Abstract
Summary The method byNagatsu andUdenfriend (1972) to measure dopamine-β-hydroxylase (DBH) activity was applied for tissue samples. Proximal to a crush or a ligature of the perihilar tissue of the rat salivary glands, DBH activity was found to increase about linearly with time. However, more DBH activity accumulated after ligation than after crushing. Noradrenaline (NA) accumulated also after a ligature but the increase appeared to exceed a linear one. The same pattern for the increase in NA we earlier had observed proximal to a crush of the rat sciatic nerve. It was now found that the accumulation of DBH activity was about linear with time in the crushed sciatic nerve, without any signs of supra-normal increase. The same increase was found after a crush as after a ligature. The ratio of accumulating NA and DBH activity agreed in the two neuronal systems.