Intrarenal renin-angiotensin system contributes to tubular acidification adaptation following uninephrectomy

Background/Aims: Reduction in renal mass by uninephrectomy induces a functional compensation in the remnant kidney. The activity of the angiotensin-converting enzyme (ACE) as well as renin mRNA in the proximal convoluted tubule (PCT) of uninephrectomized (UNx) rats increases. The aim of this work wa...

Descripción completa

Guardado en:

Detalles Bibliográficos
Publicado:	2001
Materias:	Angiotensin Converting enzyme Micropuncture Na+-H+ Proximal tubular acidification Renin-angiotensin system Uninephrectomy dipeptidyl carboxypeptidase losartan messenger RNA ramipril acidification adaptation animal experiment animal model animal tissue article body fluid brush border vesicle controlled study enzyme activity homeostasis kidney proximal tubule male nonhuman pH priority journal punch biopsy rat renin angiotensin aldosterone system uninephrectomy Acids Adaptation, Physiological Angiotensin-Converting Enzyme Inhibitors Animals Kidney Kidney Tubules, Proximal Losartan Male Nephrectomy Postoperative Period Ramipril Rats Rats, Wistar Receptor, Angiotensin, Type 1 Receptor, Angiotensin, Type 2 Receptors, Angiotensin Renin-Angiotensin System
Acceso en línea:	https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_10187782_v9_n1_p60_Amorena http://hdl.handle.net/20.500.12110/paper_10187782_v9_n1_p60_Amorena
Aporte de:	Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) de Universidad de Buenos Aires

