. The catecholamines generated from isolated notochords tend to diffuse into the culture medium, probably due to a deficiency in the vesicular storage system usually found in the catecholamine-synthesizing cells. This loss of catecholamines in vitro can be obviated by the presence round the notochord of any embryonal tissue (somitic mesoderm, endoderm).
两栖类无尾目胚胎的脊索在发育早期阶段含有儿茶酚胺。为了确定这些儿茶酚胺是否在原位合成，研究了单独脊索或脊索与体节外侧中胚层结合时其特异性组织荧光的发育情况，二者均在神经胚期取出并进行体外培养，或将其植入早期神经胚内胚层的腹侧部分。另一方面，研究了单独脊索或与肌节结合时的组织荧光演变情况，二者均在儿茶酚胺生物合成开始后取出并进行体外培养1小时，以确定取出和培养对脊索儿茶酚胺积累的影响。对这些不同样本中儿茶酚胺组织荧光的比较研究表明：脊索能够自行完成早期发育阶段储存于其中的儿茶酚胺的整个生物合成过程。从分离的脊索产生的儿茶酚胺往往会扩散到培养基中，这可能是由于通常在儿茶酚胺合成细胞中发现的囊泡储存系统存在缺陷所致。脊索周围存在任何胚胎组织（体节中胚层、内胚层）都可以避免体外儿茶酚胺的这种损失。
