Gross M D, Hays R, Gapstur S M, Chaussee M, Potter J D
Division of Epidemiology, School of Public Health, University of Minnesota, Minneapolis 55454-1015.
Alcohol Alcohol. 1994 Jan;29(1):31-41.
Acetaldehyde readily reacted with red blood cells and isolated haemoglobin to form adducts. We examined acetaldehyde-haemoglobin reaction products, isolated from red blood cells incubated with acetaldehyde (AcH), for the presence of stable peptide-specific acetaldehyde adducts. Red blood cell incubations were with 20, 50, and 200 mM acetaldehyde for 3, 24 and 48 hr. Peptide-specific [14C]acetaldehyde modifications of Hb from each incubation were identified by tryptic peptide mapping procedures. Nine peptides had modifications and six were found in incubations with 20 mM acetaldehyde. Two of the peptides were acetaldehyde modifications of the Hb alpha- and beta-chain N-termini. Stability studies indicated that the remaining seven [14C]AcH-modified peptides did not result, as can occur under certain conditions, from the transfer of AcH on the N-termini of Hb to N-termini formed after trypsin digestion. An analysis of the relative amounts of [14C]AcH-peptide adducts indicated that at least two of the seven peptides had reactivities for AcH different than the N-termini of Hb; that is, at least two modified peptides differ from imidazolidine-type adducts formed on the N-termini. The presence of multiple modifications with different sensitivities for AcH adduct formation may be useful in developing markers of alcohol consumption.
乙醛很容易与红细胞和分离出的血红蛋白发生反应形成加合物。我们检测了从与乙醛（AcH）孵育的红细胞中分离出的乙醛 - 血红蛋白反应产物，以确定是否存在稳定的肽特异性乙醛加合物。红细胞分别与20、50和200 mM乙醛孵育3、24和48小时。通过胰蛋白酶肽图谱分析程序鉴定了每次孵育中血红蛋白的肽特异性[14C]乙醛修饰。有9种肽发生了修饰，其中6种在与20 mM乙醛的孵育中被发现。其中两种肽是血红蛋白α链和β链N端的乙醛修饰。稳定性研究表明，其余7种[14C]AcH修饰的肽并非如在某些条件下可能发生的那样，由血红蛋白N端的AcH转移到胰蛋白酶消化后形成的N端所致。对[14C]AcH - 肽加合物相对量的分析表明，这7种肽中至少有两种对AcH的反应性与血红蛋白的N端不同；也就是说，至少有两种修饰肽不同于在N端形成的咪唑烷型加合物。存在对AcH加合物形成具有不同敏感性的多种修饰，可能有助于开发酒精消费标志物。
