title: Regulation of Dopamine Uptake by Vasoactive Peptides in the Kidney.
abstract: Considering the key role of renal dopamine in tubular sodium handling, we hypothesized that c-type natriuretic peptide (CNP) and Ang-(1-7) may regulate renal dopamine availability in tubular cells, contributing to Na(+), K(+)-ATPase inhibition. Present results show that CNP did not affect either (3)H-dopamine uptake in renal tissue or Na(+), K(+)-ATPase activity; meanwhile, Ang-(1-7) was able to increase (3)H-dopamine uptake and decreased Na(+), K(+)-ATPase activity in renal cortex. Ang-(1-7) and dopamine together decreased further Na(+), K(+)-ATPase activity showing an additive effect on the sodium pump. In addition, hydrocortisone reversed Ang-(1-7)-dopamine overinhibition on the enzyme, suggesting that this inhibition is closely related to Ang-(1-7) stimulation on renal dopamine uptake. Both anantin and cANP (4-23-amide) did not modify CNP effects on (3)H-dopamine uptake by tubular cells. The Mas receptor antagonist, A-779, blocked the increase elicited by Ang-(1-7) on (3)H-dopamine uptake. The stimulatory uptake induced by Ang-(1-7) was even more pronounced in the presence of losartan, suggesting an inhibitory effect of Ang-(1-7) on AT1 receptors on (3)H-dopamine uptake. By increasing dopamine bioavailability in tubular cells, Ang-(1-7) enhances Na(+), K(+)-ATPase activity inhibition, contributing to its natriuretic and diuretic effects.
authors.affiliation: Instituto de Investigaciones Cardiológicas ININCA, UBA-CONICET, Facultad de Farmacia y Bioquímica, UBA, Buenos Aires, Argentina.
authors.forename: N L
authors.identifier: 0000-0002-5199-1129
authors.initials: NL
authors.lastname: Rukavina Mikusic
authors.affiliation: Instituto de Investigaciones Cardiológicas ININCA, UBA-CONICET, Facultad de Farmacia y Bioquímica, UBA, Buenos Aires, Argentina.
authors.forename: N M
authors.identifier: 0000-0002-1272-0457
authors.initials: NM
authors.lastname: Kouyoumdzian
authors.affiliation: Instituto de Investigaciones Cardiológicas ININCA, UBA-CONICET, Facultad de Farmacia y Bioquímica, UBA, Buenos Aires, Argentina; Cátedras de Anatomía e Histología, Facultad de Farmacia y Bioquímica, UBA, Buenos Aires, Argentina.
authors.forename: E
authors.identifier: 0000-0002-3541-900X
authors.initials: E
authors.lastname: Rouvier
authors.affiliation: Cátedras de Química Biológica, Facultad de Farmacia y Bioquímica, UBA, Buenos Aires, Argentina.
authors.forename: M M
authors.initials: MM
authors.lastname: Gironacci
authors.affiliation: Instituto de Investigaciones Cardiológicas ININCA, UBA-CONICET, Facultad de Farmacia y Bioquímica, UBA, Buenos Aires, Argentina; Laboratorio de Medicina Experimental, Hospital Alemán, Buenos Aires, Argentina.
authors.forename: J E
authors.identifier: 0000-0003-4401-6824
authors.initials: JE
authors.lastname: Toblli
authors.affiliation: Instituto de Investigaciones Cardiológicas ININCA, UBA-CONICET, Facultad de Farmacia y Bioquímica, UBA, Buenos Aires, Argentina.
authors.forename: B E
authors.identifier: 0000-0002-5672-1996
authors.initials: BE
authors.lastname: Fernández
authors.affiliation: Instituto de Investigaciones Cardiológicas ININCA, UBA-CONICET, Facultad de Farmacia y Bioquímica, UBA, Buenos Aires, Argentina; Cátedras de Anatomía e Histología, Facultad de Farmacia y Bioquímica, UBA, Buenos Aires, Argentina.
authors.forename: M R
authors.identifier: 0000-0003-2909-8534
authors.initials: MR
authors.lastname: Choi