Premium
Uptake and metabolism of catecholamines by the human red blood cell
Author(s) -
Da Abraham,
Sapira Joseph D.
Publication year - 1972
Publication title -
clinical pharmacology and therapeutics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.941
H-Index - 188
eISSN - 1532-6535
pISSN - 0009-9236
DOI - 10.1002/cpt1972136916
Subject(s) - extracellular , intracellular , metabolite , red blood cell , chemistry , metabolism , quinidine , epinephrine , incubation , platelet , norepinephrine , red cell , blood cell , catecholamine , endocrinology , biochemistry , medicine , pharmacology , biology , dopamine
The uptake and metabolism of 14 C‐labeled norepinephrine (NE) and epinephrine (E) by the human red blood cell (RBC) was studied in platelet‐free blood in vitro. RBC incubated at 37° C. accumulated NE and E against a concentration gradient and reached an equilibrium distribution ratio, intracellular‐extracellular concentration, of about 2 at 2 hours. Uptake was temperature dependent and saturable, both phenomena characterizing an active transport system. During the incubation period, increasing concentration of metabolites, identified as the O‐methyl derivative of NE and E, respectively, appeared both in the RBC and in plasma, the concentration of the metabolite in the RBC always exceeding that in the plasma at any given point in time. Treatment with iodoacetate or quinidine resulted in increased ratios of intracellular to extracellular concentration of NE, while ethylenediaminetetraacetate decreased this ratio. Conversely, drugs known to interfere with the uptake and release of catecholamines in the adrenergiC neuron and blood platelet were without effect on the ratio of intracellular to extracellular concentration in the red cell.