Catecholamine Metabolism in Morphine Withdrawal in the Dog

Abstract

I HAVE noted¹ a decrease in the catecholamine content of the rat brain after withdrawal of chronic administration of morphine. This finding, however, seemed to be confined to a certain strain of rats with very conspicuous abstinence symptoms, while an increased urinary excretion of adrenaline and nor-adrenaline² was observed in three different rat strains. For studies of abstinence phenomena of the excitatory type, comparable with those found in man, higher species must be studied. In 1932 Tachikawa³ reported an increased amount of ‘adrenaline’ in the blood of chronically morphine-treated dogs when the drug was withheld. In 1960 and 1961 Maynert and Klingman^4,5 reported a decrease of brain and adrenal catecholamines in morphine-tolerant dogs and rabbits when an abstinence syndrome was produced by nalorphine. No numerical data were given for the decrease.