摘要
用~3H标记胆固醇和放射自显影技术,研究了水稻(Oryza Sativa L.)幼苗对外源胆固醇的吸收、运转和分布。结果表明,外源胆固醇能迅速地被根系吸收和转运,并且在3天试验时间内地上部叶片和膜脂中放射性强度的积累几乎呈直线增加,而各叶分配量依次为第2叶】第3叶】第4叶;涂叶试验证明,除涂叶本身大量积累~3H-胆固醇外,各部位依次为第1叶】根】第3叶】第4叶;从放射自显影照片上看出,银粒定位在液泡和原生质中以及质膜和其他亚细胞器。结果证明,水稻根和叶不仅能迅速地吸收外源胆固醇,而且能够进行根—叶之间和叶—叶之间转移,最终在细胞内与膜系结合以影响膜的结构和功能。
The absorption, transportation and distribution of exogenous cholesterol in rice(Oryza sativa L.)seednngs were studied by means of ~3H-labelled autoradiographic technique. The results showed that exogenous cholesterol was soon absorbed and transported by the root system, the accumulated radioactivity of the aerial leavesand membrane lipid almost sharply increased during the three-day experimentul period with the distribution among the leaves in the order of the second leaf>the third leaf>the fourth leaf. Test of spreading the second leaves with ~3H-cholesterol proved that a- side from a large amount of radioactivity accumulation in the spread leaves themselves, ~3H-choles- terol was also distributed in other parts in the order of the first leaf>root>the third leaf>the fourth leaf. Radioautography showed that the silver grains were localized at vacuole and proto- plasm as well as plasma membrane and other sub-cell organs. The above results indicate that rice root system and leaves not only absorb exogenous cholesterol quickly but also transport it between roots and leaves and between leaves,where it finally combines with the membrane system in cell to affect the structure and function of the membrane.
基金
国家自然科学基金
关键词
水稻
幼苗
胆固醇
吸收
Rice seedling
~3H-cholesterol
