Antinociceptive action of N-octanoyl GABA--a new GABA mimetic agent

A new derivative of gamma-aminobutyric acid (GABA) was synthesized. The compound, N-octanoyl GABA (O-GABA), exhibited positive analgesic response in four different models in mice--tail immersion, hot plate, tail clip and acetic acid induced writhing. The antinociceptive activity was significantly blocked by picrotoxin but not by bicuculline or 3-mercaptopropionic acid. Naloxone failed to reverse the antinociceptive response of O-GABA but a synergistic action was observed with pethidine. Pretreatment with atropine significantly reduced the antinociceptive action of O-GABA. Biochemical tests revealed that O-GABA significantly increased brain GABA levels.