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Role of monoamine oxidase A and B in the deamination of newly-formed dopamine in the rat kidney

  • M. Helena Fernandes
  • P. Soares-da-Silva
Part of the Journal of Neural Transmission book series (NEURAL SUPPL, volume 32)

Summary

The present study has examined the effects of two selective inhibitors of monoamine oxidase (MAO) type A and B, respectively Ro 41-1049 and Ro 19-6327, on the deamination of newly-synthesized dopamine in kidney slices incubated with exogenous L-DOPA (50 and 100μmol/1). Ro 41-1049 (50, 100 and 250 nmol/l) was found to produce a concentration-dependent increase of newly-formed dopamine (36–56% increase) and reduced DOPAC formation (45–86% reduction). Ro 19-6327 (50, 100 and 250 nmol/1), was found not to affect the accumulation of newly-formed dopamine at 50μmol/1 L-DOPA in the medium, but significantly reduced the formation of DOPAC. At the concentration of 100 μmol/1 of L-DOPA, Ro 19-6327 (100 and 250 nmol/1) significantly increased (by 32% and 132%, respectively), the dopamine tissue levels in kidney slices and decreased DOPAC formation. It is concluded that both MAO-A and MAO-B are important in the metabolism of newly-formed dopamine in kidney slices incubated with exogenous L-DOPA.

Keywords

Monoamine Oxidase Atrial Natriuretic Peptide Tubular Epithelial Cell Krebs Solution Copper Sulphate 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

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Copyright information

© Springer-Verlag 1990

Authors and Affiliations

  • M. Helena Fernandes
    • 1
  • P. Soares-da-Silva
    • 1
  1. 1.Laboratório de FarmacologiaFacul-dade de MedicinaPortoPortugal

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