[Effect of electroacupuncture on epileptic EEG and intracellular Ca2+ content in the hippocampus in epilepsy rats]

To study the underlying mechanism of electroacupuncture (EA) in relieving epilepsy in pentylenetetrazole (PTZ)-induced epilepsy rats.

Twenty SD rats were randomly divided into normal control, model, EA, Nimodipine groups, with 5 cases in each. Epilepsy model was established by intraperitoneal injection of PTZ (32.0 mg/kg), once daily for 28 days. EA (100 Hz, 0.6 mA) was applied to "Baihui" (GV 20) and "Dazhui" (GV 14), once daily for 7 days. For Nimodipine group, the rats were given with nimodipine (0.25 mg/kg, i.p.), once daily for 7 days. Electroencephalogram (EEG) was recorded and the fluorescence intensity of Ca2+ of the hippocampus tissue sections was detected by laser scanning confocal microscope (LSCM) after incubation in artificial cerebrospinal fluid containing Flou-3/AM (10 micromol/L) and pluronic F-127 (5 microl).

Compared with model group, the latencies of epileptic EEG seizure prolonged obviously (P < 0.05), and epileptic EEG seizure frequencies decreased significantly (P < 0.05) in EA and Nimodipine groups. The fluorescence intensity of intracellular Ca2+ in hippocampus tissue in model group was obviously higher than that in control group (P < 0.01). In comparison to model group, Ca2+ levels in EA and Nimodipine groups lowered considerably (P < 0.05, P < 0.01). No significant differences were found between EA and Nimodipine groups in the aforementioned 3 indexes (P > 0.05).

EA has an obvious anti-epileptic effect, which may be closely related to its effect in downregulating the increased hippocampal Ca2+ level in PTZ-kindled epilepsy rats.