Histopathological changes in gills of the estuarine crab Chasmagnathus granulata (Crustacea-Decapoda) following acute exposure to ammonia.

Dept. Ciências Fisiologicas, Lab. Zoofisiologia, Fundação Universidade Federal do Rio Grande, CP 474, Rio Grande, RS, 91206-900, Brazil.
Comparative Biochemistry and Physiology Part C Toxicology & Pharmacology (Impact Factor: 2.83). 02/2000; 125(2):157-64. DOI: 10.1016/S0742-8413(99)00093-6
Source: PubMed

ABSTRACT Histopathological effects of ammonia on the gills of the estuarine crab Chasmagnathus granulata (Dana, 1851) were evaluated after acute exposure to ammonia concentrations around LC(50) value (17.85 Mm). Disruption of pilaster cells and a subsequent collapse of gill lamellae were the main effects observed. Epithelial necrosis and hyperplasia were also detected. Significant (P<0.05) increases in pCO(2) and lactate, and significant decreases of pO(2) were detected in the haemolymph of ammonia-exposed crabs. These changes suggest that the observed histopathological damage affected gas exchange, possibly leading to death.

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