[The brain catecholamines during domestication of the silver fox Vulpes fulvus]

Studies have been made on the content of catecholamines (noradrenaline and dopamine) as well as metabolites of dopamine (3,4-dihydroxyphenylacetic and homovanillic acids) in the brain structures of silver foxes which differ in their handling reactions. The level of noradrenaline was found to be significantly higher in the anterior hypothalamus of domesticated animals; no differences in noradrenaline content were found in the frontal cortex, hippocamp, posterior hypothalamus and midbrain in animals from aggressive and domesticated groups. Dopamine content was higher in the tuberculum olfactorium of domesticated animals, being lower in the striatum and n. accumbens. Metabolite level remained unaffected which is presumably due to changes in dopamine synthesis in the investigated structures. It was concluded that domestication of animals favours the specimens with an altered state of catecholaminergic system of the brain.