• BMB Reports
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• v.40 no.3
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• pp.302-314
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• 2007

N type calcium channels (CaV2.2) play a key role in the gating of transmitter release at presynaptic nerve terminals. These channels are generally regarded as parts of a multimolecular complex that can modulate their open probability and ensure their location near the vesicle docking and fusion sites. However, the proteins that comprise this component remain poorly characterized. We have carried out the first open screen of presynaptic CaV2.2 complex members by an antibody-mediated capture of the channel from purified rat brain synaptosome lysate followed by mass spectroscopy. 589 unique peptides resulted in a high confidence match of 104 total proteins and 40 synaptosome proteome proteins. This screen identified several known CaV2.2 interacting proteins including syntaxin 1, VAMP, protein phosphatase 2A, $G_{o\alpha}$, G$\beta$ and spectrin and also a number of novel proteins, including clathrin, adaptin, dynamin, dynein, NSF and actin. The unexpected proteins were classified within a number of functional classes that include exocytosis, endocytosis, cytoplasmic matrix, modulators, chaperones, and cell-signaling molecules and this list was contrasted to previous reports that catalogue the synaptosome proteome. The failure to detect any postsynaptic density proteins suggests that the channel itself does not exhibit stable trans-synaptic attachments. Our results suggest that the channel is anchored to a cytoplasmic matrix related to the previously described particle web.

• Journal of Ginseng Research
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• v.23 no.1 s.53
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• pp.38-43
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• 1999

Ginseng total saponins (ginsenosides) are biologically active main ingredients of Panax ginseng. In present study, we have investigated whether pretreatment of ginsenosides inhibited capsaicin-induced pain at the spinal level, in the view that capsaicin causes substance P (SP) release from primary afferents. Ginsenosides relieved capsaicin-induced pain in a dose-dependent manner. The $ED_{50}$ of the effect was 43 (20-93, $95\%$ C.I.) ${\mu}g/mouse$. We investigated excitatory amino acids-induced nociceptive responses in mice, because these agents are also involved in nociceptive transmission in the spinal cord. Coadministration of ginsenosides with N-methyl-D-aspartate (NMDA) or kainate via i.t. inhibited NMDA- but not kainate-induced pain behaviors. The $ED_{50}$ for the inhibition of NMDA-induced pain by ginsenosides was 37 (21-66, $95\%$ C.I.) ${\mu}g/mouse$. These results suggest that the ginsenosides-induced antinociception results from blocking of pain transmitter-induced nociceptive information at the spinal level.