Neuronal and extraneuronal uptake of L-3H-adrenaline and L-14C-noradrenaline in the fish spleen.
The neuronal and extraneuronal uptake of adrenaline and noradrenaline in the isolated perfused spleen of the cod has been studied using radiolabelled amines. The neuronal uptake of adrenaline shows an optimum at 0.5 microgram/ml, but is less efficient than for noradrenaline in the concentration range 0.01-2.5 micrograms/ml. The neuronal uptake of noradrenaline accounts for 60-70% of the total (neuronal plus extraneuronal) uptake in the concentration range 0.01-1.0 microgram/ml. At higher concentrations (2.5-5.0 micrograms/ml) the importance of the extraneuronal uptake increases for both amines, to reach more than 90% of the total uptake at 5.0 micrograms/ml. The extraneuronal uptake shows equal efficiency for the two amines throughout the concentration range studied. It is concluded that the cod spleen possesses a neuronal uptake mechanism which shows a higher uptake efficiency for noradrenaline than for adrenaline, while the extraneuronal uptake mechanism shows no preference.
D000818:Animals; D003714:Denervation; D004837:Epinephrine / Q000378:metabolism*; D005399:Fishes; D009474:Neurons / Q000378:metabolism*; D009638:Norepinephrine / Q000378:metabolism*; D010477:Perfusion; D013154:Spleen / Q000294:innervation / Q000378:metabolism*
D009638:Norepinephrine; D004837:Epinephrine