gamma-Aminobutyric acid (GABA) is a transmitter of enteric interneurons, targeting excitatory GABA(A) or inhibitory GABA(B) receptors that modulate motility and mucosal function. Enteric GABA may also subserve hormonal and paracrine signaling. Disruption in gastrointestinal function following perturbation of enteric GABA receptors presents potential new target sites for drug development.