EFFECTS OF MAO-A AND MAO-B SELECTIVE INHIBITORS RO-41-1049 AND RO-19-6327 ON THE DEAMINATION OF NEWLY FORMED DOPAMINE IN THE RAT-KIDNEY

• Type: Article in International Scientific Journal
• Date: 1990

Authors

Fernandes MH (Author) FMDUP; soares-da-silva, p (Author) FMUP

Journal

Title: Journal of Pharmacology and Experimental Therapeutics

Vol. 255

Pages: 1309-1313

ISSN: 0022-3565

Publisher: American Society for Pharmacology and Experimental Therapeutics

Indexing

ISI Web of Knowledge - 35 Citations

Scopus - 33 Citations

Other information

Authenticus ID: P-001-RC0

Abstract (EN): 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 (DA) in kidney slices incubated with exogenous L-3,4-dihydroxyphenylalanine (L-dopa; 1-100-mu-M). Ro 41-1049 (50, 100 and 250 nM) was found to produce a concentration-dependent increase of newly formed DA (36-56% increase) and reduced 3,4-dihydroxyphenylacetic (DOPAC) formation (45-86% reduction). Ro 19-6327 (50, 100 and 250 nM) was found not to affect the accumulation of newly formed DA up to 50-mu-M L-dopa in the medium, but significantly reduced the formation of DOPAC. At the concentration of 100-mu-M L-dopa, Ro 19-6327 (100 and 250 nM) significantly increased (by 32 and 132%, respectively) the DA tissue levels in kidney slices. Ro 19-6327 (100 and 250 nM) was found to decrease (30-70% reduction) DOPAC formation; this effect was also observed when tissues were incubated with L-dopa at concentrations lower than 50-mu-M. It is concluded that both MAO-A and MAO-B are important in the metabolism of newly formed DA in kidney slices incubated with exogenous L-dopa. The results also suggest that there at least two compartments in which newly formed DA can be deaminated.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 5