Bolmer S D, Kleinerman J
Am J Pathol. 1987 Feb;126(2):209-19.
Administration of D-galactosamine (GalNH2) is known to produce alterations in plasma glycoprotein levels, including alpha 1-antitrypsin. The authors have studied the effects of GalNH2 on circulating protein bound carbohydrates and on the plasma concentrations of two alpha 1-antiproteases, transferrin, IgG, and albumin in rats. The alpha 1-antiproteases from GalNH2-treated rats were isolated and their molecular weight, isoelectric point, and carbohydrate composition compared with those of control rat alpha 1-antiproteases. Total plasma protein, albumin, and transferrin levels in the GalNH2-treated rats do not differ significantly from those of control rats. Plasma protein-bound carbohydrate is decreased significantly in the experimental animals, compared with controls: sialic acid decreased 60%, neutral sugars decreased 43%, and amino sugars decreased 38%. The concentrations of alpha 1-antitrypsin (AAT) and a higher molecular weight alpha 1-antiprotease designated AP2 are decreased by 79% and 38%, respectively. AAT isolated from the plasma of GalNH2-treated rats contains 2-3 fewer moles of sialic acid, 3 fewer moles of neutral sugar, and 2 fewer moles of amino sugar per mole of antiprotease than AAT isolated from controls. AP2 from GalNH2-treated rats contains 1 fewer mole each of sialic acid, neutral sugar, and amino sugar per mole of antiprotease than AP2 from controls. These alterations are similar to those seen in humans with genetically determined alpha 1-antiprotease deficiency.
已知给予D-半乳糖胺（GalNH2）会导致血浆糖蛋白水平发生变化，包括α1-抗胰蛋白酶。作者研究了GalNH2对大鼠循环中蛋白质结合碳水化合物以及两种α1-抗蛋白酶、转铁蛋白、IgG和白蛋白血浆浓度的影响。分离出GalNH2处理大鼠的α1-抗蛋白酶，并将其分子量、等电点和碳水化合物组成与对照大鼠的α1-抗蛋白酶进行比较。GalNH2处理大鼠的总血浆蛋白、白蛋白和转铁蛋白水平与对照大鼠相比无显著差异。与对照组相比，实验动物血浆中蛋白质结合的碳水化合物显著减少：唾液酸减少60%，中性糖减少43%，氨基糖减少38%。α1-抗胰蛋白酶（AAT）和一种分子量较高的α1-抗蛋白酶AP2的浓度分别降低了79%和38%。从GalNH2处理大鼠血浆中分离出的AAT，每摩尔抗蛋白酶所含的唾液酸摩尔数比从对照中分离出的AAT少2 - 3摩尔，中性糖少3摩尔，氨基糖少2摩尔。GalNH2处理大鼠的AP2每摩尔抗蛋白酶所含的唾液酸、中性糖和氨基糖摩尔数均比对照的AP2少1摩尔。这些变化与遗传性α1-抗蛋白酶缺乏的人类患者所见相似。
