Anxiety-like behaviour is attenuated by gabapentin, morphine and diazepam in a rodent model of HIV anti-retroviral-associated neuropathic pain

Neurosci Lett. 2008 Dec 19;448(1):153-6. doi: 10.1016/j.neulet.2008.10.005. Epub 2008 Oct 7.


Neuropathic pain is commonly associated with affective disorders such as anxiety and depression. We have previously characterised a rodent model of HIV, anti-retroviral-associated neuropathy in which rats develop hypersensitivity to a punctate mechanical stimulus and display anxiety-like behaviour in the open field paradigm. To assess the potential of this behavioural paradigm for the assessment of pain related co-morbidities in rodent models of pain, here we test the sensitivity of this anxiety-like behaviour to the analgesic agents gabapentin and morphine in comparison to the known anxiolytic drug diazepam. We found that gabapentin (30 mg/kg, i.p.) and morphine (2.5 mg/kg, i.p.), which reduce mechanical hypersensitivity in these rats, significantly reduces measures of thigmotaxis in the open field. The effect of gabapentin and morphine did not differ significantly from diazepam (1 mg/kg, i.p.). This study highlights the potential use of this rodent model and behavioural paradigm in the validation of the affective component of novel analgesic pharmacological targets and elucidation of underlying pathophysiological mechanisms.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amines / therapeutic use
  • Analgesics / therapeutic use*
  • Animal Diseases
  • Animals
  • Anxiety* / drug therapy
  • Anxiety* / virology
  • Behavior, Animal / drug effects
  • Cyclohexanecarboxylic Acids / therapeutic use
  • Diazepam / therapeutic use
  • Exploratory Behavior / drug effects
  • Gabapentin
  • HIV Infections / complications*
  • Locomotion / drug effects
  • Male
  • Morphine / therapeutic use
  • Neuralgia* / complications
  • Neuralgia* / etiology
  • Neuralgia* / virology
  • Pain Measurement
  • Pain Threshold / drug effects
  • Rats
  • Rats, Wistar
  • Reaction Time / drug effects
  • Time Factors
  • gamma-Aminobutyric Acid / therapeutic use


  • Amines
  • Analgesics
  • Cyclohexanecarboxylic Acids
  • gamma-Aminobutyric Acid
  • Gabapentin
  • Morphine
  • Diazepam