Noradrenaline Release from Isolated Nerve Granules

E uler U. S. V. and F. L ishajko . Noradrenaline release from isolated nerve granules. Some properties of isolated transmitter granules obtained by high g centrifugation of press juice from bovine splenic nerves have been studied. Of the total noradrenaline present in the press juice 20–35 per cent was recovered in the sediment. The granules are stable for several hours at + 4° C but rapidly lose their noradrenaline on incubation in isotonic neutral media at 37° C. Noradrenaline is rapidly released even at low temperature at pH 4 and below, and by detergents. Hypo‐ and hyperosmotic solutions and freezing and thawing, had a moderate releasing effect. Acetylcholine, nicotine, serotonin and GABA had no detectable effect on the noradrenaline release from the granules. Nerve granules are more sensitive to temperature than adrenal medullary granules but show higher resistance to freezing and thawing and osmotic changes.