Martentoxin, a 4,046 Da polypeptide toxin purified from the venom of the scorpion Buthus martensii Karsch, has been demonstrated to block large-conductance Ca2+-activated K+ (BKca) channels; however, its biologica...Martentoxin, a 4,046 Da polypeptide toxin purified from the venom of the scorpion Buthus martensii Karsch, has been demonstrated to block large-conductance Ca2+-activated K+ (BKca) channels; however, its biological roles are still largely unknown. In the present study, we investigated the pharmacological effects of martentoxin on regulating the production of nitric oxide induced by TNF-a in human umbilical vein endothelial cells (HU- VECs). We found that, 1, 10 and 100 ~tmol/L martentoxin decreased nitric oxide production by HUVECs ex- posed to 10 ng/mL TNF for 6, 12 and 24 hours. We further demonstrated that martentoxin inhibited the activity of iNOS and retarded the down-regulation of eNOS mRNA induced by TNF-a. Therefore, martentoxin could be a potential therapeutic agent for vascular diseases.展开更多
基金supported by the National Science Foundation of China(No.30271137No.30771831+1 种基金No.81072329)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘Martentoxin, a 4,046 Da polypeptide toxin purified from the venom of the scorpion Buthus martensii Karsch, has been demonstrated to block large-conductance Ca2+-activated K+ (BKca) channels; however, its biological roles are still largely unknown. In the present study, we investigated the pharmacological effects of martentoxin on regulating the production of nitric oxide induced by TNF-a in human umbilical vein endothelial cells (HU- VECs). We found that, 1, 10 and 100 ~tmol/L martentoxin decreased nitric oxide production by HUVECs ex- posed to 10 ng/mL TNF for 6, 12 and 24 hours. We further demonstrated that martentoxin inhibited the activity of iNOS and retarded the down-regulation of eNOS mRNA induced by TNF-a. Therefore, martentoxin could be a potential therapeutic agent for vascular diseases.