The effects of tributyltin (TBT) on circulating cells from the clam Tapes philippinarum were investigated in order to set up quick and reproducible in vitro bioassays to evaluate TBT toxicity in bivalve molluscs. Haemocytes, collected from adductor muscle of clams, were exposed for 60 min at 25 °C to sublethal concentrations of TBT (0.01, 0.05 and 0.1 µM) and the effects on Neutral Red uptake, and both superoxide dismutase and lysozyme activities were spectrophotometrically evaluated. Exposure of cells to 0.05 µM TBT caused significant increase (P < 0.05) in Neutral Red uptake compared to controls, whereas no differences resulted after exposure to 0.01 and 0.1 µM TBT. Enlarged lysosomes were observed in haemocytes exposed to 0.05 µM TBT. Moreover, in haemocytes treated with 0.05 and 0.1 µM TBT SOD activity exhibited a significant decrease (P < 0.05 and P < 0.01, respectively) with respect to controls. A significant decrease in lysozyme activity was also observed in haemocytes exposed to 0.05 (P < 0.01) and 0.1 µM TBT (P < 0.001). These results suggest a relationship between TBT exposure and alterations in functional responses of haemocytes in T. philippinarum. Proposed assays result sensitive, rapid and reproducible. They can be proposed as biomarkers, even though their responsiveness needs to be more fully evaluated in haemocytes collected after clam exposure in laboratory and field conditions.
In vitro effects of TBT exposure on functional responses of haemocytes in the clam Tapes philippinarum.
MATOZZO, VALERIO;BALLARIN, LORIANO;MARIN, MARIA
2002
Abstract
The effects of tributyltin (TBT) on circulating cells from the clam Tapes philippinarum were investigated in order to set up quick and reproducible in vitro bioassays to evaluate TBT toxicity in bivalve molluscs. Haemocytes, collected from adductor muscle of clams, were exposed for 60 min at 25 °C to sublethal concentrations of TBT (0.01, 0.05 and 0.1 µM) and the effects on Neutral Red uptake, and both superoxide dismutase and lysozyme activities were spectrophotometrically evaluated. Exposure of cells to 0.05 µM TBT caused significant increase (P < 0.05) in Neutral Red uptake compared to controls, whereas no differences resulted after exposure to 0.01 and 0.1 µM TBT. Enlarged lysosomes were observed in haemocytes exposed to 0.05 µM TBT. Moreover, in haemocytes treated with 0.05 and 0.1 µM TBT SOD activity exhibited a significant decrease (P < 0.05 and P < 0.01, respectively) with respect to controls. A significant decrease in lysozyme activity was also observed in haemocytes exposed to 0.05 (P < 0.01) and 0.1 µM TBT (P < 0.001). These results suggest a relationship between TBT exposure and alterations in functional responses of haemocytes in T. philippinarum. Proposed assays result sensitive, rapid and reproducible. They can be proposed as biomarkers, even though their responsiveness needs to be more fully evaluated in haemocytes collected after clam exposure in laboratory and field conditions.Pubblicazioni consigliate
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.