The effects of tramadol on electroencephalographic spectral parameters and analgesia in rats.

The effects of different doses of tramadol on analgesia and electroencephalographic (EEG) spectral parameters were compared in rats. Saline or tramadol 5, 10, 20 or 40 mg/kg was administered. The degree of analgesia was evaluated by tail-flick latency, and the degree of seizure was measured using numerical seizure score (NSS). Additionally, band powers, median power frequency and spectral edge frequency 95 were measured to quantify the EEG response. All doses of tramadol produced spike-wave discharge. Tramadol significantly and dose-dependently increased the analgesia, but these effects did not correspond with the changes in the EEG spectral parameters. NSS significantly increased in the Tramadol 20 and 40 mg/kg treatment groups compared to the Control and TRA5 groups, and two rats given 40 mg/kg had convulsions. In conclusion, tramadol dose-dependently increased the analgesic effect, and the 10 mg/kg dose appears to be a reliable clinical dose for analgesia in rats, but dose-dependent increases in analgesia and seizure severity did not correlate with EEG spectral parameters.

[1]  C. Johnson,et al.  Electroencephalographic responses of tramadol, parecoxib and morphine to acute noxious electrical stimulation in anaesthetised dogs. , 2010, Research in veterinary science.

[2]  Maan-Gee Lee,et al.  Atipamezole changes the antinociceptive effects of butorphanol after medetomidine-ketamine anaesthesia in rats. , 2009, Veterinary anaesthesia and analgesia.

[3]  M. Giorgi,et al.  Biopharmaceutical profile of tramadol in the dog , 2009, Veterinary Research Communications.

[4]  B. Rohrbach,et al.  Effects of tramadol on the minimum alveolar concentration of sevoflurane in dogs. , 2009, Veterinary anaesthesia and analgesia.

[5]  Sung Hee Lee,et al.  Evaluation of the anaesthetic effects of medetomidine and ketamine in rats and their reversal with atipamezole. , 2009, Veterinary anaesthesia and analgesia.

[6]  S. Ozkan,et al.  Epileptic seizure during patient-controlled analgesia with tramadol. , 2009, European Journal of Anaesthesiology.

[7]  B. Min,et al.  Spinal cholinergic mechanism of the relieving effects of electroacupuncture on cold and warm allodynia in a rat model of neuropathic pain , 2009, The Journal of Physiological Sciences.

[8]  R. Sansone,et al.  Tramadol: seizures, serotonin syndrome, and coadministered antidepressants. , 2009, Psychiatry (Edgmont (Pa. : Township)).

[9]  C. Johnson,et al.  Glomerular filtration rate after tramadol, parecoxib and pindolol following anaesthesia and analgesia in comparison with morphine in dogs. , 2009, Veterinary anaesthesia and analgesia.

[10]  P. Dowling,et al.  Pharmacokinetics of intravenous tramadol in dogs. , 2008, Canadian journal of veterinary research = Revue canadienne de recherche veterinaire.

[11]  W. Bauer,et al.  Involvement of serotonin 2A receptors in the analgesic effect of tramadol in mono-arthritic rats , 2008, Brain Research.

[12]  M. Britzi,et al.  Pharmacokinetics of tramadol in horses after intravenous, intramuscular and oral administration. , 2007, Journal of veterinary pharmacology and therapeutics.

[13]  B. Pypendop,et al.  Pharmacokinetics of tramadol, and its metabolite O-desmethyl-tramadol, in cats. , 2007, Journal of veterinary pharmacology and therapeutics.

[14]  D. Mellor,et al.  Validation of the acute electroencephalographic responses of calves to noxious stimulus with scoop dehorning , 2007, New Zealand veterinary journal.

[15]  J. Murrell,et al.  Comparative effect of thermal, mechanical, and electrical noxious stimuli on the electroencephalogram of the rat. , 2007, British journal of anaesthesia.

[16]  I. Sora,et al.  Mu opioid receptor-dependent and independent components in effects of tramadol , 2006, Neuropharmacology.

[17]  M. Tescione,et al.  Effect of Tramadol on Bispectral Index during Intravenous Anaesthesia with Propofol and Remifentanil , 2006, Anaesthesia and intensive care.

[18]  H. A. Haga,et al.  Electroencephalographic and cardiovascular variables as nociceptive indicators in isoflurane-anaesthetized horses. , 2005, Veterinary anaesthesia and analgesia.

[19]  H. Na,et al.  Gabapentin relieves mechanical, warm and cold allodynia in a rat model of peripheral neuropathy , 2004, Neuroscience Letters.

[20]  B. Kukanich,et al.  Pharmacokinetics of tramadol and the metabolite O-desmethyltramadol in dogs. , 2004, Journal of veterinary pharmacology and therapeutics.

[21]  F. Jensen,et al.  NBQX or Topiramate Treatment after Perinatal Hypoxia‐induced Seizures Prevents Later Increases in Seizure‐induced Neuronal Injury , 2004, Epilepsia.

[22]  E. van Luijtelaar,et al.  Genetic Animal Models for Absence Epilepsy: A Review of the WAG/Rij Strain of Rats , 2003, Behavior genetics.

[23]  A. Waterman-Pearson,et al.  Changes in the EEG during castration in horses and ponies anaesthetized with halothane. , 2003, Veterinary anaesthesia and analgesia.

[24]  S. Une,et al.  Quantitative electroencephalography of medetomidine, medetomidine-midazolam and medetomidine-midazolam-butorphanol in dogs. , 2002, Journal of veterinary medicine. A, Physiology, pathology, clinical medicine.

[25]  A. Coenen,et al.  Electrophysiological and pharmacological characteristics of two types of spike-wave discharges in WAG/Rij rats , 2001, Brain Research.

[26]  W. Löscher,et al.  Anticonvulsant and proconvulsant effects of tramadol, its enantiomers and its M1 metabolite in the rat kindling model of epilepsy , 2000, British journal of pharmacology.

[27]  P. Wouters,et al.  Effects of tramadol on minimum alveolar concentration (MAC) of isoflurane in rats. , 1999, British journal of anaesthesia.

[28]  D. Graham,et al.  Seizures reported with tramadol. , 1997, JAMA.

[29]  B. Benson,et al.  Prospective multicenter evaluation of tramadol exposure. , 1997, Journal of toxicology. Clinical toxicology.

[30]  L. Arendt-Nielsen,et al.  The hypoalgesic effect of tramadol in relation to CYP2D6 * , 1996, Clinical pharmacology and therapeutics.

[31]  K. Otto,et al.  Differences in quantitated electroencephalographic variables during surgical stimulation of horses anesthetized with isoflurane. , 1996, Veterinary surgery : VS.

[32]  K. Otto,et al.  Comparison of Neurologic Responses to the Use of Medetomidine as a Sole Agent or Preanesthetic in Laboratory Beagles , 1992, Acta Veterinaria Scandinavica.

[33]  C. Gottesmann,et al.  Study of cortical spindles during sleep in the rat , 1978, Brain Research Bulletin.

[34]  F. Felgenhauer,et al.  [General pharmacological studies on tramadol, a potent analgetic agent (author's transl)]. , 1978, Arzneimittel-Forschung.