ABSTRACT
OBJECTIVE: α-Conotoxin LtIA (α-CTX LtIA, LtIA) is a specific inhibitor of α3β2 nicotinic acetylcholine receptors (nAChRs) from Conus litteratus, a marine snail native to Hainan. The aim of this study was to evaluate the analgesic activity of α-CTX LtIA. METHODS: The analgesic effect of α-CTX LtIA on pain models was evaluated using mice hot-plate and tail-flick models by intracerebroventricular (icv) injection. RESULTS: In tail-flick test, the maximum analgesia percentage (PMAP) was 37.74% at 15 min after LtIA administration by icv injection with dose of 0.2 nmol per mouse. While in hot-plate test, PMAP was 48. 81% at 60 min after LtIA administration by icv injection with same dose of 0.2 nmol per mouse. α-CTX LtIA showed good analgesic activity in two pain models. CONCLUSION: α-CTX LtIA exhibits good analgesic activity by specific interaction with α3β2 nAChRs subtype. These results have great significance for the research and development of LtIA painkiller in the future.