Breath acetaldehyde: evidence of acetaldehyde production by oropharynx microflora and by lung microsomes.
Breath acetaldehyde: evidence of acetaldehyde production by oropharynx microflora and by lung microsomes.
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呼吸乙醛：口咽微生物区系和肺微粒体产生乙醛的证据。
DOI：
10.1007/978-1-4757-1419-7_47
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发表时间：
1980
影响因子：
--
通讯作者：
Lieber,CS
中科院分区：
文献类型：
--
作者：
Pikkarainen,P;Baraona,E;Seitz,H;Lieber,CS
摄入酒精后，在呼出的空气中发现乙醛，并认为其来源于血液。然而，我们发现，在死腔中乙醛与乙醇的比例高于肺泡（呼气末）空气。这一观察结果表明在气道中产生乙醛。为了研究这一点，我们用10 ml生理盐水或5 mM乙醇清洗正常受试者的口腔。用乙醇洗涤每分钟产生5.1 ±1.3 nmol/ml的乙醛（而用盐水洗涤则无）。盐水漱口液与乙醇孵育产生乙醛。这种反应可以通过煮沸或通过洗涤液的微过滤来防止，这表明这是由于口咽部的微生物酶。我们还研究了肺部产生乙醛的可能性。大鼠肺切片产生1.32 ±0.19 mnol乙醛/g肺（湿重）/分钟;也检测到乙醛的微粒体产生，并且这通过慢性乙醇喂养而增强。呼出空气中的乙醇通常用作血液乙醇浓度的指示剂。乙醛--乙醇氧化的产物--也存在于呼出的空气中。呼吸乙醛被认为反映了血液乙醛（Freund和O 'Hollaren，1965;福井，1969），并且它也被用于监测血液浓度的变化（Zeiner等人，1979年）。然而，在气道中可能存在乙醛的局部产生。当乙醇存在于血液中时，它会持续地从唾液中排出。此外，一些细菌和所有酵母（它们是口腔和气道的常见居民）可以通过醇脱氢酶或通过醇氧化酶系统将乙醇氧化成乙醛（Davis等人，1973年）。此外，尽管肺不含显著的乙醇脱氢酶活性，但尚未评估微粒体乙醇氧化产生的乙醛，特别是在慢性饮酒后。这项研究的目的是确定呼气中的乙醛是否完全来自血液，或者是否有其他来源。
After alcohol ingestion, acetaldehyde is found in expired air and is thought to originate from blood. However, we found that the ratio of acetaldehyde to ethanol was higher in dead space than in alveolar (end-expiratory) air. This observation suggested production of acetaldehyde in the airways. To study this, we washed the mouth of normal subjects with 10 ml of either saline or 5 mM ethanol. Washings with ethanol produced 5.1 ±1.3 nmol/ml of acetaldehyde per minute (vs none with saline). Saline mouth washings incubated with ethanol produced acetaldehyde. This reaction could be prevented by boiling or by microfiltration of the washings suggesting that it was due to microbial enzymes of the oropharynx. We also studied the possibility of pulmonary production of acetaldehyde. Rat lung slices produced 1.32 ±0.19 mnol of acetaldehyde/g lung (wet weight)/minute; microsomal production of acetaldehyde was also detected and this was enhanced by chronic ethanol feeding.Ethanol in expired air is commonly used as an indicator of blood ethanol concentration. Acetaldehyde--a product of ethanol oxidation--is also found in expired air. Breath acetaldehyde has been assumed to reflect blood acetaldehyde (Freund and O’Hollaren, 1965; Fukui, 1969) and it has also been used to monitor changes in blood concentrations (Zeiner et al., 1979). However, it is possible that there is a local production of acetaldehyde in the airways. Ethanol is continuously excreted in saliva when present in blood. Moreover, some bacteria and all yeasts, which are common inhabitants of the mouth and airways could oxidize ethanol to acetaldehyde by alcohol dehydrogenase or by alcohol oxidase systems (Davis et al., 1973). Moreover, though lung does not contain significant alcohol dehydrogenase activity, generation of acetaldehyde by microsomal ethanol oxidation, particularly after chronic alcohol consumption, has not been assessed. This study was conducted to determine whether breath acetaldehyde is derived exclusively from the blood or whether there are alternative sources.