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Rojas M, Díaz P, León P, Gonzalez AA, González M, Barrientos V, Pestov NB, Alzamora R, Michea L. Mineralocorticoids modulate the expression of the β-3 subunit of the Na +, K +-ATPase in the renal collecting duct. Channels (Austin) 2017. [PMID: 28636485 DOI: 10.1080/19336950.2017.1344800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Abstract
Renal sodium reabsorption depends on the activity of the Na+,K+-ATPase α/β heterodimer. Four α (α1-4) and 3 β (β1-3) subunit isoforms have been described. It is accepted that renal tubule cells express α1/β1 dimers. Aldosterone stimulates Na+,K+-ATPase activity and may modulate α1/β1 expression. However, some studies suggest the presence of β3 in the kidney. We hypothesized that the β3 isoform of the Na+,K+-ATPase is expressed in tubular cells of the distal nephron, and modulated by mineralocorticoids. We found that β3 is highly expressed in collecting duct of rodents, and that mineralocorticoids decreased the expression of β3. Thus, we describe a novel molecular mechanism of sodium pump modulation that may contribute to the effects of mineralocorticoids on sodium reabsorption.
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Affiliation(s)
- Macarena Rojas
- a Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile , Santiago , Chile
| | - Pablo Díaz
- a Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile , Santiago , Chile
| | - Pablo León
- a Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile , Santiago , Chile
| | - Alexis A Gonzalez
- b Instituto de Química, Pontificia Universidad Católica de Valparaíso , Valparaíso , Chile
| | - Magdalena González
- a Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile , Santiago , Chile
| | - Víctor Barrientos
- a Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile , Santiago , Chile
| | - Nikolay B Pestov
- c Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry , Moscow , Russia.,d Department of Physiology and Pharmacology and Center for Diabetes and Endocrine Research , University of Toledo College of Medicine , Toledo , OH , USA
| | - Rodrigo Alzamora
- a Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile , Santiago , Chile.,e Millennium Nucleus of Ion Channels-Associated Diseases (MiNICAD) , Santiago , Chile
| | - Luis Michea
- a Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile , Santiago , Chile.,f Millennium Institute on Immunology and Immunotherapy , Santiago , Chile
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Carreño JE, Verdugo FJ, Contreras F, Montellano FA, Veloso S, Schalper KA, Sandoval M, Villanueva S, Marusic E, Irarrazabal CE. Spironolactone inhibits the activity of the Na+/H+exchanger in the aorta of mineralocorticoid-induced hypertensive rats. J Renin Angiotensin Aldosterone Syst 2015; 16:1225-31. [DOI: 10.1177/1470320315587193] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Accepted: 03/24/2015] [Indexed: 11/17/2022] Open
Affiliation(s)
- Juan E Carreño
- Laboratory of Molecular Physiology, Faculty of Medicine, Universidad de los Andes, Chile
| | - Fernando J Verdugo
- Laboratory of Molecular Physiology, Faculty of Medicine, Universidad de los Andes, Chile
| | - Felipe Contreras
- Laboratory of Molecular Physiology, Faculty of Medicine, Universidad de los Andes, Chile
| | - Felipe A Montellano
- Laboratory of Molecular Physiology, Faculty of Medicine, Universidad de los Andes, Chile
| | - Sebastian Veloso
- Laboratory of Molecular Physiology, Faculty of Medicine, Universidad de los Andes, Chile
| | | | - Mauricio Sandoval
- Laboratory of Molecular Physiology, Faculty of Medicine, Universidad de los Andes, Chile
| | - Sandra Villanueva
- Laboratory of Molecular Physiology, Faculty of Medicine, Universidad de los Andes, Chile
| | - Elisa Marusic
- Laboratory of Molecular Physiology, Faculty of Medicine, Universidad de los Andes, Chile
| | - Carlos E Irarrazabal
- Laboratory of Molecular Physiology, Faculty of Medicine, Universidad de los Andes, Chile
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Palacios J, Marusic ET, Lopez NC, Gonzalez M, Michea L. Estradiol-induced expression of N(+)-K(+)-ATPase catalytic isoforms in rat arteries: gender differences in activity mediated by nitric oxide donors. Am J Physiol Heart Circ Physiol 2004; 286:H1793-800. [PMID: 14704224 DOI: 10.1152/ajpheart.00990.2003] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
