Maturation of macroreticulocyte membranes in vivo.
Maturation of macroreticulocyte membranes in vivo.
复制标题
大网织红细胞膜在体内的成熟。
DOI：
10.5555/uri:pii:0022214372900832
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发表时间：
1972
期刊：
影响因子：
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通讯作者：
R. A. Cooper
中科院分区：
文献类型：
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作者：
S. Shattil;S. Shattil;R. A. Cooper;R. A. Cooper
摘要采用两种动物模型，在11 d内研究了巨网织红细胞膜的成熟过程。(1)大鼠急性失血引起网状细胞增多症，辐照使其停止；(2)换血后红细胞增多大鼠出现网状细胞缺乏症。网状细胞从46.1%（受辐射大鼠）和30.7%（交换大鼠）下降到第五天的正常水平。网织红细胞平均体积下降29%（从108 μ 3降至77 μ 3，正常=63 μ 3），红细胞平均血红蛋白含量下降26%（从29.7降至21.9 μg，正常=20.8 μg）。富含网状红细胞的血液中51cr的一半存活率降低了1.5至1.9天，但在校正成熟过程中每个细胞血红蛋白（和51cr）的损失后，细胞存活率正常。年轻网织红细胞（平均循环年龄=0.25天）的胆固醇含量是成熟红细胞的2.5倍，磷脂含量是成熟红细胞的4倍。在成熟过程中，它们损失了44%的胆固醇和67%的磷脂。网织红细胞离体细胞膜的胆固醇：磷脂摩尔比（C:P）与成熟细胞相当。这些膜占年轻网织红细胞磷脂的50%和胆固醇的80%以上。大约有13个脂质在成熟过程中丢失。线粒体部分胆固醇含量较低。在网状细胞成熟的前2天，它似乎大部分消失，到第5天完全消失。脾切除术降低了网状红细胞成熟过程中脂质损失的速度和程度，导致成熟红细胞富含脂质。尽管如此，脾切除动物的质膜脂损失是脾脏完整动物的75%。这些研究表明，在成熟过程中，巨网织红细胞损失了大量的脂质。这主要是由于富含磷脂的胞内细胞器，主要是线粒体的损失。然而，在成熟过程中，由于体内因素的作用，巨网织红细胞也会损失大约13%的质膜脂。脾脏是这些因素之一。
Abstract Maturaton of macroreticulocyte membranes was studied over 11 days in 2 animal models in vivo. (1) Reticulocytosis was induced by acute blood loss in rats and halted by irradiation; and (2) reticulocytosis was established in polycythemic rats by exchange transfusion. Reticulocytes fell from 46.1 per cent (in irradiated rats) and 30.7 per cent (in exchanged rats) to normal by day 5. Mean cell volume of reticulocytes decreased 29 per cent (from 108 μ 3 to 77 μ 3 ; normal=63 μ 3 ), and mean cell hemoglobin content decreased 26 per cent (from 29.7 to 21.9 μμg; normal=20.8 μμg). The measured 51 Cr half-survival of reticulocyte-rich blood was decreased 1.5 to 1.9 days, but cell survival was normal when corrected for the loss of hemoglobin (and 51 Cr) per cell during maturation. Young reticulocytes (mean age in the circulation=0.25 days) had a cholesterol content 2.5-fold and phospholipid content 4-fold that of mature red cells. They lost 44 per cent of this cholesterol and 67 per cent of this phospholipid during maturation. Isolated plasma membranes of reticulocytes had a cholesterol:phospholipid molar ratio (C:P) equal to that of mature cells. These membranes accounted for 50 per cent of the phosphoiipid and greater than 80 per cent of the cholesterol of young reticulocytes. Approximately 13 of this lipid was lost during maturation. The mitochondrial fraction was cholesterol-poor. It appeared to be lost largely during the first 2 days of reticulocyte maturation and completely by day 5. Splenectomy decreased the rate and extent of lipid loss during reticulocyte maturation resulting in mature red cells rich in lipid. Nonetheless, the loss of plasma membrane lipid in splenectomized animals was 75 per cent of that occuring in animals with intact spleens. These studies demonstrate that the macroreticulocyte loses substantial amounts of lipid during maturation. Much of this results from the loss of phospholipid-rich intracellular organelles, primarily, mitochondria. However, macroreticulocytes also lose approximately 13 of their plasma membrane lipids during maturation due to factors operative in vivo. The spleen is one of these factors.