Copper Intoxication in Chinook Salmon (Oncorhynchus tshawytscha) Induced by Natural Springwater: Effects on Gill Na+, K+-ATPase, Hematocrit, and Plasma Glucose

Abstract

Chinook salmon (Oncorhynchus tshawytscha) parr and smolts were exposed to natural springwater with an elevated copper concentration. Gill Na+, K+-ATPase activity in parr was unaffected by 18 h of exposure, while significant inhibition was found in smolts. Under the same exposure conditions, significant increases in hematocrit and plasma glucose were found in both parr and smolts. The results suggest that only the Na+, K+-ATPase enzyme associated with chloride cells in the gill of smolts is susceptible to inhibition by copper, thus explaining the lack of enzyme inhibition found in parr.