Tabakoff B, Hoffman P L, Lee J M, Saito T, Willard B, De Leon-Jones F
National Institute on Alcohol Abuse and Alcoholism, Bethesda, Md 20892.
N Engl J Med. 1988 Jan 21;318(3):134-9. doi: 10.1056/NEJM198801213180302.
Blood platelets are an accessible tissue that reflects the activity of many enzymes found in the brain. To investigate the possible effect on such enzymes of long-term consumption of large quantities of ethanol, we assayed the activities of two enzymes, monoamine oxidase and adenylate cyclase, in platelet membranes of men with alcoholism and controls matched for sex and age. We also compared these two groups in terms of the inhibition of platelet monoamine oxidase activity by ethanol in vitro (400 mM), and in terms of the stimulation of adenylate cyclase activity by various agents. There was no significant difference in monoamine oxidase activity between the alcoholics and the controls. However, the inhibition of monoamine oxidase by ethanol was significantly higher in the platelets of alcoholics. The basal activity of adenylate cyclase was the same in platelets from the alcoholics and the controls, but the platelet adenylate cyclase activity after stimulation with guanine nucleotide, cesium fluoride, or prostaglandin E1 was significantly lower in alcoholics. These differences were not associated with age, race, smoking, or illicit drug use, and there was no significant correlation with the duration of problems with alcohol. The changes were long-lasting; cesium fluoride-stimulated adenylate cyclase activity was lower in alcoholic subjects who had abstained from alcohol for one to four years. Discriminant analysis showed that the use of values for the inhibition of monoamine oxidase activity by ethanol and cesium fluoride-stimulated adenylate cyclase activity correctly classified 75 percent of the alcoholics and 73 percent of the controls. These measures may be of value either as indexes of excessive alcohol consumption or as an indication of a predisposition to alcoholism.
血小板是一种可获取的组织，它能反映大脑中多种酶的活性。为了研究长期大量饮用乙醇对这些酶可能产生的影响，我们测定了酗酒男性和年龄、性别匹配的对照组血小板膜中两种酶——单胺氧化酶和腺苷酸环化酶的活性。我们还比较了这两组在体外（400 mM）乙醇对血小板单胺氧化酶活性的抑制作用，以及各种试剂对腺苷酸环化酶活性的刺激作用方面的差异。酗酒者和对照组的单胺氧化酶活性没有显著差异。然而，乙醇对酗酒者血小板中单核细胞氧化酶的抑制作用明显更高。酗酒者和对照组血小板中腺苷酸环化酶的基础活性相同，但在鸟嘌呤核苷酸、氟化铯或前列腺素E1刺激后，酗酒者血小板中的腺苷酸环化酶活性明显更低。这些差异与年龄、种族、吸烟或非法药物使用无关，且与酗酒问题的持续时间没有显著相关性。这些变化是持久的；在戒酒1至4年的酗酒者中，氟化铯刺激的腺苷酸环化酶活性较低。判别分析表明，使用乙醇对单胺氧化酶活性的抑制值和氟化铯刺激的腺苷酸环化酶活性值能正确区分75%的酗酒者和73%的对照组。这些指标可能作为过量饮酒的指标或酗酒易感性的指标具有价值。
