Variations des zymogrammes estérasiques chez les larves de Palaemon serratus soumises à différentes durées de choc thermique

Palaemon serratus at larval stage 2, acclimatized at 16°, were subjected to a temperature increase of 15° for periods of 5, 20 or 40 min with or without return to the initial temperature for 12 h. The soluble protein concentration of larvae subjected to a thermal shock of 20 min duration is lower than in control larvae. Total esterase-2C activity per mg of soluble protein after a thermal shock of 20 min duration is less than in control larvae but, in contrast with larvae subjected to a shock of 40 min duration, the initial activity is restored after 12 hours. Esterase-2C activity zymograms, after polyacrylamide gradient gel electrophoresis, show twelve isozymes. The activity of each isozyme examined varies according to the duration of the thermal shock.