id	paper:paper_10187782_v9_n1_p60_Amorena
record_format	dspace
spelling	paper:paper_10187782_v9_n1_p60_Amorena2023-06-08T15:59:53Z Intrarenal renin-angiotensin system contributes to tubular acidification adaptation following uninephrectomy Angiotensin Converting enzyme Micropuncture Na+-H+ Proximal tubular acidification Renin-angiotensin system Uninephrectomy dipeptidyl carboxypeptidase losartan messenger RNA ramipril acidification adaptation animal experiment animal model animal tissue article body fluid brush border vesicle controlled study enzyme activity homeostasis kidney proximal tubule male nonhuman pH priority journal punch biopsy rat renin angiotensin aldosterone system uninephrectomy Acids Adaptation, Physiological Angiotensin-Converting Enzyme Inhibitors Animals Kidney Kidney Tubules, Proximal Losartan Male Nephrectomy Postoperative Period Ramipril Rats Rats, Wistar Receptor, Angiotensin, Type 1 Receptor, Angiotensin, Type 2 Receptors, Angiotensin Renin-Angiotensin System Background/Aims: Reduction in renal mass by uninephrectomy induces a functional compensation in the remnant kidney. The activity of the angiotensin-converting enzyme (ACE) as well as renin mRNA in the proximal convoluted tubule (PCT) of uninephrectomized (UNx) rats increases. The aim of this work was to determine whether the increased activity of the local renin-angiotensin system (RAS) participates in the adaptation of renal function after uninephrectomy. Method: We utilized normal two-kidney (2K) and 3-week UNx rats to study the activity of the ACE in vesicles obtained from luminal membranes of proximal tubular cells and the acidification kinectics in PCTs using micropuncture techniques. Results: The converting enzyme activity was significantly larger in UNx (5.87 ± 0.69 nmol · min1 · mg protein-1) than in 2K rats (2.43 ± 0.13 nmol · min-1 · mg protein-1); p < 0.05). The acidification rate constant (κ) in PCT of 2K rats was 0.18 ± 0.02 s-1 and in UNx rats 0.30 ± 0.04 s-1 (p < 0.001). In UNx rats, microperfusion with 10-5 M ramipril or 10-5 M losartan decreased κ to 0.19 ± 0.02 and 0.18 ± 0.02 s-1, respectively, but had no effect on 2K rats. Luminal steady-state pH (pH(∞)) was the same in 2K and UNx rats, and was not modified by addition of 10-5 M ramipril or 10-5 M losartan in both groups. The proximal H+ flux (J(H+)), calculated from pH(∞) and κ, was 1.12 nmol · cm-2 · s-1 in 2K rats and, 1.77 nmol · cm-2 · s-1 in UNx rats (p < 0.001). In 2K rats, this value was not changed by 10-5 M ramipril or 10-5 M losartan, but in UNx rats J(H+) decreased 25 and 30% with ramipril or losartan, respectively (p < 0.001). Conclusions: These data suggest that the increase in the local RAS activity could be an adaptive change that contributes to maintain the homeostasis of body fluids after uninephrectomy. Copyright (C) 2000 S. Karger AG, Basel. 2001 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_10187782_v9_n1_p60_Amorena http://hdl.handle.net/20.500.12110/paper_10187782_v9_n1_p60_Amorena
institution	Universidad de Buenos Aires
institution_str	I-28
repository_str	R-134
collection	Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic	Angiotensin Converting enzyme Micropuncture Na+-H+ Proximal tubular acidification Renin-angiotensin system Uninephrectomy dipeptidyl carboxypeptidase losartan messenger RNA ramipril acidification adaptation animal experiment animal model animal tissue article body fluid brush border vesicle controlled study enzyme activity homeostasis kidney proximal tubule male nonhuman pH priority journal punch biopsy rat renin angiotensin aldosterone system uninephrectomy Acids Adaptation, Physiological Angiotensin-Converting Enzyme Inhibitors Animals Kidney Kidney Tubules, Proximal Losartan Male Nephrectomy Postoperative Period Ramipril Rats Rats, Wistar Receptor, Angiotensin, Type 1 Receptor, Angiotensin, Type 2 Receptors, Angiotensin Renin-Angiotensin System
spellingShingle	Angiotensin Converting enzyme Micropuncture Na+-H+ Proximal tubular acidification Renin-angiotensin system Uninephrectomy dipeptidyl carboxypeptidase losartan messenger RNA ramipril acidification adaptation animal experiment animal model animal tissue article body fluid brush border vesicle controlled study enzyme activity homeostasis kidney proximal tubule male nonhuman pH priority journal punch biopsy rat renin angiotensin aldosterone system uninephrectomy Acids Adaptation, Physiological Angiotensin-Converting Enzyme Inhibitors Animals Kidney Kidney Tubules, Proximal Losartan Male Nephrectomy Postoperative Period Ramipril Rats Rats, Wistar Receptor, Angiotensin, Type 1 Receptor, Angiotensin, Type 2 Receptors, Angiotensin Renin-Angiotensin System Intrarenal renin-angiotensin system contributes to tubular acidification adaptation following uninephrectomy
topic_facet	Angiotensin Converting enzyme Micropuncture Na+-H+ Proximal tubular acidification Renin-angiotensin system Uninephrectomy dipeptidyl carboxypeptidase losartan messenger RNA ramipril acidification adaptation animal experiment animal model animal tissue article body fluid brush border vesicle controlled study enzyme activity homeostasis kidney proximal tubule male nonhuman pH priority journal punch biopsy rat renin angiotensin aldosterone system uninephrectomy Acids Adaptation, Physiological Angiotensin-Converting Enzyme Inhibitors Animals Kidney Kidney Tubules, Proximal Losartan Male Nephrectomy Postoperative Period Ramipril Rats Rats, Wistar Receptor, Angiotensin, Type 1 Receptor, Angiotensin, Type 2 Receptors, Angiotensin Renin-Angiotensin System
description	Background/Aims: Reduction in renal mass by uninephrectomy induces a functional compensation in the remnant kidney. The activity of the angiotensin-converting enzyme (ACE) as well as renin mRNA in the proximal convoluted tubule (PCT) of uninephrectomized (UNx) rats increases. The aim of this work was to determine whether the increased activity of the local renin-angiotensin system (RAS) participates in the adaptation of renal function after uninephrectomy. Method: We utilized normal two-kidney (2K) and 3-week UNx rats to study the activity of the ACE in vesicles obtained from luminal membranes of proximal tubular cells and the acidification kinectics in PCTs using micropuncture techniques. Results: The converting enzyme activity was significantly larger in UNx (5.87 ± 0.69 nmol · min1 · mg protein-1) than in 2K rats (2.43 ± 0.13 nmol · min-1 · mg protein-1); p < 0.05). The acidification rate constant (κ) in PCT of 2K rats was 0.18 ± 0.02 s-1 and in UNx rats 0.30 ± 0.04 s-1 (p < 0.001). In UNx rats, microperfusion with 10-5 M ramipril or 10-5 M losartan decreased κ to 0.19 ± 0.02 and 0.18 ± 0.02 s-1, respectively, but had no effect on 2K rats. Luminal steady-state pH (pH(∞)) was the same in 2K and UNx rats, and was not modified by addition of 10-5 M ramipril or 10-5 M losartan in both groups. The proximal H+ flux (J(H+)), calculated from pH(∞) and κ, was 1.12 nmol · cm-2 · s-1 in 2K rats and, 1.77 nmol · cm-2 · s-1 in UNx rats (p < 0.001). In 2K rats, this value was not changed by 10-5 M ramipril or 10-5 M losartan, but in UNx rats J(H+) decreased 25 and 30% with ramipril or losartan, respectively (p < 0.001). Conclusions: These data suggest that the increase in the local RAS activity could be an adaptive change that contributes to maintain the homeostasis of body fluids after uninephrectomy. Copyright (C) 2000 S. Karger AG, Basel.
title	Intrarenal renin-angiotensin system contributes to tubular acidification adaptation following uninephrectomy
title_short	Intrarenal renin-angiotensin system contributes to tubular acidification adaptation following uninephrectomy
title_full	Intrarenal renin-angiotensin system contributes to tubular acidification adaptation following uninephrectomy
title_fullStr	Intrarenal renin-angiotensin system contributes to tubular acidification adaptation following uninephrectomy
title_full_unstemmed	Intrarenal renin-angiotensin system contributes to tubular acidification adaptation following uninephrectomy
title_sort	intrarenal renin-angiotensin system contributes to tubular acidification adaptation following uninephrectomy
publishDate	2001
url	https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_10187782_v9_n1_p60_Amorena http://hdl.handle.net/20.500.12110/paper_10187782_v9_n1_p60_Amorena
_version_	1768545609823813632

Intrarenal renin-angiotensin system contributes to tubular acidification adaptation following uninephrectomy

Ejemplares similares