Journal article
Ontogeny of DA1 receptor-mediated natriuresis in the rat: in vivo and in vitro correlations
American journal of physiology. Regulatory, integrative and comparative physiology, Vol.263(3), pp.R631-R638
09/1992
DOI: 10.1152/ajpregu.1992.263.3.R631
PMID: 1357983
Abstract
The natriuretic and diuretic effects of dopamine are attenuated in the young. Because dopamine has actions on receptors (e.g., adrenergic, serotonin) other than dopamine, we studied a novel dopamine agonist, pramipexole, which has a selectivity to both DA1 and DA2-receptor subtypes. Intravenous administration of pramipexole resulted in a dose-related (1, 10, and 100 micrograms.kg-1.min-1) increase in urine flow and absolute and fractional sodium excretion and a decrease in mean arterial pressure (MAP) in three groups of rats studied. Pramipexole induced a greater decrease in MAP in 6- to 7- (n = 5) and 9- to 16- (n = 6) than in 3- to 4-wk-old (n = 8) rats; the natriuresis and diuresis were greatest in 12- to 16- and least in 3- to 4-wk-old rats. The renal effects of pramipexole were mainly due to actions at the DA1 receptor, since these effects were completely blocked by the coinfusion of a DA1 antagonist, SKF 83742. To explore further a cause of the attenuated natriuretic effect of pramipexole in the young, we studied the effect of a selective DA1-receptor agonist, fenoldopam, on amiloride-sensitive 22Na+ uptake in renal brush-border membrane vesicles. The 3-s amiloride-sensitive uptake was inhibited (45%) by fenoldopam (5 x 10(-5)M) in 9- to 16- (n = 6) but not in 3- to 4-wk-old (n = 5) rats. These studies suggest that the attenuated natriuretic effect of dopamine in the young is in part due to decreased DA1 action on the brush-border membrane Na(+)-H+ exchanger.
Details
- Title: Subtitle
- Ontogeny of DA1 receptor-mediated natriuresis in the rat: in vivo and in vitro correlations
- Creators
- Shinya Kaneko - Kurume UniversityFred AlbrechtLaureano D AsicoGilbert M EisnerJean E RobillardPedro A Jose
- Resource Type
- Journal article
- Publication Details
- American journal of physiology. Regulatory, integrative and comparative physiology, Vol.263(3), pp.R631-R638
- Publisher
- AMER PHYSIOLOGICAL SOC; BETHESDA
- DOI
- 10.1152/ajpregu.1992.263.3.R631
- PMID
- 1357983
- ISSN
- 0363-6119
- eISSN
- 1522-1490
- Grant note
- NHLBI NIH HHS: HL-23081
- Language
- English
- Date published
- 09/1992
- Academic Unit
- Molecular Physiology and Biophysics; Nephrology, Dialysis and Transplantation; Stead Family Department of Pediatrics; Medicine Administration
- Record Identifier
- 9984774210802771
Metrics
3 Record Views