High sodium intake increases the urinary excretion of L-3,4-dihydroxyphenylalanine but fails to alter the urinary excretion of dopamine and amine metabolites in Wistar rats

• Type: Article in International Scientific Journal
• Date: 1996

Authors

vieira-coelho, ma (Author) Other; Pestana M (Author) FMUP; soares-da-silva, p (Author) FMUP

Journal

The Journal is awaiting validation by the Administrative Services.

Title: GENERAL PHARMACOLOGY

Vol. 27

Pages: 1421-1427

ISSN: 0306-3623

Indexing

ISI Web of Knowledge - 8 Citations

Scopus - 10 Citations

Other information

Authenticus ID: P-001-D9N

DOI: 10.1016/s0306-3623(96)00064-x

Abstract (EN): 1. The present study has examined the daily urinary excretion of L-DOPA, dopamine and its metabolites (DOPAC, 3-MT and HVA) during normal salt (NS) and high salt (HS) diets. 2. Daily urinary excretion of L-DOPA, DA, DOPAC, 3-MT and HVA during the 4-day period of NS diet averaged, respectively, 7.6+/-0.4, 71+/-5, 217+/-22, 570+/-90 and 1217+/-110 nmol/kg/day. The slight increase in the urinary excretion of DA, DOPAC and 3-MT (16% to 42% increase), when rats were fed a HS diet, did not achieve statistical significance. 3. In contrast, the urinary levels of L-DOPA during the HS diet period (11+/-1 nmol/kg/day) were found to be significantly higher than during the NS diet period; the maximal increase in the urinary excretion of L-DOPA (93% increase) was observed in the first day and then a progressive decline was observed towards the end of the HS intake period. 4. During the first 5 days of the HS intake period, the urine output of noradrenaline (NA) was found to increase (27% to 83%) and then to progressively decline to baseline values (13.5+/-0.7 nmol/kg/day). 5. Urinary excretion of adrenaline (AD) during the HS intake period was found to increase (72% to 146%); the mean daily urinary excretion of AD during the NS diet period averaged 2.5+/-0.4 nmol/kg/day. NA and DA contents in the kidney of rats on a NS diet were not significantly different from that of rats in a HS diet. 6. It is concluded that long-term HS intake in Wistar rats fails to change the urinary excretion of DA and of its metabolites (DOPAC, 3-MT and HVA). Furthermore, the discrepant profile in the urinary excretion of L-DOPA and DA during HS intake might be related to a reduction in the tubular uptake of the amino acid, rather than reflecting a decrease in its decarboxylation. Copyright (C) 1996 Elsevier Science Inc.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 7