Releasable, non-neuronal GABA pool in rat stomach.

The uptake and K+-evoked release of [3H] gamma-aminobutyric acid (GABA) was examined in tissue slices from rat gastric antrum. Active [3H]GABA accumulation was observed that could only be partially inhibited by L-diaminobutyric acid (L-DABA), a blocker of neuronal GABA uptake. The L-DABA-insensitive uptake component was saturable, sodium-dependent and of high affinity. Moreover, [3H]GABA could be released from this L-DABA-resistant pool by a high K+ concentration. It is concluded that a releasable, non-neuronal GABA pool, which may have some functional significance, is present in the gastric antrum.