| Objective:(1) By building the lithium-pilocarpine seizures(LPS) model in adult rats, to study the anti-epileptic effects of scorpion venom(SV) and valproic acid(VPA), comparatively; (2) By observing the dynamic changes of ITGA2 in hippocampus on rats models after the intervention of SV, to investigate the influence of SV on the expression of ITGA2 and to explore the possible anti-epileptic mechanism. Methods:(1) 100 of 106 healthy male SD rats that belong to clean class were used to make LPS rats model,the rest is included in normal control group(n=6). LPS rats were then randomly divided into three groups:model group (n=40), VPA intervention group (n=40) and SV intervention groups (n=40). Intervention drugs were intragastric administrated. Normal control group and model group were administrated with distilled water; VPA intervention group was administrated with VPA (120mg·kg-1·d-1); SV intervention group was administrated with SV (0.3mg·kg-1·d-1). (2) For each group of LPS rats,20 rats were observed on behavioral performance in 28 days intervention period, seizures frequency and severity scale during 14-28 days were recorded and analyzed by Kruskal-Wallis Test. (3) The rest 20 rats from model group and SV intervention group were further divided into 5 subgroups (4 for each) based on the different intervention time (Id,3d,7d,14d,28d). Immunohistochemical technique was used to examine the expression of ITGA2 in Dentate Gyrus (DG), CA1 and CA3 of rat hippocampus among normal control group, model group and SV intervention group. Image analysis technology was also applied to analyze quantitatively the dynamic changes of ITGA2 and ANOVA test was to detect the difference between groups. Results:(1) Behavior performance in each group was as follows:①no seizure was observed in normal and SV controls during study period;②all rats in model group had seizure with severity grade no less than IV In acute phrase and a silence stage was found later lasting 8-14d. Chronic spontaneous seizure stage was after 15th and spontaneous recurrent seizure was its feature;③during observing period, SV and VPA intervention group had lower seizure frequency and severity compared with model group (P<0.05);④SV intervention showed smaller effect on the control of seizure frequency and severity than VPA (P<0.05). (2) Results of ITGA2 expression in hippocampus among normal control group, model group and SV intervention group:①all above three groups displayed ITGA2 expression in CA1 and CA3 of hippocampus and granule cell layer of DG, and ITGA2-IR positive cells were detected. ITGA2 expression in DG was more enhanced than that of CA1 with P<0.05 however no statistic difference was found when compared with CA3. Additionally the expression in CA3 and CA1 showed no difference (P>0.05) even though ITGA2 expression seemed higher distributed on the cell membrane and cytoplasm..②In normal controls, ITGA2 expression in hippocampus presented low.③In model group, ITGA2 expression was upregulation on the 1st day, and reached its peak at 14th day with gradual reduction after that time. Comparing with the normal group, ITGA2 expression in hippocampus in model group was enhanced at each observing time point (P<0.05 with the exception of 1d).④in SV intervention group, ITGA2 expression in hippocampus started to increase since the first day, and achieve the highest level at 14th day which was obvious lower than that in model group (P<0.05) and afterwards descended but failed to returned to the normal level at 28th day.⑤Compared with the normal group, ITGA2 expression in hippocampus in SV intervention group was enhance at each observation time point (P<0.05 with the exception of 1d); Compared with model group, in SV intervention group ITGA2 expression was weakened at all areas and observation time points apart from DG at the first day and CA1 at 3rd day; Whereas statistic difference (P<0.05) was only found in CA3 at 7th day and CA1, CA3, DG at 14th day and CA1, DG at 28th day. Conclusion:(1) SV has significant control effect on seizure severity and frequency in our studied LPS rats model. (2) SV is proved not as effective as VPA with regard to seizure control. We surmise it might be as the result of different effectiveness, therapeutic dosage and administration route. (3) In our study, no drug toxicity and death were presented which might suggest both VPA and SV have good therapeutic safety, (4) ITGA2 expression in hippocampus was enhanced in LPS rats with starting to rise at 1st day, arriving its top at 14th day and failing to recover to normal at 28th day. (5) ITGA2 expression in hippocampus by SV intervention was increased than in normal controls and lower than that in model group with the similar variation tendency. It might indicate that SV could partly suppress ITGA2 expression which plays a important role of anti-epilepsy. (6) SV might act as anti-epileptic drugs by suppressing ITGA2 expression on Laminin-integrins transmembrane system hence to reduce the chance of the mossy fiber sprouting. (7) new evidence was provided by our study that SV as an antiepileptic drug. Maybe new clues for exploring AEDs might be discovered form our research.
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