Abstracts / Marine Environmental Research 50 (2000) 545±552
547
including preservation of epithelial cells, chloride cells and pillar cells in the central stroma. Cultures were exposed to 1 mM or 10 mm HgCl2 for up to 6 h. These cultures showed marked changes in the epithelium including swelling of cytosol, endoplasmic reticulum, and mitochondria and nuclear lysis. By 6 h, many cells were necrotic with ¯occulent intramatrical densities in mitochondria and interruption in plasmalemmal permeability. In many gill ®laments, only the pillar cells and capillaries remained intact. These studies show that skin and gill can be successfully cultured and that they remain essentially normal for up to 30 days. In addition, skin explants can serve as an important way to initiate monolayer cultures. They also show that gill and skin show responses to environmental/toxic injury that lead to cell death at higher doses. PII: S0141-1136(00)00234-8
Susceptibility to oxyradical toxicity in Antarctic, Arctic, and Mediterranean scallops F. Regoli a, M. Nigro b, S. Bompadre c, G.W. Winston d a Istituto di Biologia e Genetica, Universita' di Ancona, Italy Dipartimento di Morfologia Umana e Biologia Applicata, UniversitaÁ di Pisa, Italy c Istituto di Scienze Biomediche, Universita' di Ancona, Italy d Department of Toxicology, North Carolina State University, NC 27695, USA
b
Abstract We have used the total oxyradical scavenging capacity (TOSC) assay for quantifying the ability of biological samples to neutralize peroxyl (ROO.) and hydroxyl (.OH) radicals and peroxynitrite (PN). TOSC was assessed for three species of scallops, Adamussium colbecki (AC), Chlamys islandicus (CI) and Pecten jacobaeus (PJ), respectively from the Antarctic, Arctic and Mediterranean seas. TOSC values for ROO. were signi®cantly higher in AC indicating that this species is the more ecient scavenger of ROO.. Mediterranean scallops had the lowest TOSC for ROO.. AC had the highest scavenging capacity for .OH; the TOSC value was 3-fold greater than for CI and PJ. TOSC for PN was lower for all scallops as compared to that for ROO. or .OH. TOSC for microsomes was not signi®cantly dierent among the species for any ROS studied, and the percentage contribution to the speci®c TOSC for the various oxidants of microsomes of all scallops accounted for 1±3% of the total TOSC of the post-mitochondrial fraction. The speci®c TOSC of scallop microsomes for .OH was 10 times lower than that for ROO. or PN. TOSC is proposed as a quanti®able value of susceptibility to oxidative stress from aquatic pollution. PII: S0141-1136(00)00235-X