We tested the hypothesis that previously demonstrated gender differences in ACh-induced vascular relaxation could involve diverse Na(+)-K(+)-ATPase functions. We determined Na(+)-K(+)-ATPase by measuring arterial ouabain-sensitive 86Rb uptake in response to ACh. We found a significant increase of Na+ pump activity only in aortic rings from female rats (control 206 +/- 11 vs. 367 +/- 29 nmol 86Rb/K.min(-1).g wt tissue(-1); P < 0.01). Ovariectomy eliminated sex differences in Na(+)-K(+)-ATPase function, and chronic in vivo hormone replacement with 17beta-estradiol restored the ACh effect on Na(+)-K(+)-ATPase. Because ACh acts by enhancing production of NO, we examined whether the NO donor sodium nitroprusside (SNP) mimics the action of ACh on Na(+)-K(+)-ATPase activity. SNP increased ouabain-sensitive 86Rb uptake in denuded female arteries (control 123 +/- 7 vs. 197 +/- 12 nmol 86Rb/K.min(-1).g wt tissue(-1); P < 0.05). Methylene blue (an inhibitor of guanylate cyclase) and KT-5823 (a cGMP-dependent kinase inhibitor) blocked the stimulatory action of SNP. Exposure of female thoracic aorta to the Na+/K+ pump inhibitor ouabain significantly decreased SNP-induced and ACh-mediated relaxation of aortic rings. At the molecular level, Western blot analysis of arterial tissue revealed significant gender differences in the relative abundance of catalytic isoforms of Na(+)-K(+)-ATPase. Female-derived aortas exhibited a greater proportion of alpha2-isoform (44%) compared with male-derived aortas. Furthermore, estradiol upregulated the expression of alpha2 mRNA in male arterial explants. Our results demonstrate that enhancement of ACh-induced relaxation observed in female rats may be in part explained by 1) NO-dependent increased Na(+)-K(+)-ATPase activity in female vascular tissue and 2) greater abundance of Na(+)-K(+)-ATPase alpha2-isoform in females.
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Affiliation(s)
- Javier Palacios
- Laboratory of Cellular and Molecular Physiology, School of Medicine, Universidad Los Andes, Santiago, Chile 6782468
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Michea L, Irribarra V, Goecke IA, Marusic ET. Reduced Na-K pump but increased Na-K-2Cl cotransporter in aorta of streptozotocin-induced diabetic rat. Am J Physiol Heart Circ Physiol 2001; 280:H851-8. [PMID: 11158986 DOI: 10.1152/ajpheart.2001.280.2.h851] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The activities of Na-K-ATPase and Na-K-2Cl cotransporter (NKCC1) were studied in the aorta, heart, and skeletal muscle of streptozotocin (STZ)-induced diabetic rats and control rats. In the aortic rings of STZ rats, the Na-K-ATPase-dependent (86)Rb/K uptake was reduced to 60.0 +/- 5.5% of the control value (P < 0.01). However, Na-K-ATPase activity in soleus skeletal muscle fibers of STZ rats and paired control rats was similar, showing that the reduction of Na-K-ATPase activity in aortas of STZ rats is tissue specific. To functionally distinguish the contributions of ouabain-resistant (alpha(1)) and ouabain-sensitive (alpha(2) and alpha(3)) isoforms to the Na-K-ATPase activity in aortic rings, we used either a high (10(-3) M) or a low (10(-5) M) ouabain concentration during (86)Rb/K uptake. We found that the reduction in total Na-K-ATPase activity resulted from a dramatic decrement in ouabain-sensitive mediated (86)Rb/K uptake (26.0 +/- 3.9% of control, P < 0.01). Western blot analysis of membrane fractions from aortas of STZ rats demonstrated a significant reduction in protein levels of alpha(1)- and alpha(2)-catalytic isoforms (alpha(1) = 71.3 +/- 9.8% of control values, P < 0.05; alpha(2) = 44.5 +/- 11.3% of control, P < 0.01). In contrast, aortic rings from the STZ rats demonstrated an increase in NKCC1 activity (172.5 +/- 9.5%, P < 0.01); however, in heart tissue no difference in NKCC1 activity was seen between control and diabetic animals. Transport studies of endothelium-denuded or intact aortic rings demonstrated that the endothelium stimulates both Na-K-ATPase and Na-K-2Cl dependent (86)Rb/K uptake. The endothelium-dependent stimulation of Na-K-ATPase and Na-K-2Cl was not hampered by diabetes. We conclude that abnormal vascular vessel tone and function, reported in STZ-induced diabetic rats, may be related to ion transport abnormalities caused by changes in Na-K-ATPase and Na-K-2Cl activities.
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Affiliation(s)
- L Michea
- National Institutes of Health, Bethesda, Maryland 20892-1603, USA
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