Effect of cedemex on cAMP and cGMP levels of different brain areas in morphine withdrawal rats / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the effect of Cedemex on cAMP and cGMP contents in different brain regions in morphine withdrawal rats precipitated by naloxone.</p><p><b>METHOD</b>A physical morphine dependent model of rats was established by subcutaneous injection of morphine in gradually increasing dosage within 7 days. cAMP and cGMP contents of VTA, cortex and hippocampus of the rat brains were determined by radioimmunoassay.</p><p><b>RESULT</b>The morphine withdrawal symptoms of rats were relieved significantly by ig Cedemex. Compared with the controls, cAMP content in the region of VTA, cortex and hippocampus of the morphine dependent rats were significantly higher (P < 0.05), while cGMP contents in those regions were significantly lower (P < 0.05). cAMP contents in the area of VTA, cortex and hippocampus of the morphine dependent rats were significantly reduced, while cGMP contents were significantly increased by ig Cedemex.</p><p><b>CONCLUSION</b>Cedemex may significantly attenuate the morphine withdrawal symptoms in rats. The mechanism of this effect may be related to adjusting the contents of cAMP and cGMP in some brain regions.</p>

Effect of manganese on apoptosis in striatum neurons of rats / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To explore the mechanism of neurotoxicity induced by manganese, and observe the effects on the apoptosis of neurons in rat striatum.</p><p><b>METHODS</b>SD rats were divided into four groups, six rats each group. Three dose groups were exposed to high, middle, and low level of MnCl(2). At the end of experiment, all rats of the exposed groups and control group were decapitated, their striatums were removed and the Mn content of striatum, the apoptotic morphology, ratio and ultrastructural organization were analyzed.</p><p><b>RESULTS</b>The Mn content of striatum and apoptosis index of the three dose groups exposed to high, middle, and low level of Mn were significantly higher than control group (P < 0.05). The Mn content of striatum of the three dose groups exposed to high, middle, low level of MnCl(2) and control group were 2.98 +/- 0.52, 2.75 +/- 0.37, 2.61 +/- 0.73, 0.60 +/- 0.20 respectively. The apoptosis index of striatum of the three dose groups exposed to high, middle, low level of MnCl(2) and control group were 24.83 +/- 5.98, 17.00 +/- 5.33, 15.33 +/- 2.58, 2.83 +/- 0.41 respectively, and following higher level dose, the apoptosis index increased. The nucleus of neurons in striatum become smaller, condensed, etc, and these character showed apoptosis of neurons.</p><p><b>CONCLUSION</b>Mn can result in apoptotic morphology and increase level of apoptosis in striatum. The level of apoptos varies with Mn concentration.</p>

Effect of manganese on cytosolic free calcium concentration in cortical neurons / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the change of free Ca(2+) in cytoplasma in the neurotoxicity of the manganese (Mn).</p><p><b>METHODS</b>The cortical neurons were separated from the neonatal Wistar rats and cultured in vitro. The neurons were grouped as the Mn-treated groups and the untreated group. The neurons in the Mn-added groups were incubated in the culture media containing lower, medium and high dosage manganese chloride (MnCl(2 x 4) H2O) with the concentration at 0.2, 0.6, 1.0 mmol/L respectively. Meanwhile, neurons in control were cultured in the normal culture media. All treatments stopped 24 h later. Neurons were labeled Ca(2+) sensitive prober, Fluo-3/AM. The fluorescence intensity of Fluo-3 combined with Ca(2+) was examined by LSCM (Laser scanning confocal microscope) and was treated by the picture analysis technique. The intensity was equal to the free Ca(2+) concentrations in cytoplasma of neurons.</p><p><b>RESULTS</b>MnCl(2) can induce free Ca(2+) overloaded in cytoplasma of neurons, but the increasing degree varied in MnCl(2) dosage. Cytoplasma Ca(2+) concentration in the moderate dosage The moderate dosage MnCl(2) group and the high dosage MnCl(2) group were significantly higher than that in the lower dosage MnCl(2) group and the control group (P < 0.05).</p><p><b>CONCLUSION</b>The Ca(2+) overload is involved in the neurotoxicity of manganese, and a dosage response relationship is found between the manganese chloride dose and Ca(2+) overload in cortical neurons.</p>