Tiagabine treatment is associated with neurochemical, immune and behavioural alterations in the olfactory bulbectomized rat model of depression.
BACKGROUND
Affective disorders are often associated with immune and neuroendocrine disturbances. However, little information on the modulatory effects of antiepileptics on endocrine and immune functions is available. Some novel antiepileptics, including tiagabine, are considered as potential antidepressants.


METHODS
We investigated the influence of tiagabine on stress hormone release, cellular immune function and behaviour in rats following olfactory bulbectomy (OB), a well-recognized animal model of depression.


RESULTS
Hyperlocomotion in the open field, typical for the OB rodents, was attenuated by repeated treatment with tiagabine (12 mg/kg/day) in a similar fashion to standard antidepressants. OB led to significantly decreased lymphocyte and increased neutrophil counts, and suppressed leukocyte phagocytosis. The OB-induced changes in leukocyte differential counts were not found in the tiagabine-treated group. The OB-induced reduction in plasma noradrenaline levels was normalized following tiagabine treatment.


CONCLUSIONS
The present data bring further evidence on the antidepressant-like action of tiagabine and encourage further research on its use in the treatment of affective disorders. The observed changes in immune and endocrine functions may contribute to its mood stabilizing effect.
Pistovcakova
J
J
Department of Pharmacology, Faculty of Medicine, Masaryk University, Brno, Czech Republic.
Dostalek
M
M
Sulcova
A
A
Jezova
D
D
D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D001923:Brain Chemistry / Q000187:drug effects*; D003345:Corticosterone / Q000097:blood; D003863:Depression / Q000523:psychology*; D018755:GABA Agonists / Q000494:pharmacology*; D007111:Immunity, Cellular / Q000187:drug effects*; D007958:Leukocyte Count; D007962:Leukocytes / Q000187:drug effects / Q000276:immunology; D049449:Luminescence; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D018377:Neurotransmitter Agents / Q000097:blood; D009504:Neutrophils; D009557:Nipecotic Acids / Q000494:pharmacology*; D009830:Olfactory Bulb / Q000502:physiology*; D010587:Phagocytosis / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D013315:Stress, Psychological / Q000097:blood; D000078308:Tiagabine
D018755:GABA Agonists; D018377:Neurotransmitter Agents; D009557:Nipecotic Acids; D003345:Corticosterone; D000078308:Tiagabine