In the present study the ability of tachykinin agonists and antagonists to modulate γ-aminobutyric acid (GABA) release has been correlated with tachykinin receptor expression in the mouse striatum. Significant GABA release was observed when striatal slices were challenged with the NK-3 receptor agonist senktide, the selectivity of which was confirmed using the NK-3 receptor antagonist SR142801. In situ hybridisation revealed co-expression of NK-3 receptors with nitric oxide synthase (NOS)/preprosomatostatin containing GABAergic interneurones. These findings suggest that tachykinins modulate GABA release within the striatum via interaction with NK-3 receptors on somatostatin/NOS interneurones.