Abstracts

RATIONALE: We recently identified a novel gene, named B/K(Brain/Kidney), which is mainly expressed in rat brain and kidney. B/K encodes a 474-amino acid protein having two C2-like domains that is homologous to the C2 domain present in protein kinase C. In the present study, we examined B/K expression in kainic acid-induced rat seizure model. METHODS: KA was injected intraperitoneally into adult rats. For the dose-dependent study, KA at the dose of 4, 7, 10, 13, and 20 mg/kg were injected, and rats were sacrificed at three hours after the injection of KA. For the time-dependent study, rat were killed at the indicated times (1, 3, 5, 7 and 24 hours) following KA (10 mg/kg) injected. B/K expression and neuronal cell death were examined by immunochemical methods. RESULTS: B/K was rapidly and markedly expressed by the intraperitoneal injection of KA (kainic acid) in the hippocampus in dose- and time-dependent manners, reached the peak level at three hours in the CA3 and hilus, and at five hours in the CA1 and CA2. However, only mild induction was detected in the dantate gyrus. Neuronal cell loss was evident in the hippocampus and dentate gyrus by KA treatment, in particular the cells which expressed high level of B/K began to disappear about two hours after they reached maximum levels. CONCLUSIONS: These findings suggest a possible role for B/K in the generation or regulation of kainic acid-induced seizures and neuronal cell death