Mystic acetaldehyde: the never-ending story on alcoholism

After decades of uncertainties and drawbacks, the study on the role and significance of
acetaldehyde in the effects of ethanol seemed to have found its main paths. Accordingly,
the effects of acetaldehyde, after its systemic or central administration and as obtained
following ethanol metabolism, looked as they were extensively characterized. However,
almost 5 years after this research appeared at its highest momentum, the investigations
on this topic have been revitalized on at least three main directions: (1) the role and the
behavioral significance of acetaldehyde in different phases of ethanol self-administration
and in voluntary ethanol consumption; (2) the distinction, in the central effects of
ethanol, between those arising from its non-metabolized fraction and those attributable
to ethanol-derived acetaldehyde; and (3) the role of the acetaldehyde-dopamine
condensation product, salsolinol. The present review article aims at presenting and
discussing prospectively the most recent data accumulated following these three
research pathways on this never-ending story in order to offer the most up-to-date
synoptic critical view on such still unresolved and exciting topic.