Uptake of Catecholamines by a Particulate Fraction of the Adrenal Medulla

Science  12 Jan 1962:
Vol. 135, Issue 3498, pp. 107-108
DOI: 10.1126/science.135.3498.107


Chromaffin granules isolated from beef adrenal medulla took up C14-labeled catecholamines from an isotonic medium at 37°C at a rate approximately 20 times the rate at 0°C. The uptake was stimulated three- to five-fold by Mg++ and adenosine triphosphate. Reserpine (1 x 10-5M) caused a 90 percent inhibition of uptake; ethylenediaminetetraacetic acid completely inhibited the stimulation by magnesium and adenosine triphosphate, and the inhibition could be reversed by addition of excess Mg++.