The influence of cocaine on the metabolism of adrenaline in vivo and on the storage and release of catecholamines in isolated chromaffin granules.

The metabolism of adrenaline-8-"4C was studied in rats treated with cocaine. The cocaine was administered either as a single subcutaneous injection sf 50 mg/kg or by subcutaneous injection of 50 rngikg of cocaine on 12 consecutive days. In both leases the pattern of urinary metabolites is similar to the pattern observed for controis. Incubation of rat or ox adrenal medullary granules in the presence of 10-4 and 10-2 M cocaine brings abut a release of catecholamines without producing a release of adenosine triphosphate or of proteins. A lower concentration of cocaine, 104 M, is without effect on the granules. This dose of cocaine is also without effect on the uptake sf adrenalirae+-l4C by ox chromaffin granules.