Carey E M, Foster P C
Biochim Biophys Acta. 1984 Jan 17;792(1):48-58. doi: 10.1016/0005-2760(84)90281-9.
Phospholipid exchange activity has been determined in the supernatant fraction of rat brain from birth through to maturity by measuring the protein-catalysed transfer of total and individual 32P-labelled phospholipids from microsomal membranes to mitochondria, and the transfer of [14C]phosphatidylcholine from liposomes to mitochondria. Transfer activity has also been compared in brain and liver supernatant. Overall phospholipid exchange activity in the brain increased only slightly with age. The activity at birth was 75% of the adult value. However, the transfer of individual phospholipids showed markedly different trends during postnatal brain development. The transfer of phosphatidylinositol (PI) and ethanolamine phospholipids increased postnatally to a maximum at 9 days of age, with lowest values in adult brain. Phosphatidylcholine (PC) transfer increased from 9 days to reach maximum values in the mature brain. The transfer of sphingomyelin was highest immediately after birth. PI transfer activity was higher in brain than liver, while PC and ethanolamine phospholipid transfer activity was higher in liver. The heterogeneity of phospholipid exchange proteins in central nervous system tissue is reflected in the developmental changes in exchange activity towards individual phospholipids. The various exchange proteins appear to have separate induction mechanisms. The presence of exchange-protein activity from birth in the rat indicates the functional importance of phospholipid transport during cell acquisition and membrane proliferation. Activity is not primarily associated with membrane formation such as the formation of the myelin sheath, and therefore is more likely to be involved in the process of phospholipid turnover.
通过测量蛋白质催化的总磷脂和单个32P标记磷脂从微粒体膜到线粒体的转移，以及[14C]磷脂酰胆碱从脂质体到线粒体的转移，测定了从出生到成熟的大鼠脑上清液部分的磷脂交换活性。还比较了脑和肝上清液中的转移活性。脑中的总体磷脂交换活性仅随年龄略有增加。出生时的活性为成年值的75%。然而，在出生后脑发育过程中，单个磷脂的转移呈现出明显不同的趋势。磷脂酰肌醇（PI）和乙醇胺磷脂的转移在出生后增加，在9日龄时达到最大值，在成年脑中值最低。磷脂酰胆碱（PC）转移从9日龄开始增加，在成熟脑中达到最大值。鞘磷脂的转移在出生后立即最高。PI转移活性在脑中高于肝脏，而PC和乙醇胺磷脂转移活性在肝脏中更高。中枢神经系统组织中磷脂交换蛋白的异质性反映在对单个磷脂的交换活性的发育变化中。各种交换蛋白似乎有不同的诱导机制。大鼠出生时就存在交换蛋白活性，这表明磷脂转运在细胞获取和膜增殖过程中具有功能重要性。活性并非主要与膜形成如髓鞘形成相关，因此更可能参与磷脂周转过程。
