Résumé
To demonstrate the possibility of radiotherapy for echinococcosis of rats and to explore its mechanism of action, the effects of different doses of 6 MV X-ray radiotherapy on the activity of Echinococcus granulosus in rats were investigated. After being irradiated by 10, 20, 30 and 40Gy of 6 MV X-ray, a lot of examinations were carried out, such as examination of the ultrastructure of the Echinococcus granulosus cysts in rat with electron microscope, the total amount of proteins and Ca2+ ion in hydatid cyst fluid(HCF) .The potassium-pyroantimonate(PPA) cytochemical method was used to demonstrate whether the blocked calcium channels would be one reason for radiotherapy on Echinococcus granulosus cysts in rat. It was found that the ultrastructures of E.granulosus cysts showed different extents of alterations or damages with abnormal changes and destruction in tissues or cells of cysts. The total protein amount in HCF was increased, while Ca2+ ions in HCF were reduced obviously in the treated groups of rats , especially in high dose groups. With PPA, some electron-dense precipitates were observed on the mitochondria and endocytoplasmic reticulum in the treated groups. It is evident that the structure of cysts of Echinococcus granulosus in rat can be damaged by radiotherapy with certain extent of the quantity-efficiency relationship.
Résumé
Objective To delineate the epidermal calcium ions distribution in normal and acetone-treated nude mouse skin. Methods acetone was applied on the nude mouse skin for 20*!min with cotton balls. The ion capture cytochemistry, i.e., the potassium oxalate-pyroantimonate method was employed to localize calcium ions in nude mouse epidermis for ultrastructural examination. Results Ultrastructural examinations demonstrate that abundant calcium ions displayed within the epidermis, with a low content of calcium in the basal and spinous layers, followed by a progressive increase with calcium content and reaching its maximal density within the outer stratum granulosum. Whereas, application of acetone to the nude mouse skin caused the loss of the epidermal calcium gradient.Conclusion The present results suggest that a calcium gradient exists within normal murine epidermis. Moreover, the ion capture cytochemistry is a potentially powerful investigative tool for the demonstration of epidermal ionic environment.