Separation of the ascidian blood cells containing a large amount of vanadium and their accumulating mechanism of this element

众所周知，海鞘在其组织中积累了非常大量的钒。因此，它们被认为是检验钒功能的最佳材料。我们已经测定了15种孤立海鞘的钒含量，主要是通过中子活化分析。血细胞中的钒含量最高(21微克钒/毫克干重)，但血细胞一般分为7种类型。这些细胞类型中的哪一种参与了海水中钒的积累是有争议的。因此，本项目旨在利用一种新的技术在Ficoll密度梯度中确定每种血细胞中的钒的分布，然后对钒进行中子活化分析和氧钒离子的ESR谱。因此，尽管可以获得一种桑椹细胞亚群，最初被称为钒细胞，但它含有少量的钒。相反，分布在Ficoll密度梯度最低层的印章环细胞亚群含有最高的钒含量(每1000个细胞含钒7 ng)。因此，已发现印章环细胞是在阿霍多里腹水中积累钒的初级血细胞。此外，ESR谱还表明，在细胞中检测到氧化态IV的钒离子(&lt；VO^(2+)&gt；)，并通过其供氧体与一些低分子结合。

Ascidians are known to accumulate very large amounts of vanadium within their tissues. They are, therfore, thought to be the best material to use in order to examine the function of vanadium. We have already determined the vanadium contents of 15 species of solitary ascidians, mainly by neutron activation analysis. The highest value of vanadium was obtained from blood cells of Asicia ahodori (21 ug vanadium/mg dry meight).However, the blood cells are generally classified into 7 types in this species. Which of these cell types are involved in the accumulation of vanadium from sea water is controversial.The present project was, therefore, designed to determine the distribution of vanadium in each of these blood cell types using a new technique for cell fractionation in Ficoll density gradients, followed by neutron activation analysis for vanadium and ESR spectra of oxovanadium ion.Consequently, although a subpopulation of morula cells, originally termed vanadocytes, could be obtained with above 90% purity, it contained little vanadium. Instead of it, a subpopulation of signet ring cells distributed in the lowest layer in the Ficoll density gradients contained the highest amount of vanadium (7 ng vanadium/1000 cells). Thus, it has been found that the signet ring cells are primary blood cells that accumulate vanadium in Ascidia ahodori. Moreover, ESR spectra have revelaed that vanadyl ion ( <VO^(2+)> ), vanadium in oxidation state IV, was detected in the cells and bound with some low-molecules through its oxygen donors.