Responses of plasma glucose, free fatty acids and glucagon to cobalt and nickel chlorides by Gallus domesticus

1. 1. Hyperglycaemia developed inconsistently following treatment of the fed or starved fowl with cobalt chloride. The concentration of plasma free fatty acids (FFA) increased in fed birds but fell in starved birds. 2. 2. Cobalt chloride caused a significant increase in glucagon-like immunoreactive plasma only in the fully fed bird. 3. 3. Nickel chloride stimulated hyperglycaemia which was transient in fed birds but prolonged in starved birds. There was a concomitant fall in the plasma FFA of the former, and no change in the latter. 4. 4. It is concluded that the efficacy of cobalt and nickel in stimulating the release of pancreatic glucagon is doubtful.