Acetaldehyde adducts with haemoglobin: determination of acetaldehyde released from haemoglobin by acid hydrolysis

Acetaldehyde, the first metabolite of ethanol, reacts with haemoglobin in vitro to produce acetaldehyde-haemoglobin adducts. Some clinical studies on the minor haemoglobins have suggested that these adducts may be formed in people abusing alcohol. Under hydrolysis of haemoglobin, with oxalic acid at 100 degrees C in sealed vials, some acetaldehyde was released and then specifically determined by HPLC. The kinetics of hydrolysis were studied using haemoglobin previously labelled with 14[C] acetaldehyde. The maximum liberation of 14 [C] acetaldehyde was obtained after 3 hr 30 min hydrolysis and this time factor was then utilized in the analysis of alcoholic and control haemoglobin. Thus, we have confirmed the formation of acetaldehyde haemoglobin adducts in vivo. It must be noted that the released acetaldehyde corresponds only to an index of the stable adducts. The levels were higher in alcoholics than in controls (1.417 +/- 0.171 and 1.295 +/- 0.139 nmol/mg Hb, respectively, P less than 0.001). In conclusion, this marker is not a convenient tool for the monitoring of alcohol exposure levels because of the low differences between alcoholic and control haemoglobins.