The effects of H2O2 were evaluated in the estuarine worm Laeonereis acuta (Polychaeta, Nereididae) collected at the Patos Lagoon estuary (Southern Brazil) and maintained in the laboratory under controlled salinity (10 psu diluted seawater) and temperature (20 degrees C). The worms were exposed to H2O2 (10 and 50 microM) for 4, 7, and 10 days and the following variables were determined: oxygen c...

Nereidae are vital to the functioning of estuarine ecosystems and are major components in the diets of over-wintering birds and commercial fish. They use environmental cues to synchronize reproduction. Photoperiod is the proximate cue, initiating vitellogenesis in a temperature-compensated process. The prevailing paradigm in Nereidae is of a single 'juvenile' hormone controlling growth and repr...

In crustacean muscle, earthworm longitudinal muscle, leech longitudinal muscle and barnacle muscle the major role in the production of the action potential is played by divalent cations rather than sodium ions, which are believed to be most important in many other excitable cells (Fatt & Ginsborg, 1958; Fatt & Katz, 1953; Werman, McCann & Grundfest, 1961; Hagiwara, Chichibu & Naka, 1964; Hagiwa...