In vitro-evaluation of lipid emulsions as vehicles for the administration of xenon: interaction with NMDA receptors.

The noble gas xenon is an antagonist of the NMDA (N-methyl-D-aspartate)-type glutamate receptor which may account for the ideal anesthetic profile and potent neuroprotective properties demonstrated even at subanesthetic concentrations. Because lipid emulsions also promote NMDA antagonistic effects they may serve as ideal carriers for xenon. In this in vitro study, we investigated the efficacy of xenon dissolved in various lipid emulsions (Intralipid, Lipofundin, ClinOleic and Abbolipid on NMDA-evoked currents in cultured cortical neurons. The NMDA receptor blocking property at a clinically relevant concentration seen in the lipid emulsions tested may contribute to the anesthetic, analgetic and neuroprotective effects of xenon administered by way of these lipid carriers. Abbolipid? may serve as the most acceptable carrier since the NMDA antagonistic effect of xenon was enhanced in combination with this emulsion.