| Physiological reactions of sea-basses juveniles (2-6 months) have been followed in laboratory after transfer to different salinities during Summer 1976 and 1977 : hyperhaline : 41 %. , euhaline : 30 %. , mesohaline medium : 9-10 %o , and oligohaline environments : 1-3%o . A lot of fish has been acclimated ina lagoon, at Certes, to 15-20, of salinity. The evolution of gill ATPases activities (Na+ + K+ and Mg2+ ) was followed. Results show different Na+ - K+ ATPase levels, in relationship with the salinity : - at 30 and 42 %c, the level is high at the beginning of Summer (22,3 _+ 2,8 moles Pi . mg Prot -1 . h-1 decreases at the end of Summer (10,8 _+ 0,5) then increases in the fall (30,0 +_ 4,7) ; - at 10 %=, , the enzyme's activity level is steadily low,... |
