Ontogeny of basolateral membrane lipid composition and fluidity in small intestine.
Ontogeny of basolateral membrane lipid composition and fluidity in small intestine.
复制标题
小肠基底外侧膜脂质成分和流动性的个体发育。
DOI：
10.1152/ajpgi.1989.257.1.g138
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发表时间：
1989
期刊：
影响因子：
--
通讯作者：
Medow,MS
中科院分区：
文献类型：
--
作者：
Schwarz,SM;Bostwick,HE;Danziger,MD;Newman,LJ;Medow,MS
为了评估出生后发育过程中小肠基侧细胞表面的物理化学性质，从哺乳期(14-17天)和断奶成熟(35-49天)的兔空肠和回肠细胞分离膜，纯化30-40倍(基于Na+-K+-ATPase比活性)，并限制共分离细胞成分的污染。膜脂分析显示总脂质(每毫克蛋白)随年龄增加而减少，近端至远端增加。出生后空肠膜总胆固醇(哺乳期和成熟期分别为0.18和0.26摩尔/毫克蛋白；P<0.01)和回肠(0.18和0.31摩尔/毫克蛋白；P<0.01)显著增加胆固醇/磷脂摩尔比(空肠，0.43和0.73；回肠，0.43和0.72摩尔/毫克蛋白；P<0.01)。成熟动物的膜上神经鞘氨醇和磷脂酰胆碱相对含量较高，回肠脂肪酰基饱和度高于空肠。用1，6-二苯基-1，3，5-己三烯和DL-12-(9-己基)硬脂酸作为荧光团，提取的膜脂制备的基侧膜和脂质体的流动性在成年兔体内显著降低。Arrhenius图显示成熟膜脂的表观热致转变温度较高。因此，这些数据表明，在断奶期间，小肠基侧膜脂成分和流动性发生了显着变化。讨论了膜蛋白功能与个体发育的可能关系。
To evaluate physicochemical properties of the small intestinal basolateral cell surface during postnatal development, membranes were isolated from suckling (14-17 days) and weanling-mature (35-49 days) rabbit jejunal and ileal enterocytes at 30- to 40-fold purification (based on Na+-K+-ATPase specific activity) and with limited contamination from coisolated cellular elements. Membrane lipid analysis demonstrated age-dependent reductions and proximal to distal increases in total lipid (per milligram protein). Postnatal increases in membrane total cholesterol of jejunum (suckling vs. mature, 0.18 vs. 0.26 mumol/mg protein; P less than 0.01) and ileum (0.18 vs. 0.31 mumol/mg protein; P less than 0.01) resulted in markedly higher cholesterol-to-phospholipid molar ratios (jejunum, 0.43 vs. 0.73; ileum, 0.43 vs. 0.72 mumol/mg protein; P less than 0.01). Membranes from mature animals had higher relative sphingomeylin and phosphatidylcholine content and, in both age groups, fatty acyl saturation was increased in ileum compared with jejunum. By utilization of the fluorophores 1,6-diphenyl-1,3,5-hexatriene and DL-12-(9-anthroyl)stearic acid, the fluidity of basolateral membranes and liposomes prepared from extracted membrane lipid decreased markedly in mature rabbits. Arrhenius plots demonstrated higher apparent thermotropic transition temperatures of mature membrane lipid. These data therefore demonstrate significant changes in small intestinal basolateral membrane lipid composition and fluidity that occur during the weaning period. Possible relationships to ontogenesis of membrane protein function are discussed.