V. Matozzo et al., Effects of copper and cadmium exposure on functional responses of hemocytes in the clam, Tapes philippinarum, ARCH ENV C, 41(2), 2001, pp. 163-170
Citations number
60
Categorie Soggetti
Environment/Ecology,"Pharmacology & Toxicology
Journal title
ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY
The effects of Cu and Cd on functional responses of hemocytes in Tapes phil
ippinarum, a Veneridae clam widespread in the lagoon of Venice, were evalua
ted. Bivalves were exposed for 7 days to various concentrations Of CuCl2 .
2H(2)O (0, 10, 60, and 110 mug/L) and CdCl2 . H2O (0, 150, 300, and 450 mug
/L). Hemocytes were collected from exposed clams, and the effects of Cu and
Cd on phagocytosis, Neutral Red retention capacity, superoxide dismutase,
and cytochrome oxidase activities were investigated. Hemocytes from animals
exposed to Cu showed a significant decrease in phagocytic activity, wherea
s no inhibition was observed in cells from Cd-exposed animals. Diffusion of
Neutral Red into the cytosol, an index of lysosomal membrane alteration, w
as enhanced by high concentrations of both metals. Different results in bio
chemical parameters were observed. Exposure to 60 and 110 mug Cu/L caused a
significant reduction in hemocyte superoxide dismutase activity, whereas n
o changes resulted after Cd exposure. Increased cytochrome oxidase activity
was observed in hemocytes from mollusks exposed to 60 mug Cu/L and 300 mug
Cd/L; no significant differences were found in cells from bivalves exposed
to 110 mug Cu/L and 450 mug Cd/L. These results suggest a relationship bet
ween heavy metal exposure and alterations in functional responses of hemocy
tes in T. philippinarum and indicate that the type of observed effects vary
with the nature and concentration of heavy metals. Moreover, the data obta
ined in the analyzed clam support the possibility of using it as sentinel o
rganism in biomonitoring studies, even if used biomarkers will be further e
valuated in field conditions.