The influence of the density of adrenergic innervation on the extracellular steady-state concentration gradient for 3H-noradrenaline.

After inhibition of extraneuronal uptake by corticosterone, isolated right atria and lengthwise halved vasa deferentia of the rat were incubated with 0.2 μmol/l 3H-noradrenaline for 60 min, washed out for 100 min and then prepared for autoradiography. The autoradiographic images were digitized, and silver grain density was determined as a function of the distance from the surface.