GABA agonist induced analgesia elicited from the lateral preoptic area in the rat.

Unilateral microinjections of the GABA agonists muscimol and baclofen into the lateral preoptic area (LPOA) of the rat brain resulted in a significant increase in the latency to respond to a hotplate stimulus on the side contralateral to the injection. Muscimol injected 1.5 mm dorsal to the LPOA site was significantly less effective in changing the hotplate reaction time. The LPOA therefore represents a site from which GABA receptor-mediated analgesia can be elicited.