Two novel compounds, named sphaerophyside SC and SD were isolated from the ethanolic extract of the seeds of Sphaerophysa salsula. The structures of the compounds were elucidated on the basis of the NMR data, especia...Two novel compounds, named sphaerophyside SC and SD were isolated from the ethanolic extract of the seeds of Sphaerophysa salsula. The structures of the compounds were elucidated on the basis of the NMR data, especially the 2D NMR technique.展开更多
Extracellular adenosine 5'-triphosphate (ATP) has been established as a neurotransmitter or neuromodulator in both the periphe- ral and central nervous systems,in addition to diverse intracellular roles of it.P2 p...Extracellular adenosine 5'-triphosphate (ATP) has been established as a neurotransmitter or neuromodulator in both the periphe- ral and central nervous systems,in addition to diverse intracellular roles of it.P2 purinergic receptors,the receptors of ATP,are classified into two subfamilites,ionotropic P2X and metabotropic P2Y receptors.Recent studies suggest that ATP play a significant role in facilitating perpheral and spinal nociceptive transmission via P2X receptors.However,we demonstrated that at the supraspinal level P2X receptor agonists produce an antinociception.On the other hand,the activation of some subtypes of P2Y receptors in the spinal cord caused inhibitory effects on nociceptive transmission.Thus,P2X and P2Y receptors are suggested to be related to diverse roles in nociceptive functions at peripheral,spinal and supraspinal levels.We would like to take an overview about the significance of P2X and P2Y receptors in nociception and antinociception.展开更多
To elucidate the cellular and molecular mechanism of cerebral ischemia-induced neuronal apoptosis mediated by nitric oxide (NO) in the brain,we investigated:(1)cell death in hippocampal CA1 neurons of rats after a rra...To elucidate the cellular and molecular mechanism of cerebral ischemia-induced neuronal apoptosis mediated by nitric oxide (NO) in the brain,we investigated:(1)cell death in hippocampal CA1 neurons of rats after a rransient four vessel occlusion (4VO)/reperfusion and (2) apoptosis induced by NOC18(NO releaser) using SHSY5Y cells,a human neuroblastoma cell line.We found that 4VO caused expression of inducible type of NO synthase (iNOS) in glial cells and neuronal apoptosis in CA1 region of rats.Next we examined in vitro apoptotic effects of NOC18 on SHSY5Y cells and suggest that NO decrease mitochondrial membrane potential,release cytochrome C from mitochondria,activates caspase-3,degrade inhibitor of caspase-activated DNase(Icad),and activated DNase translocate into nucleus and induce DNA fragmentation.Thus we conclude that the excess amount of NO produced by glial iNOS at cerebral ischemia could be involved in neuronal apoptosis in CA1 region.Regarding NO action on neurons,we further obtained that NO propects neuronal apoptosis in PC12 cells perhaps by nitrosylation of caspase,subsequent reduction of proteolytic activity.Taken together,we suggest that NO seem to exert dual effects(toxic and beneficial) on neuronal apoptosis,the one (toxic);apoptosis-induction throuth the decrease in mitochondrial membrane potentials and cytochrome C release and the othe (beneficial);protection against apoptosis through the inhibition of caspase activity.展开更多
文摘Two novel compounds, named sphaerophyside SC and SD were isolated from the ethanolic extract of the seeds of Sphaerophysa salsula. The structures of the compounds were elucidated on the basis of the NMR data, especially the 2D NMR technique.
文摘Extracellular adenosine 5'-triphosphate (ATP) has been established as a neurotransmitter or neuromodulator in both the periphe- ral and central nervous systems,in addition to diverse intracellular roles of it.P2 purinergic receptors,the receptors of ATP,are classified into two subfamilites,ionotropic P2X and metabotropic P2Y receptors.Recent studies suggest that ATP play a significant role in facilitating perpheral and spinal nociceptive transmission via P2X receptors.However,we demonstrated that at the supraspinal level P2X receptor agonists produce an antinociception.On the other hand,the activation of some subtypes of P2Y receptors in the spinal cord caused inhibitory effects on nociceptive transmission.Thus,P2X and P2Y receptors are suggested to be related to diverse roles in nociceptive functions at peripheral,spinal and supraspinal levels.We would like to take an overview about the significance of P2X and P2Y receptors in nociception and antinociception.
文摘To elucidate the cellular and molecular mechanism of cerebral ischemia-induced neuronal apoptosis mediated by nitric oxide (NO) in the brain,we investigated:(1)cell death in hippocampal CA1 neurons of rats after a rransient four vessel occlusion (4VO)/reperfusion and (2) apoptosis induced by NOC18(NO releaser) using SHSY5Y cells,a human neuroblastoma cell line.We found that 4VO caused expression of inducible type of NO synthase (iNOS) in glial cells and neuronal apoptosis in CA1 region of rats.Next we examined in vitro apoptotic effects of NOC18 on SHSY5Y cells and suggest that NO decrease mitochondrial membrane potential,release cytochrome C from mitochondria,activates caspase-3,degrade inhibitor of caspase-activated DNase(Icad),and activated DNase translocate into nucleus and induce DNA fragmentation.Thus we conclude that the excess amount of NO produced by glial iNOS at cerebral ischemia could be involved in neuronal apoptosis in CA1 region.Regarding NO action on neurons,we further obtained that NO propects neuronal apoptosis in PC12 cells perhaps by nitrosylation of caspase,subsequent reduction of proteolytic activity.Taken together,we suggest that NO seem to exert dual effects(toxic and beneficial) on neuronal apoptosis,the one (toxic);apoptosis-induction throuth the decrease in mitochondrial membrane potentials and cytochrome C release and the othe (beneficial);protection against apoptosis through the inhibition of caspase activity.
