Free cyanide-induced biochemical changes in nitrogen metabolism of the Indian major carp Cirrhinus mrigala.

We studied the effect of free cyanide on several aspects of nitrogen metabolism in the gills, liver, and muscle tissue of the Indian major carp, Cirrhinus mrigala. Free amino acid levels and protease activity were elevated following exposure to lethal and sublethal doses of free cyanide. At the lethal concentration, significant changes were noticed on day 4 for both parameters. The normal condition was restored only at the sublethal concentration.