[Expression of δ subunit of γ-aminobutyric acid A in hippocampus induced by insular-kindled rats].

OBJECTIVE: To explore the expression of δ subunit-containing γ-aminobutyric acid(A) (GABA)(A) receptors in insular electrical kindled rats and analyze the significance of the findings. METHODS: A total of 48 male Sprague-Dawley rats were divided randomly into 3 groups: kindled, sham-operated and control. Kindled group: chronic insular electrical kindled models of rats established by electrical stimulation. Sham-operated group: the same method of the kindled group without electrical stimulation. CONTROL GROUP: without surgery. The number of hippocampal neurons of rat epilepsy, sham-operated and control groups were detected by Nissl staining. The hippocampal expressions of δ subunit of these groups were tested by immunohistochemistry. The mRNA of δ subunit of hippocampus of these groups was detected by quantitative-polymerase chain reaction (q-PCR). RESULTS: The findings of Nissl staining showed that there was no significant difference of the number of hippocampal neurons between epileptic and normal rats (P > 0.05). The findings of q-PCR showed that mRNA of δ subunit of the hippocampus of sham-operated and control groups represented much more than that of kindled group at Day 7 post-kindling (P < 0.01). The findings of immunohistochemistry showed that the hippocampal expression of δ subunit of sham-operated and control groups represented much more than that of kindled group at Day 7 post-kindling (P < 0.01). CONCLUSION: The hippocampal expression of δ subunit-containing GABA(A) receptors decreases in insular epilepsy. It may play an important role in the occurrence and development of insular epilepsy.