[The study of protoporphyrin IX metabolism in cell proliferation using yolk as the target samples]

In order to find the better target sample to investigate protoporphyrin IX metabolism in the cell proliferation process in chick embryos, the emission spectra of egg white, yolk and urine from non-incubated and incubated eggs were measured under the excitation at 405 nm. It was observed that, among the three components investigated, only yolk sample was possible to get in pureness almost through the whole incubation process. Furthermore, compared with the egg white, the yolk had more obvious characteristic emission of protoporphyrin IX and lower background spectra and turned to be the better target sample for the investigation. The relative characteristic emission intensity of PpIX of yolk samples was used to determine the level of PpIX metabolism. It was found that the relative emission intensity increases during the first 10 days of proliferation process, indicating an increase in the concentration or in the metabolism level of protoporphyrin IX. The relative emission intensity, hence the PpIX metabolism level, then decreased gradually during the rest days of proliferation process. These results are similar to those obtained on human malignant tumors as they develop. The result testifies the point of view further that the abnormity of PpIX metabolism is correlative to the rapid limitless cell proliferation.