antiseizure action [10], the comparison of rapamycin and valproic acid effects was the additional aim
of the investigation.
Materials and Methods Experiments were performed on male Wistar rats with initial bodyweight 200-250 g. Animals were
kept in standard conditions (constant temperature 23o C and relative humidity 60%, 12 hrs dark/light cycles,
standard diet, and tap water were given ad libitum). They were acclimatized to laboratory conditions for at
least seven days before experimentation. At the stage of experimental work planning, principles outlined
ARRIVE guidelines and the Basel declaration (http://www.basel-declaration.org), including the 3R concept,
have been considered. All experiments were approved by Danylo Halytsky Lviv National Medical University
Bioethics Committee (UBC).
Kindled convulsions were induced, as described previously [6]. PTZ ("Sigma Aldrich") was given
intraperitoneally (i.p.) daily in a dose of 30.0 mg/kg for 21 days. The severity of convulsions was evaluated
according to the following criteria:
•
0, absence of symptoms of seizures;
•
1, facial tremor and separate myoclonic jerks;
•
2, whole-body clonic convulsions;
•
3, clonic convulsions of the whole body with rearings;
•
4, generalized clonic-tonic convulsions with rearings and falling;
•
5, repeated convulsions as at stage 4 or lethal outcome as a result of a seizure fit.
Those rats, which failed into generalized fits as a response to both 20-th and 21-th PTZ injections,
were taken for further observations and screening effects of compounds.
Rapamycin ("Pfizer", USA) was administered in doses of 0.3 – 3.0 mg/kg, i.p.
, and sodium valproate
("Sigma Aldrich", USA) was injected in doses of 50.0 – 250.0 mg/kg, i.p. Both compounds were dissolved in
5.0% methylcellulose (Methocel, "Sigma Aldrich"). Rapamycin and valproic acid were administered daily
for ten days. The last injection was performed in 60 min before testing PTZ administration. Control animals
were treated with Methocel only.
Data were analyzed by nonparametric analysis of variance ANOVA (Kruskall-Wallis test), followed
by a Mann-Whitney test when appropriate; p<0.05 was accepted as a defining statistical difference.