The effects of cortisoland actinomycin D injections on choloride cells and branchial N+---K+-ATPase in rainbow trout (Salmo gairdneri)

Injections of cortisol, actinomycin D, or combined administration of the hormone and the antiobiotic did not effect rainbow trout (Salmo gairdneri) branchial Na⁺K⁺-ATPase activity. Numbers of chloride cells also did not change following cortisol and actinomycin D treatment. These results are discussed in light of a similar report concerning Atlantic salmon (Salmo salar).