title: Concerted regulation of renal plasma flow and glomerular filtration rate by renal dopamine and NOS I in rats on high salt intake.
abstract: Under high sodium intake renal dopamine (DA) increases while NOS I expression in macula densa cells (MD) decreases. To explore whether renal DA and NOS I, linked to natriuresis and to the stability of the tubuloglomerular feedback, respectively, act in concert to regulate renal plasma flow (RPF) and glomerular filtration rate (GFR). Male Wistar rats were studied under a normal sodium intake (NS, NaCl 0.24%) or a high sodium intake (HS, NaCl 1% in drinking water) during the 5 days of the study. For the last two days, the specific D1-like receptor antagonist SCH 23390 (1 mg kg bwt-1day-1, sc) or a vehicle was administered. HS intake increased natriuresis, diuresis, and urinary DA while it decreased cortical NOS I expression (P< 0.05 vs. NS), Nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) activity in MD (P< 0.001 vs. NS) and cortical nitrates+nitrites (NOx) production (NS 2.04 ± 0.22 vs. HS 1.28 ± 0.10 nmol mg protein-1,P< 0.01). Treatment with SCH 23390 to rats on HS sharply decreased hydroelectrolyte excretion (P< 0.001 vs. HS) while NOS I expression, NADPH-d activity and NOx production increased (P< 0.05 vs. HS for NOS I andP< 0.001 vs. HS for NADPH-d and NOx). SCH 23390 increased RPF and GFR in HS rats (P< 0.01 HS+SCH vs. HS). It did not cause variations in NS rats. Results indicate that when NS intake is shifted to a prolonged high sodium intake, renal DA through the D1R, and NOS I in MD cells act in concert to regulate RPF and GFR to stabilize the delivery of NaCl to the distal nephron.
authors.affiliation: Laboratorio de Neuropatología Experimental, Instituto de Biología Celular y Neurociencia "Prof. E. De Robertis" (IBCN), Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina.
authors.forename: Mariano E
authors.initials: ME
authors.lastname: Ibarra
authors.affiliation: Cátedra de Biología Celular y Molecular, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina.
authors.forename: Maria F
authors.initials: MF
authors.lastname: Albertoni Borghese
authors.affiliation: Cátedra de Biología Celular y Molecular, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina.
authors.forename: Mónica P
authors.initials: MP
authors.lastname: Majowicz
authors.affiliation: Cátedra de Biología Celular y Molecular, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina.
authors.forename: María C
authors.initials: MC
authors.lastname: Ortiz
authors.affiliation: Laboratorio de Neuropatología Experimental, Instituto de Biología Celular y Neurociencia "Prof. E. De Robertis" (IBCN), Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina.
authors.forename: Fabián
authors.initials: F
authors.lastname: Loidl
authors.affiliation: Laboratorio de Neuropatología Experimental, Instituto de Biología Celular y Neurociencia "Prof. E. De Robertis" (IBCN), Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina.
authors.forename: Manuel
authors.initials: M
authors.lastname: Rey-Funes
authors.affiliation: Laboratorio de Riñón, Instituto de Investigaciones Médicas A. Lanari Universidad de Buenos Aires, Buenos Aires, Argentina.
authors.forename: Luis A
authors.initials: LA
authors.lastname: Di Ciano
authors.affiliation: Laboratorio de Riñón, Instituto de Investigaciones Médicas A. Lanari Universidad de Buenos Aires, Buenos Aires, Argentina ibarraf@hotmail.com.|Departamento de Ciencias Fisiológicas, Facultad de Medicina Universidad de Buenos Aires, Buenos Aires, Argentina.
authors.forename: Fernando R
authors.initials: FR
authors.lastname: Ibarra
mesh_terms: D000818:Animals; D001552:Benzazepines / Q000494:pharmacology; D001794:Blood Pressure / Q000187:drug effects; D004298:Dopamine / Q000378:metabolism; D018492:Dopamine Antagonists / Q000494:pharmacology; D005919:Glomerular Filtration Rate / Q000187:drug effects / Q000502:physiology*; D007672:Kidney Cortex / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D009249:NADP / Q000378:metabolism; D009318:Natriuresis / Q000187:drug effects / Q000502:physiology; D052248:Nitric Oxide Synthase Type I / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D017595:Renal Plasma Flow / Q000187:drug effects / Q000502:physiology*; D012965:Sodium Chloride / Q000378:metabolism*; D012982:Sodium, Dietary
chemical_list: D001552:Benzazepines; D018492:Dopamine Antagonists; C534628:SCH 23390; D012982:Sodium, Dietary; D012965:Sodium Chloride; D009249:NADP; D052248:Nitric Oxide Synthase Type I; C496322:Nos1 protein, rat; D004298:Dopamine
keywords: High salt intake; NOS I in MD; Regulation of Renal Plasma Flow; Renal Dopamine