On the Accuracy of In Vivo Ethanol and Acetaldehyde Monitoring, a Key Tile in the Puzzle of Acetaldehyde as a Neuroactive Agent

Over the last 20 years researchers have explored the postulated role of acetaldehyde (ACD) as a mediator of some of the actions of ethanol (EtOH) in the central nervous system (CNS). However, efforts have been hampered mainly by the difficulty of directly measuringin vivoEtOH and ACD levels in the CNS and thus, our knowledge is based on indirect evidences. Although technically challenging, the development of reliable methods forin vivomeasurement of ACD and EtOH is of paramount importance to solve the “puzzle of acetaldehyde as a neuroactive agent.” In this short review we discuss the recent advances on brain EtOH pharmacokinetic and state-of-the-art available techniques that could be used forin vivodetect EtOH and ACD both non-invasively (magnetic resonance spectroscopy), and invasively (microdialysis and biosensors). Among the differentin vivosampling techniques described, particular emphasis is paid to the field of enzyme-based amperometric biosensors. Biosensors have gained much attention in recent years for their ability to online monitor biological signalsin vivo, and several micro- and nano-structured devices have been successfully used forin vivostudies. Owing to their high temporal and spatial resolution, biosensors could provide the adequate technology for studyingin vivoEtOH pharmacokinetic.