Relationship between gamma-hydroxybutyric acid receptors and the hypnotic and analgesic effects of isoflurane and enflurane

Aim To investigate the relationship between gamma-hydroxybutyric acid receptors(GHBAR)with the hypnotic and analgesic effects of isoflurane and enflurane.Methods Establishing the mice model of hypnosis and analgesia by intraperitoneally injection(ip)and subcutaneously(sc)of appropriate doses of inhalation anesthetics,the different doses of NCS-382 were injected intracerebroventricularly(icv)or intrathecally(it)and then their effects were observed on the sleeping time(ST),the pain index in hot-plate test(HPPI)and writhing times by using acetic acid-induced writhing test.Results In awaken test,NCS-382 1,5,25 μg(icv)could significantly decrease ST of the mice treated with isoflurane and enflurane(P0.01);in hot-plate test,NCS-382 1,5,25 μg(it)did not affect the HPPI in conscious and treated with isoflurane and enflurane mice(P0.05).In acetic acid-induced writhing test,writhing times inhibition induced by sc administered isoflurane and enflurane was not affected by the NCS-382 1,5,25 μg(P0.05).Conclusion NCS-382 may be one of the important targets for the hypnotic effects on thermal-induced nociception,but not analgesic and chemical-induced nociception of isoflurane and enflurane.