Wessing A, Zierold K, Schäfer D
Institut für Allgemeine und Spezielle Zoologie, Justus-Liebig-Universität, Deutschland.
Eur J Cell Biol. 1988 Oct;47(1):1-6.
Using electron probe X-ray microanalysis after cryofixation, cryosectioning and freeze-drying we investigated the content of electron-dark vacuoles in the intermediate cell region of the proximal segment of Malpighian tubules in Drosophila larvae. According to this method these vacuoles store sodium and magnesium in a high correlation (r = 0.98) of 5:1 ratio. Phosphorus, potassium and sulfur are also stored. In the intermediate groundplasm surrounding the vacuoles the element content is different from that in the vacuoles. The significance of vacuolar sodium and magnesium storage for the ionic metabolism is unknown. In addition to Na, Mg, P, K and S the vacuoles also contain 3-OH-kynurenine and other fluorochromes. With the pyroantimonate technique intravacuolar precipitates were demonstrated. X-ray microanalysis of the precipitates revealed sodium and calcium, although following cryofixation calcium was not detectable in the vacuoles by X-ray analysis.
通过对果蝇幼虫马氏管近端节段中间细胞区域进行冷冻固定、冷冻切片和冷冻干燥后，利用电子探针X射线微量分析技术，我们研究了电子密度低的液泡的成分。根据此方法，这些液泡以5:1的高相关性（r = 0.98）储存钠和镁。磷、钾和硫也被储存。在液泡周围的中间基质中，元素含量与液泡中的不同。液泡储存钠和镁对离子代谢的意义尚不清楚。除了钠、镁、磷、钾和硫外，液泡还含有3-羟基犬尿氨酸和其他荧光色素。利用焦锑酸盐技术证实了液泡内有沉淀。对沉淀进行X射线微量分析发现了钠和钙，尽管在冷冻固定后通过X射线分析在液泡中未检测到钙。
