Ultrastructural observations in gills and hepatopancreas of prawn Macrobrachium malcolmsonii exposed to mercury

摘要: The juveniles of M. malcolmsonii were exposed to 24.1 microg l(-1) Hg fora period 21 days. gills and hepatopancreas test prawns sampled processed for electron microscopic observations. Mitochondria are the organelle most affected in prawns. number mitochondria electron-density matrix found be less in-folding cell membrane associated with was absent This suggests that operation mitochondrial pumps Vacuoles crystalline granular inclusions noted These suggestive metal-rich inorganic deposits or granules representing detoxified dumps Hg. In prawns, tubules exhibit vacuoles inclusion cytoplasm contains electron-dense granules, which indicate a storage detoxification shrunken attenuation its function. rough endoplasmic reticulum appeared vesiculated dilated. reactions denote hyperactivity reticulum. Membranous whorl-like structures myelin fibers residual bodies seen Such involvement lysosomal breakdown process. ultrastructural alterations compensatory mechanisms within enable it tolerate toxicity. However these would have an impact on cellular integrity such can taken as 'biomarkers' assessing pollution aquatic environment.