Vinpocetine increases the neuroprotective effect of adenosine in vitro

Cultured neurons from chick embryo cerebral hemispheres were used to study the neuroprotective activity of vinpocetine and adenosine against hypoxic damage. Cytotoxic hypoxia was induced by adding 1 mM sodium cyanide to the nutrient medium for 30 min. The drugs were present in the nutrient medium 30 min before, and up to 1 day after hypoxia. To characterize the neuroprotective drug effects, the protein content per culture flask and the neuronal viability were determined 3 days after this hypoxic period. Adenosine, but not vinpocetine, was able to protect neurons against hypoxic damage, when added as single drug to the cultures. However, vinpocetine significantly enhanced the neuroprotective effect of adenosine. The results suggest that the neuroprotective effect of vinpocetine is mediated by adenosine.