title: Effects of huwentoxin-I on catecholamines in cultured PC12 cells.
abstract: The measurement of catecholamines in biological samples remains a current analytical challenge in the study on neurotransmitter release, although much effort has been devoted toward the relevant methodology. Here we first established a fluoresence-based method for the quantitative determination of catecholamines and then applied it to the investigation of effects of huwentoxin-I (HWTX-I), a peptide neurotoxin, on catecholamines in cultured PC12 cells. The results showed that treatment with HWTX-I at different concentrations (10, 50, 100 and 1000 nM) for 20 min significantly increased dopamine (DA) content in the culture medium (p < 0.01), with ∼1.6-fold increase compared with that of the control at the highest concentration tested. Within 20 min, DA content in the medium increased with increasing the treatment time. In contrast, HWTX-I decreased norepinephrine (NE) content in the medium. However, after the PC12 cells were treated with HWTX-I, the intracellular contents of both DA and NE were kept at a relatively constant level. These data suggest that HWTX-I differentially affects the DA and NE of the neuroendocrine cells, with enhancing the actions of DA and weakening those of NE.
authors.affiliation: a Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education , College of Life Sciences, Hunan Normal University , Changsha , P.R. China.
authors.forename: Jia
authors.initials: J
authors.lastname: Chen
authors.forename: Zhipan
authors.initials: Z
authors.lastname: Dai
authors.forename: Qian
authors.initials: Q
authors.lastname: Lei
authors.forename: Shuai
authors.initials: S
authors.lastname: Yan
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
authors.forename: Xianchun
authors.initials: X
authors.lastname: Wang
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D002395:Catecholamines / Q000378:metabolism*; D002453:Cell Cycle / Q000187:drug effects; D003470:Culture Media / Q000032:analysis; D004298:Dopamine / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D055099:Neuroendocrine Cells / Q000187:drug effects / Q000378:metabolism; D009638:Norepinephrine / Q000378:metabolism; D016716:PC12 Cells; D051381:Rats; D030162:Reptilian Proteins / Q000494:pharmacology*; D013111:Spider Venoms / Q000494:pharmacology*
chemical_list: D002395:Catecholamines; D003470:Culture Media; D030162:Reptilian Proteins; D013111:Spider Venoms; C083624:huwentoxin I; D004298:Dopamine; D009638:Norepinephrine
keywords: Dopamine; PC12 cell; fluorometric assay; huwentoxin-I; norepinephrine