To determine whether the cyclic adenosine monophosphate (cAMP) mediated protein kinase signal transduction pathway is involved in the pyrogenic action of corticotropin releasing hormone (CRH) in rats. Methods Corticotropin releasing hormone, 2', 3 '-dideoxyadenosine (DDA) and adenosine-3', 5' (cyclic) monophosphorothionate, Rp-lsomer (Rp-cAMPS), were administered intracerebroventricularly (i.c.v.). The colonic temperature was measured using a thermistor, and the content of cAMP in the hypothalamus was determined by radioimmunoassay. Hypethalemic incubation was used to assess the effects of CRH on the content of cAMP in the hypothalamus in vitro. Results Microinjection (i.c.v.) of CRH (2.5 μg, 5.0 μg and 10 μg) caused increases in colonic temperature and the hypothalemus cAMP level in conscious rats. CRH increased hypothalemus cAMP level in vitro. The pyrogenic effects of CRH were abolished or markedly inhibited by prior injection (i. c. v. ) of an adenylate cyclase inhibitor, DDA (30 μg), or an inhibitor of cAMP-dependent protein kinase, Rp-cAMPS (15 μg). Conclusion cAMP mediates the pyrogenic action of centrally administered of CRH in rats, and protein kinase A may play an important role in the central CRH-induced fever. The cAMP-dependent protein kinase signal transduction pathway may be involved in the central mechanisms of the pyrogenic action of CRH in rats.

Objective To identify new recombinant antigens with potential for diagnosis of hemorrhagic fever with renal syndrom (HFRS) and establish reverse transcription-polymerase chain reaction-restriction fragments length polymorphism (RT-PCR-RFLP) for genotyping of hantavirus. Methods One group of primers was used to clone the full-length S genome segment and the partial S genorme segment of the N-terminal. The two cloned genes were both fusionally expressed and non fusionally expressed in the T7 system. The other group of primers was used to establish a RT-PCR method to detect RNAs in 37 virus isolates, 2 positive standard virus strains of hantavirus and 5 negative controls. The method for typing RFLP was set up by digesting the PCR products of 20 virus isolates with Ras Ⅰ and Hind Ⅲ. Results The non-fusionally expressed products with a working concentration of 1:10 000 by chapping enzyme-linked immunosorbent assay (cELISA), presented good biological activity though yields were lower than that of the fusionally expressed products.The specific component of the hantavirus genome (299 bp or 577 bp) wes seen in all viral samples. The genotyping of hantavirus showed that 9 out of the total were hantann (HTN) viruses, 8 were seol (SEO) viruses and 3 were not determined. Conclusions The good working titrer of expressed recombinant antigen showed that it has the potential to replace the natural antigen for detecting hantavirus antibodies. On comparison with cELISA, the detection rates for these two methods were 100% and 84.6%, and the coincidence rate was 84.6%. The former had a 15.4% higher sensitivity than the latter. The typing efficiency of RT-PCR-RFLP and sero-typing method was 85% (17/20) and 55% (11/20), respectively, showing that the former was 30% higher than the latter, while their results were highly consistant.

OBJECTIVETo clone and identify the mouse gene homologous to human hepatitis B virus (HBV) pre-S1 protein-binding protein (PS1BP).

METHODSThe human PS1BP cDNA sequence was used as the reference sequence to search homologous mouse cDNA sequence from GenBank established by National Center for Biotechnology (NCBI), National Institute of Health (NIH), for its homologous cDNA sequences of mouse by BLASTn tool. The characteristics of mouse PS1BP protein primary structure were predicted by online software. Finally the genomic DNA structure of mouse PS1BP was deduced and compared.

RESULTSThe mouse PS1BP was identified and consisted of 1455 nt, coding a protein of 484 aa. The identity of human and mouse PS1BP protein is 84.92% (411/484). The genomic DNA of mouse PS1BP consisted of 3 exons and 2 introns.

CONCLUSIONThe identification and characterization of mouse PS1BP cDNA and genomic DNA pave a way for further study of their structures and functions.

Amino Acid Sequence ; Animals ; Base Sequence ; Carrier Proteins ; genetics ; Cloning, Molecular ; Computational Biology ; DNA, Complementary ; genetics ; Databases, Nucleic Acid ; Hepatitis B Surface Antigens ; genetics ; Hepatitis B virus ; genetics ; Humans ; Mice ; Molecular Sequence Data ; Protein Precursors ; genetics ; Sequence Alignment ; Sequence Homology, Nucleic Acid