实验大鼠泰泽菌检测方法的比较研究

应用酶消化及机械分离法分离出生10～15d的大鼠海马神经元，从形态学及电生理学方面鉴定细胞活性。结果表明，该法可获得形态和生理特性良好的单个海马神经元。用0．5μmol／L的TTx阻断Na^ 通道后，分别记录到典型的全细胞电压依赖性钾离子通道电流以及延迟整流钾通道电流。证实该方法适用于海马神经元膜片钳研究，对深入探讨药物和毒物对海马离子通道及信号转导机制的作用有重要价值。

Comparative Study on Detecting Clostridum Piliforme Infections in Laboratory Rats

Objective To evaluate the usefulness of nested-polymerase chain reaction (nested-PCR), indirect fluorescent antibody assay (IFA), immunosuppressive provocation tests, and histopathological diagnosis assays for detecting Clostridum Piliforme (C. Piliforme) infections in laboratory rats. Methods In this study, the nested-PCR primers, which we synthesized to amplify C. Piliforme 16S ribosomal DNA (rDNA) sequences as an identification system for this organism, were performed by using C. Piliforme and 15 non-C. Piliforme strains. Specimens taken from 20 immunosuppressive Wistar rats and 5 non-immunosuppressive SD rats and submitted to detect C. Piliforme by nested-PCR. Results The C. Piliforme reference strain revealed positive result indicated by a 196 bp specific fragment on gel, while 15 non-C. Piliforme standard strains gave negative results demonstrating that the inner primers should be specific for C. Piliforme tested. The nested-PCR would be able to detect as little as 10 pg C. Piliforme-DNA. Tissues samples taken from rats and submitted to detect C. Piliforme by nested-PCR were found negative results, and the results of nested-PCR and consistent with those of conventional bacteria identification tests and histopathological diagnosis assays. 25 serum samples taken from rats were submitted to detect C. Piliforme antibodies by IFA were found heterologous cross-reactive antigens such as some strains of Clostridia and Bacillus. Conclusion IFA is best used for colony surveillance, and follow-up testing may include immunosuppressive provaction tests. Confirmation of C. Piliforme infections is best performed by PCR, bacteria identification tests, and histopathological diagnosis assays. In our study, the results of nested-PCR are consistent with those of bacteria identification tests and histopathological diagnosis assays. The data have also demonstrated that the nested-PCR established here is a quick, reliable, sensitive and specific method for detecting C. Piliforme infections in laboratory rats.