Alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors participate in the analgesic but not hypnotic effects of emulsified halogenated anaesthetics.
The present study was designed to investigate the role of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors in hypnosis and analgesia induced by emulsified inhalation anaesthetics. After having established the mice model of hypnosis and analgesia by intraperitoneally injecting appropriate doses of emulsified enflurane, isoflurane or sevoflurane, we intracerebroventricularly or intrathecally injected different doses of AMPA and then observed the effects on the sleep time using hypnosis test and the tail-withdrawal latency using the tail-withdrawal test. In hypnosis test, AMPA (50, 75 and 100 ng, intracerebroventricularly) had no distinctive effects on the sleep time of the mice treated with emulsified inhalation anaesthetics (P > 0.05). In tail-withdrawal test, AMPA (0.25, 0.5 and 1.0 ng, intrathecally) significantly and dose-dependently decreased the tail-withdrawal latency (P < 0.05 or P < 0.01) in the mice treated with emulsified anaesthetics. These results suggest that AMPA receptors may participate in the analgesic but not in the hypnotic effects induced by emulsified enflurane, isoflurane or sevoflurane.
Hang
Lihua
L
Department of Anesthesiology, the Affiliated People's Hospital of Jiangsu University and the First People's Hospital of Zhenjiang, Zhenjiang, China.
Shao
Donghua
D
Yang
Yinghong
Y
Sun
Wenjin
W
Dai
Tijun
T
Zeng
Yinming
Y
D000700:Analgesics / Q000494:pharmacology*; D018685:Anesthetics, Inhalation / Q000494:pharmacology*; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004655:Emulsions; D004737:Enflurane / Q000494:pharmacology*; D005260:Female; D006991:Hypnosis, Anesthetic; D007274:Injections, Intraperitoneal; D007276:Injections, Intraventricular; D007278:Injections, Spinal; D007530:Isoflurane / Q000494:pharmacology*; D008297:Male; D008738:Methyl Ethers / Q000494:pharmacology*; D051379:Mice; D010147:Pain Measurement; D017288:Pain Threshold / Q000187:drug effects; D018091:Receptors, AMPA / Q000819:agonists / Q000502:physiology*; D000077149:Sevoflurane; D013997:Time Factors; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid / Q000008:administration & dosage / Q000494:pharmacology
D000700:Analgesics; D018685:Anesthetics, Inhalation; D004655:Emulsions; D008738:Methyl Ethers; D018091:Receptors, AMPA; D000077149:Sevoflurane; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid; D004737:Enflurane; D007530:Isoflurane