The effects of organic and inorganic lithium salts assessed in rat primary generalized seizure model

Background. Lithium salts are used in psychiatry and may exhibit neuroprotective effects due to anion constituents.

Objective: to study a dose-dependent effect of oral lithium ascorbate (LiAsc) and lithium carbonate on manifestation and severity of primary generalized seizures caused by thiosemicarbazide in rats in vivo.

Material and methods. The study was conducted on 30 Wistar white male rats weighing 200–300 g in five groups: control, lithium carbonate 5 mg/kg, LiAsc 5, 10, 15 mg/kg/day, administered by probing for 14 days. The model of primary generalized seizures was reproduced by intraperitoneally administered 28 mg/kg thiosemicarbazide. The degree of neurological deficit was assessed based on seizure indicators (latency period before seizures, number of seizures and startles, clonic seizures, etc.). Histopathological studies of brain tissue were carried out using morphometry of histological sections on BioVision image analyzer (Austria).

Results. A course of carbonate and LiAsc significantly reduced seizure duration. The use of LiAsc at doses of 10–15 mg/kg/day not only significantly shortened seizure duration (p=0.01), but also increased the latent period before seizures (p=0.03), reduced the number of seizures (р<0.05) as well as rate of developing tonic extension (р=0.01).

Conclusion. LiAsc at dose of 10 mg/kg/day is sufficient for reducing neurological deficits in thiosemicarbazide-induced seizure model, further confirmed by the data of brain histopathological examination and morphometric analysis.

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