Regulatory effect of nerve growth factor on release of substance P in cultured dorsal root ganglion neurons of rat / 神经科学通报·英文版

<p><b>OBJECTIVE</b>To investigate the regulatory effects of nerve growth factor (NGF) on basal and capsaicin-induced release of neuropeptide substance P (SP) in primary cultured embryonic rat dorsal root ganglion (DRG) neurons.</p><p><b>METHODS</b>DRGs were dissected from 15-day-old embryonic Wistar rats. DRG neurons were dissociated and cultured, and then exposed to different concentrations of NGF (10 ng/mL, 30 ng/mL, or 100 ng/mL) for 72 h. The neurons cultured in media without NGF served as control. RT-PCR were used for detecting the mRNAs of SP and vanilloid receptor 1 (VR1) in the DRG neurons. The SP basal and capsaicin (100 nmol/L)-induced release in the culture were measured by radioimmunoassay (RIA).</p><p><b>RESULTS</b>SP mRNA and VR1 mRNA expression increased in primary cultured DRG neurons in a dose-dependent manner of NGF. Both basal release and capsaicin-evoked release of SP increased in NGF-treated DRG neurons compared with in control group. The capsaicin-evoked release of SP also increased in a dose-dependent manner of NGF.</p><p><b>CONCLUSION</b>NGF may promote both basal release and capsaicin-evoked release of SP. NGF might increase the sensitivity of nociceptors by increasing the SP mRNA or VR1 mRNA.</p>

Inhibition of HBV DNA replication and expression in 2.2.15 hepatoma cells infected with AFP-mediated HBX antisense RNA / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To study the specific expression of the antisense RNA against hepatitis B virus X (HBX) gene in hepatoblastoma cell line and its anti -HBV activity.</p><p><b>METHODS</b>HBX gene (nt.1370-1827) was amplified by PCR, then cloned into EB virus vector pEBAF which contained human alpha-fetoprotein promoter and enhancer. After transfected into 2.2.15 hepatoma cells and ECV304 human endothelial cells by lipofectin, northern blot, ELISA and real-time qualitative PCR were carried out to assay the expression of HBX mRNA, HBV antigens and HBV DNA level, respectively.</p><p><b>RESULTS</b>The HBX antisense RNA expression vector pEBAF-as-HBX which could be expressed specifically in 2.2.15 hepatoblastoma cells was successfully constructed. Both HBV DNA level and the expressions of hepatitis B virus surface antigen (HBsAg) and e antigen (HBeAg) in 2.2.15 hepatoblastoma cells were inhibited by pEBAF-as-HBX. Compared with those in sense control (pEBAF-s-HBX), the inhibitory rates of HBsAg, HBeAg, and HBV DNA were 37.9%, 36.8%, and 25%, respectively.</p><p><b>CONCLUSIONS</b>The pEBAF-as-HBX expression vector may lead to targeted-expression of HBX antisense RNA in hepatoma cells and shows great inhibition effect on HBV.</p>