title: Selective stimulation of Ca2+ flux in cells by maitotoxin.
abstract: Maitotoxin elicits a dose-dependent stimulation of 45Ca2+ influx in glioma C6, pheochromocytoma PC12, insulinoma HIT and human blood cells, while having no effect in liposomes. In HIT cells maitotoxin also elicited influx of 86Rb+ greater than 22Na+ greater than 54Mn2+, but the stimulation was far less than for 45Ca2+. Stimulation of 45Ca2+ influx was blocked by Ni2+, Co2+, Cd2+ and Mn2+, and markedly reduced by Ba2+. Divalent cations, in particular Ca2+, Ba2+, Mn2+ and Cd2+, enhanced influx of the monovalent cations 22Na+ and 86Rb+.
authors.affiliation: Laboratory of Bioorganic Chemistry, NIDDK, National Institutes of Health, Bethesda, MD 20892.
authors.forename: M
authors.initials: M
authors.lastname: Murata
authors.forename: F
authors.initials: F
authors.lastname: Gusovsky
authors.forename: T
authors.initials: T
authors.lastname: Yasumoto
authors.forename: J W
authors.initials: JW
authors.lastname: Daly
mesh_terms: D000818:Animals; D002118:Calcium / Q000097:blood / Q000378:metabolism*; D015220:Calcium Channels / Q000187:drug effects; D002132:Calcium Radioisotopes; D002412:Cations; D002713:Chlorine / Q000378:metabolism; D006224:Cricetinae; D004305:Dose-Response Relationship, Drug; D008081:Liposomes / Q000378:metabolism; D008345:Manganese / Q000378:metabolism; D008387:Marine Toxins / Q000494:pharmacology*; D035964:Oxocins; D011868:Radioisotopes; D051381:Rats; D012414:Rubidium Radioisotopes; D012979:Sodium Radioisotopes; D014407:Tumor Cells, Cultured; D000095702:Polyether Toxins
chemical_list: D002118:Calcium; D015220:Calcium Channels; D002132:Calcium Radioisotopes; D002412:Cations; D002713:Chlorine; D008081:Liposomes; D008345:Manganese; D008387:Marine Toxins; D035964:Oxocins; D011868:Radioisotopes; D012414:Rubidium Radioisotopes; D012979:Sodium Radioisotopes; C020394:maitotoxin; D000095702:Polyether Toxins