The protective effect of nerve growth factor on PC12 cells to lipopolysaccharide injury / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To investigate the effect of nerve growth factor (NGF) on lipopolysaccharide (LPS) injury and activation of nuclear factor-kappa B in PC12 cells.</p><p><b>METHODS</b>In order to set injury models, the PC12 cells were incubated in different concentration of LPS. Cells were cultured in the culture and were reduced by LPS, and then cells were treated by NGF of various concentrations. The cell viability was determined by methyl thiazolyl tetrazolium (MTT) assay, cellular morphology was observed under inverted microscope and fluorescence microscope, and the content of NF-kappaB was assessed by RT-PCR.</p><p><b>RESULTS</b>(1) The viability of PC12 cell was decreased with concentration of LPS increasing. (2) The cellular morphology change showed that NGF had an ability to reduce LPS injury. (3) The result of RT-PCR showed that the content of NF-kappaB in LPS injury was more than the normal and treated cell, and the treated one was close to the normal one.</p><p><b>CONCLUSION</b>The reports about NGF in brain cells repair after inflammatory are very small. And our study is about that NGF can protect the PC12 cell from LPS injury, and this mechanism possible bears on the activation of NF-kappaB.</p>

Effects of sinomenine on intracellular free calcium concentration and the activity of protein kinase in cultured rabbit aortic smooth muscle cells / 中国应用生理学杂志

<p><b>AIM</b>To explore the effects of sinomenine(Sin) on intracellular free calcium ([Ca2+]i) and the activity of PKC (protein kinase C) of the cultured aortic vascular smooth muscle cells (VSMC) during ischemia and hypoxia.</p><p><b>METHODS</b>The effect of Sin on changes in [Ca2+]i were determined in cultured rabbit VSMC after exposure to high K+, norepinephrine (NE) and caffeine (Caf). Fluorescent Ca2+ -indicater fura-2/AM was used. The effects of Sin were compared with that of verapamil (Ver). The hypoxia model was made, then the activity of PKC was measured by y scintillation counting instrument.</p><p><b>RESULTS</b>Sin (10 x 10(-6) mol x L(-1), 3 x 10(-5) mol x L(-1) 10(-4) mol x L(-1)) inhibited the elevation of [Ca2+]i induced by high K+ -depolarization in a concentration dependent manner. In addition, Sin inhibited the elevation of [Ca2+]i induced by NE in the presence of extracellular Ca2+. In the absence of extracellular Ca2+, Sin (3 x 10(-5) mol.L(-1)) also had no blocking effect on the NE-induced [Ca2+]i increase. It was found that the activity of PKC treated with Sin in VSMC cytoplasm and cell membrane in normal condition increased, the activity of PKC in cytoplasm in ischemia and hypoxia situation increased, but the activity of PKC in cell membrane decreased. When VSMC was treated with Sin, the activity of PKC in cytoplasm decreased and that of cell membrane increased.</p><p><b>CONCLUSION</b>The results suggest that Sin might decrease the[Ca2+] i of VSMC by blocking both VDC and ROC, could regulate the PKC activities induced by ischemia and hypoxia.</p>

Cellular uptake behavior of antisense oligodeoxynucleotides polymethacrylate submicroparticles / 药学学报

<p><b>AIM</b>To survey the uptake behavior and subcellular distribution of antisense oligodeoxynucleotide polymethacrylate submicroparticles (AS-ODN-SMP) and infer its mechanism in MGC cell lines.</p><p><b>METHODS</b>MGC cells were incubated at certain concentration of AS-ODN-SMP or AS-ODN for 8 h at 4 degrees C or 37 degrees C. Then the fluorescence oligodeoxynucleotide- labeled cells were counted by flow cytometer and the intracellular fluorescence intensity was determined after incubated with chloroquine for 2 h.</p><p><b>RESULTS</b>Cellular uptake of oligodeoxynucleotides was significantly increased following application of AS-ODN-SMP and total intracellular fluorescence intensity was enhanced by 683 folds with the vehicle concentration of 20 microg x mL(-1). AS-ODN-SMP entranced to cells profoundly with temperature-dependent manner. Rare cells took on fluorescence when incubated at 4 degrees C, while 37 degrees C they were significantly increased. But the intracellular fluorescence intensity appeared same level in present or absent of chloroquine.</p><p><b>CONCLUSION</b>With the help of polyacrylate submicroparticles, oligonucleotides efficiently entranced the cells via endocytosis and could successfully escape the degradation in lysosome.</p>