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Journal of Toxicology
Volume 2011 (2011), Article ID 280304, 9 pages
Research Article

Acute Exposure to Microcystin-Producing Cyanobacterium Microcystis aeruginosa Alters Adult Zebrafish (Danio rerio) Swimming Performance Parameters

1Laboratório de Biologia Genômica e Molecular, Faculdade de Biociências, Pontifícia Universidade Católica do Rio Grande do Sul, Avenida Ipiranga 6681, 90619-900 Porto Alegre, RS, Brazil
2Instituto Nacional de Ciência e Tecnologia Translacional em Medicina (INCT-TM), Hospital de Clínicas, Rua Ramiro Barcelos 2350, 90035-003 Porto Alegre, RS, Brazil
3Laboratório de Neuroquímica e Psicofarmacologia, Faculdade de Biociências, Pontifícia Universidade Católica do Rio Grande do Sul, Avenida Ipiranga 6681, 90619-900 Porto Alegre, RS, Brazil
4Programa de Pós-Graduação em Farmacologia, Centro de Ciências da Saúde, Universidade Federal de Santa Maria, Avenida Roraima 1000, 97105-900 Santa Maria, RS, Brazil
5Curso de Medicina Veterinária, Universidade de Passo Fundo, Campus Universitário, Caixa Postal 611, 99001-970 Passo Fundo, RS, Brazil
6Unidade de Pesquisas em Cianobactérias, Prédio da Hidroquímica, Instituto de Oceanografia, Campus Carreiros da FURG, Caixa Postal 474, Rio Grande, RS, Brazil

Received 12 August 2011; Revised 15 September 2011; Accepted 22 September 2011

Academic Editor: J. J. Stegeman

Copyright © 2011 Luiza Wilges Kist et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Microcystins (MCs) are toxins produced by cyanobacteria (blue-green algae), primarily Microcystis aeruginosa, forming water blooms worldwide. When an organism is exposed to environmental perturbations, alterations in normal behavioral patterns occur. Behavioral repertoire represents the consequence of a diversity of physiological and biochemical alterations. In this study, we assessed behavioral patterns and whole-body cortisol levels of adult zebrafish (Danio rerio) exposed to cell culture of the microcystin-producing cyanobacterium M. aeruginosa (MC-LR, strain RST9501). MC-LR exposure (100 μg/L) decreased by 63% the distance traveled and increased threefold the immobility time when compared to the control group. Interestingly, no significant alterations in the number of line crossings were found at the same MC-LR concentration and time of exposure. When animals were exposed to 50 and 100 μg/L, MC-LR promoted a significant increase (around 93%) in the time spent in the bottom portion of the tank, suggesting an anxiogenic effect. The results also showed that none of the MC-LR concentrations tested promoted significant alterations in absolute turn angle, path efficiency, social behavior, or whole-body cortisol level. These findings indicate that behavior is susceptible to MC-LR exposure and provide evidence for a better understanding of the ecological consequences of toxic algal blooms.