Preparation of subcellular membranes from rat intestinal scrapings or isolated cells. Different Ca2+ binding, nonesterified fatty acid levels, and lipolytic activity.
Preparation of subcellular membranes from rat intestinal scrapings or isolated cells. Different Ca2+ binding, nonesterified fatty acid levels, and lipolytic activity.
复制标题
从大鼠肠刮片或分离的细胞中制备亚细胞膜。
DOI：
10.1016/0016-5085(86)90435-x
复制
发表时间：
1986
期刊：
影响因子：
29.4
通讯作者：
Weiser,MM
中科院分区：
文献类型：
--
作者：
Walters,JR;Horvath,PJ;Weiser,MM
从刮取的大鼠小肠粘膜匀浆中制备的基侧、刷缘和富含高尔基体的亚细胞膜部分，含有异常高浓度的非酯化脂肪酸。这些脂肪酸似乎是导致大量钙结合的原因，此前有证据表明，这种作用在维生素D缺乏时会减弱。相比之下，由分离细胞制备的基侧膜和高尔基膜的非酯化脂肪酸和钙结合水平较低。分离的细胞没有经过通常的洗涤程序，发现了中间水平。除了脂肪酶抑制剂磷酸二乙酯的碎屑匀浆外，还可以将钙结合和非酯化脂肪酸降低到与从分离细胞制备的膜中类似的水平。磷脂酶A活性在分离的细胞匀浆中低，在刮片中高；在维生素D缺乏的大鼠的肠刮片中，磷脂酶A的活性降低。回肠膜比十二指肠膜有更多的钙结合，回肠匀浆也有更高的磷脂酶A活性。从大鼠肠道刮片制备亚细胞膜可能会导致脂质组成的改变，这可能是由于脂解酶的活性；除了增加阳离子结合外，这些高水平的脂肪酸还可能影响其他膜特性和酶功能。
Basolateral, brush-border, and Golgi-enriched subcellular membrane fractions, prepared from homogenates of rat small intestinal mucosa obtained by scraping, had unusually high concentrations of nonesterified fatty acids. These fatty acids appear to be responsible for the large amount of calcium binding, an effect that previously was shown to be reduced in vitamin D deficiency. In contrast, basolateral and Golgi membranes prepared from isolated cells had low levels of nonesterified fatty acids and calcium binding. Intermediate levels were found with isolated cells that were not put through the usual washing procedures. Addition to homogenates of scrapings of a lipase inhibitor, diethyl-p-nitrophenyl phosphate, reduced calcium binding and nonesterified fatty acids to levels similar to those in membranes prepared from isolated cells. Phospholipase A activity was low in homogenates of isolated cells and high in scrapings; this was reduced in intestinal scrapings of vitamin D-deficient rats. Ileal membranes had more calcium binding than duodenal membranes, and ileal homogenates also had greater phospholipase A activity. Preparation of subcellular membranes from rat intestinal scrapirigs can result in altered lipid composition, probably due to lipolytic enzyme activity; in addition to increasing cation-binding, these high levels of fatty acids may affect other membrane properties and enzyme function.