Ingestion of microcystins by Daphnia: Intestinal uptake and toxic effects

• Type: Article in International Scientific Journal
• Date: 2005

Authors

Rohrlack, T (Author) Other; Christoffersen, K (Author) Other; Dittmann, E (Author) Other; Nogueira, I (Author) Other; Vasconcelos, V (Author) FCUP; Borner, T (Author) Other

Journal

Title: Limnology and Oceanography

Vol. 50

Pages: 440-448

ISSN: 0024-3590

Publisher: Wiley-Blackwell

Indexing

ISI Web of Knowledge - 98 Citations

Scopus - 100 Citations

Scientific classification

FOS: Natural sciences > Earth and related Environmental sciences

Other information

Authenticus ID: P-000-4JX

DOI: 10.4319/lo.2005.50.2.0440

Abstract (EN): We investigated the intestinal uptake and adverse effects of microcystins ingested with Microcystis on Daphnia galeata. The gut structure, blood microcystin concentration, appearance, and movements of Daphnia fed Microcystis PCC 7806 or a microcystin-deficient PCC 7806 mutant were monitored over time. Microcystins were rapidly taken up from the digestive cavity into the blood. This process apparently required a preceding disruption of the gut epithelium by an as-yet-unknown Microcystis factor. Once microcystins entered the blood, they affected the neuromuscular communication or another life function that influences major muscle systems. Consequently, the beat rates of the thoracic legs, mandibles, and second antennae as well as the activity of the foregut decreased, whereas the midgut muscles were stimulated. Finally, the animals exhibited symptoms of exhaustion and died. The present results suggest that an ingestion of between 10.2 ng and 18.3 ng of microcystin per 1 mg of Daphnia body fresh weight is sufficient to kill D. galeata within 2 d.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 9