, Volume 168, Issue 4, pp 446–454 | Cite as

Anxiolytic effects of a novel group II metabotropic glutamate receptor agonist (LY354740) in the fear-potentiated startle paradigm in humans

  • Christian Grillon
  • Jeremy Cordova
  • Louise R. Levine
  • Charles A. Morgan, III
Original Investigation



LY354740, a structural analogue of glutamate that shows specificity at the mGluR2/3 receptor, has anxiolytic effects in animal models.


This study investigated the anxiolytic effects of LY354740 in humans using the fear-potentiated startle reflex methodology.


Subjects were given either placebo (n=16), 20 mg LY354740 (n=15), or 200 mg LY354740 (n=13). The fear-potentiated startle tests examined startle potentiation to shock anticipation and to darkness.


Consistent with previous results, startle was increased by threat of shock and by darkness. LY354740 did not affect baseline startle. Correspondingly, subjects did not report LY354740 to be sedative. LY354740 significantly reduced the increase in startle magnitude during shock anticipation, but not during darkness. Subjective reports of state anxiety and negative affectivity during the fear-potentiated startle tests were also reduced in a dose-dependent manner by LY354740.


These results suggest that LY354740 has an anxiolytic profile in humans without being sedative.


Glutamate LY354740 Fear Anxiolytic Fear-potentiated startle Darkness 



The authors acknowledge Lilly Research Laboratories for their financial assistance and for providing LY354740. The work was conducted at Yale University School of Medicine, Department of Psychiatry, New Haven, Conn., USA.


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Copyright information

© Springer-Verlag 2003

Authors and Affiliations

  • Christian Grillon
    • 1
  • Jeremy Cordova
    • 2
  • Louise R. Levine
    • 3
  • Charles A. Morgan, III
    • 2
  1. 1.NIMH/NIH/DHHSMood and Anxiety Disorder ProgramBethesdaUSA
  2. 2.Connecticut VA Medical CenterWest HavenUSA
  3. 3.Lilly Research LaboratoriesLilly Corporate Center, Eli Lilly and CompanyIndianapolisUSA

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