Supraspinal antinociceptive effect of apelin-13 in a mouse visceral pain model.

摘要: Abstract Apelin, as the endogenous ligand of APJ receptor, is a novel identified neuropeptide whose biological functions are not fully understood. receptor mRNA was found in several brain regions related to descending control system pain, such amygdala, hypothalamus and dorsal raphe nucleus (DRN). The present study designed determine whether supraspinal apelin-13 may produce antinociceptive effect observed acetic acid-induced writhing test, model visceral pain. Apelin-13 only significantly produced preemptive antinociception at dose 0.3, 0.5, 1 3 μg/mouse when injected intracerebroventricularly (i.c.v.) before acid, but also induced i.c.v. after acid. And did influence 30-min locomotor activity counts mice. Intrathecal (i.t.) administration (1 3 μg/mouse) decreased number writhes, however, intraperitoneal (i.p.) injection (10–100 μg/mouse) had no on writhes test. specific antagonist apelin-13(F13A), no-specific opioid naloxone μ-opioid β-funaltrexamine hydrochloride (β-FNA) could antagonize apelin-13, suggesting involved this process. Central low (0.3 μg/mouse, i.c.v.) potentiate analgesic potencies modest even relatively ineffective doses morphine administrated level. This enhanced reversed by naloxone, that potentiated response mediated opioid-responsive neurons.