Uptake and Calcium‐Dependent Release of Ethylenediamine (1,2‐Diaminoethane) by Rat Brain Slices

: The uptake of [14C]ethylenediamine into slices of rat brain and its subsequent evoked release have been studied. An active uptake process was demonstrated by comparing uptake at 37 and 4°C. This uptake showed aKm of 1.36 mM, was partly sodium‐dependent and was reduced by nipecotic acid. Release could be readily evoked by 30 mM potassium, and by electrical stimulation, the release in both cases being calcium‐dependent. In view of these findings and the reported interactions of ethylenediamine with γ‐aminobutyric acid‐related mechanisms, it might be of interest to determine whether this simple diamine occurs endogenously in the mammalian brain.