MC-LR toxicokinetics: analysis of free MC-LR levels by HLPC/MS in six tissues of mice orally exposed to the toxin.

SEDAN, DANIELA; FREITAS DE MAGALHÃES, VALÉRIA; LUCIANE, BANDÃO; LEDA, GIANNUZZI; DARÍO, ANDRINOLO

Florianopolis

Congreso; "The 17th international Conference on Harmful Algae"; 2016

"The 17th international Conference on Harmful Algae"

Oral route is one of the main routes of exposure to MC-LR, mainly through ingestion of contaminated water with this toxin. Although, toxicokinetics of MCs has been insufficiently discussed in the literature. The aim of this study was to evaluate the levels of MC-LR present in the main body compartments in mice orally exposed to repeated doses of MC-LR.One group of N: NIH Swiss mice was treated by gavage with one dose of 250 µgMC-LR/kg and 30 ´, 1 hr, 3hrs, 12hrs and 24 hrs after the administration blood, liver, intestine, lung, kidney and heart samples were taken. Another group of mice was treated by gavage with 4 doses of 250 µgMC-LR/kg administered every 48 hours. The same tissues samples were taken at 24 and 48 hours post administration. Heart MC-LR levels were not detected in all experiments developed. The tissues mainly involved in the uptake (intestine) and detoxification (liver and kidney) of MC-LR had equivalents toxin profile vs. time. The same occurred with toxins profile in blood and lung. Free MC-LR evidenced a different dynamic respect to the total toxin`s dynamic, mainly in the liver where showed no bioaccumulation of free MC-LR. The differences in processes and tissues that MC-LR has access in oral administration respect of i.p. administration could generate the different dynamics observed. Furthermore animals have shown a physiological adaptation to successive doses of MC-LR that allowed them to have low levels of free MC-LR in target organs such as liver.