Regulation of sterol absorption in intestine

本文研究了植物甾醇在SHRSP大鼠体内的沉积和吸收，其中油菜籽甾醇、油菜籽甾醇、谷甾醇、豆甾醇和谷甾醇在SHRSP大鼠体内沉积。在所研究的植物甾醇中，油菜籽甾醇的沉积和吸收最高。谷甾醇的含量也较高。肝脏中植物甾醇含量与吸收率呈高度正相关。结果提示，SHRSP大鼠体内植物甾醇的沉积依赖于其吸收速率。比较SHRSP大鼠与WKA、WKY和Wistar大鼠ABCG5和ABCG8的基因序列。未发现ABCG8基因突变。在ABCG5中发现了一个突变，但这一点必须得到证实。ABCG5和ABCG8在不同品系大鼠肠道中的表达差异无统计学意义。体内植物甾醇沉积越多，肝脏中ABCG5和ABCG8的表达越低。结果提示，ABCG5和ABCG8可能参与了植物甾醇从肝脏向胆汁的排泄。

Deposition and absorption of various plant sterols, campesterol, brassicasterol, sitosterol, stigmasterol and sitostanol, were investigated in SHRSP rats, which was shown to deposit plant sterols in their body. Deposition and absorption of campesterol were highest among plant sterols examined. Those of sitosterol were also higher. Highly positive correlation was observed between plant sterol content in the liver and the absorption rate. The results suggest that deposition of plant sterols in SHRSP rats depends on their absorption rate. cDNA sequences of ABCG5 and ABCG8 in SHRSP rats were compared with those of WKA, WKY and Wistar rats. No mutation was found in ABCG8. One mutation was found in ABCG5, but this must be confirmed. There was no-difference in expression of ABCG5 and ABCG8 in the intestine among the rat strains examined. Higher the deposition of plant sterols in the body, lower the expression of ABCG5 and ABCG8 in the liver. The results suggest that ABCG5 and ABCG8 might participate in excretion of plant sterols from liver to bile.