title: Acute toxicity of karlotoxins to mice.
abstract: Karlotoxins, polyketide derivatives produced by the dinoflagellate Karlodinium veneficum, are associated with fish kills in temperate estuaries world-wide. In this study, the acute effects of 3 pure karlotoxin analogs (KmTx 1, KmTx 3 and KmTx 2) have been examined in mice. Transient lethargy and increased respiratory rates were observed soon after dosing with the karlotoxins by intraperitoneal injection, but no deaths were recorded in animals dosed with KmTx 2 at up to 500 μg/kg or with KmTx 1 or KmTx 3 at up to 4000 μg/kg. Animals dosed intraperitoneally with KmTx 1 and KmTx 3 at 4000 μg/kg showed a pronounced decrease in food and water intake, lasting 3-4 days after dosing, accompanied by a significant decrease in body weight. After this time, the lost body weight was regained and the behavior and appearance of the mice remained normal throughout the following 10-day observation period. No effects were seen in mice dosed orally with KmTx 1 or KmTx 3 at a dose of 4000 μg/kg. It is concluded that contamination of seafood if it were to occur with these karlotoxins is unlikely to pose a major risk of acute intoxication in consumers.
authors.affiliation: Institute of Marine and Environmental Technology, University of Maryland Center for Environmental Sciences, 701 East Pratt Street, Baltimore, MD 21202, USA. Electronic address: place@umces.edu.
authors.forename: Allen R
authors.initials: AR
authors.lastname: Place
authors.affiliation: AgResearch, Ruakura Research Centre, Private Bag 3123, Hamilton, New Zealand.
authors.forename: R
authors.initials: R
authors.lastname: Munday
authors.affiliation: Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Private Bag 11222, Palmerston North, New Zealand.
authors.forename: J S
authors.initials: JS
authors.lastname: Munday
mesh_terms: D000818:Animals; D004333:Drug Administration Routes; D005260:Female; D008387:Marine Toxins; D051379:Mice; D011090:Polyenes / Q000008:administration & dosage / Q000633:toxicity*; D061065:Polyketides; D011714:Pyrans / Q000008:administration & dosage / Q000633:toxicity*; D023382:Toxicity Tests, Acute
chemical_list: D008387:Marine Toxins; D011090:Polyenes; D061065:Polyketides; D011714:Pyrans; C552184:karlotoxin 1; C550130:karlotoxin 2; C552185:karlotoxin 3
keywords: Acute toxicity; Karlotoxins; Mice