Metabolism of radiocopper (Cu⁶⁴) in the rat

¹ Section of Biochemistry, Mayo Clinic and Mayo Foundation, Rochester, Minnesota

About 100 µg of copper as cupric acetate-Cu⁶⁴ was given iv to adult, male rats. Maximal concentrations of Cu⁶⁴ were reached quickly in the excretory organs—liver, kidney, and gastrointestinal tract—which then slowly released their radioactivity. In most of the other organs a progressive accumulation of Cu⁶⁴ began after the disappearance of most of the nonceruloplasminic Cu⁶⁴ from the plasma and after ceruloplasmin-Cu⁶⁴ emerged in the plasma, suggesting that ceruloplasmin may be the copper donor for the tissues. The disappearance of plasmatic Cu⁶⁴ tended to parallel that from the liver after the first 48 hr.

Key Words: radiocopper in rat organs • copper metabolism in rat • ceruloplasmin

Submitted on February 4, 1965