Changes in polyamine levels in response to acclimation salinity in gills of the blue crab Callinectes sapidus rathbun

Abstract The concentration of putrescine in gills 3, 4, 6 and 7 was approximately two-fold higher in gills acclimated to 35 ppt salinity than in those acclimated to 10 ppt salinity for 28 days ( c . 90 nmol/g wet weight vs 40 nmol/g wet weight, respectively). Spermine concentration was significantly higher in gills 6 and 7 than in gills 3 and 4 at 10 ppt salinity, and also was significantly higher than in gills 6 and 7 of crabs acclimated to 35 ppt salinity. Putrescine concentrations varied inversely and spermine concentrations varied directly with specific activity of Na + , K + -ATPase in all gills. On the basis of these data and other recent reports, we suggest that polyamines are involved in the regulation of osmotic and ionic homeostasis by interacting directly with the Na + , K+-ATPase enzyme.