Summary
Initial rates of the extraneuronal uptake of 3H-(−)-adrenaline of very high specific activity were determined in the perfused rat heart, fluorimetrically for unlabelled and by scintillation counting for labelled amine. The presence of nearly four tritium substituents in the adrenaline molecule slowed uptake by a factor of 5.56. The isotope effect of tritium apears to increase in direct proportion to the number of tritium substituents per molecule. It is concluded that 3H-catecholamines of very high specific activity are unsuitable for studies of the uptake and metabolism of 3H-catecholamines.
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References
Iversen LL (1965) The uptake of catechol amines at high perfusion concentrations in the rat isolated heart: a novel catechol amine uptake process. Br J Pharmacol 25:18–33
Trendelenburg U (1980) A kinetic analysis of the extraneuronal uptake and metabolism of catecholamines. Rey Physiol Biochem Pharmacol 87:33–115
Trendelenburg U, Stefano FJE, Grohmann M (1983) The isotope effect of tritium in 3H-noradrenaline. Naunyn-Schmiedeberg's Arch Pharmacol 323:128–140
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This study was supported by the Deutsche Forschungsgemeinschaft (Tr. 96)
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Grohmann, M., Trendelenburg, U. The isotope effect of tritium in 3H-(−)-adrenaline with very high specific activity. Naunyn-Schmiedeberg's Arch. Pharmacol. 324, 233–234 (1983). https://doi.org/10.1007/BF00503901
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DOI: https://doi.org/10.1007/BF00503901