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Xu L, Hu G, Qiu J, Fan Y, Ma Y, Miura T, Kohzuki M, Ito O. High Fructose-Induced Hypertension and Renal Damage Are Exaggerated in Dahl Salt-Sensitive Rats via Renal Renin-Angiotensin System Activation. J Am Heart Assoc 2021; 10:e016543. [PMID: 34259014 PMCID: PMC8483472 DOI: 10.1161/jaha.120.016543] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background High‐fructose diet (HFr) induces hypertension and renal damage. However, it has been unknown whether the HFr‐induced hypertension and renal damage are exaggerated in subjects with salt sensitivity. We tested impacts of HFr in Dahl salt‐sensitive (DS) and salt‐resistant (DR) rats. Methods and Results Male DS and DR rats were fed control diet or HFr (60% fructose) with normal‐salt content. After 12 weeks, plasma and urinary parameters, renal histological characteristics, and renal expression of renin‐angiotensin system components were examined. Furthermore, effects of renin‐angiotensin system inhibitors were also examined in DS rats fed the HFr. HFr elevated blood pressure in DS rats but not in DR rats. HFr increased urinary albumin and liver type fatty acid binding protein excretions in both rats, but the excretions were exaggerated in DS rats. HFr increased plasma lipids and uric acid in both rats, whereas HFr increased creatinine clearance in DS rats but not DR rats. Although HFr decreased plasma renin activity in DS rats, HFr‐induced glomerular injury, afferent arteriolar thickening, and renal interstitial fibrosis were exaggerated in DS rats. HFr increased renal expression of angiotensinogen, renin, (pro)renin receptor, angiotensin‐converting enzyme, and angiotensin II type 1 receptor in DS rat, whereas HFr increased only angiotensin‐converting enzyme expression and decreased renin and angiotensin II type 1 receptor expressions in DR rats. Enalapril and candesartan attenuated the HFr‐induced hypertension, albuminuria, glomerular hyperfiltration, and renal damage in DS rats. Conclusion HFr‐induced hypertension and renal damage are exaggerated in DS rats via renal renin‐angiotensin system activation, which can be controlled by renin‐angiotensin system inhibitors.
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Affiliation(s)
- Lusi Xu
- Department of Internal Medicine and Rehabilitation Science Tohoku University Graduate School of Medicine Sendai Japan
| | - Gaizun Hu
- Department of Pharmacology and Toxicology School of Medicine Virginia Commonwealth University Richmond VA
| | - Jiahe Qiu
- Department of Internal Medicine and Rehabilitation Science Tohoku University Graduate School of Medicine Sendai Japan
| | - Yuxuan Fan
- Department of Internal Medicine and Rehabilitation Science Tohoku University Graduate School of Medicine Sendai Japan
| | - Yixuan Ma
- Department of Internal Medicine and Rehabilitation Science Tohoku University Graduate School of Medicine Sendai Japan
| | - Takahiro Miura
- Department of Internal Medicine and Rehabilitation Science Tohoku University Graduate School of Medicine Sendai Japan
| | - Masahiro Kohzuki
- Department of Internal Medicine and Rehabilitation Science Tohoku University Graduate School of Medicine Sendai Japan
| | - Osamu Ito
- Department of Internal Medicine and Rehabilitation Science Tohoku University Graduate School of Medicine Sendai Japan.,Division of General Medicine and Rehabilitation Tohoku Medical and Pharmaceutical University Faculty of Medicine Sendai Japan
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Loria AS, Pollock DM, Pollock JS. Angiotensin II is required to induce exaggerated salt sensitivity in Dahl rats exposed to maternal separation. Physiol Rep 2015; 3:3/5/e12408. [PMID: 25999404 PMCID: PMC4463836 DOI: 10.14814/phy2.12408] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
We previously reported that maternal separation, rat model of early life stress, enhances pressor responses to acute and chronic stressors. The aims of this study were to determine whether Dahl salt-sensitive (DS) rats subjected to maternal separation (MatSep-DS) as compared to normally reared DS (Ctl-DS) rats show exaggerated blood pressure responses to acute behavioral stressors, such as restraint stress or air jet stress (AJS), or, hypertensive stimuli including chronic high-salt diet (4% NaCl) and angiotensin II (AngII) infusion (200 ng/Kg/min) during 1 week. MatSep was performed in male DS rats for 3 h/day from postnatal days 2-14. At 8 weeks of age, rats were implanted with telemetry transmitters and allowed to recover. Mean arterial pressure (MAP) was not different between MatSep-DS and Ctl-DS rats at baseline (120 ± 2 mmHg vs. 118 ± 1 mmHg, n = 4-8). Blood pressure responses during AJS and restraint stress were not different between MatSep-DS and Ctl-DS at 3 min. However, blood pressure recovery from AJS was significantly impaired in MatSep-DS rats compared to Ctl-DS rats (P < 0.05). 3-h stress-induced similar responses in MatSep and Ctl-DS rats. Chronic blood pressure responses to AngII infusion in rats fed a high-salt diet displayed enhanced MAP in MatSep-DS when compared with Ctl-DS rats (167 ± 5 mmHg vs. 152 ± 2 mmHg, pinteraction <0.05). However, MAP increased similarly in both groups in response to AngII infusion or high-salt diet separately. Renal parameters such as proteinuria, urine flow rate, and urine electrolytes were not different between groups in response to each treatment. In summary, salt sensitivity induces exaggerated blood pressor responses only in presence of AngII due to early life stress.
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Affiliation(s)
- Analia S Loria
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, Kentucky Department of Medicine, Georgia Regents University, Augusta, Georgia
| | - David M Pollock
- Department of Medicine, Georgia Regents University, Augusta, Georgia Cardio-Renal Physiology & Medicine, Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama
| | - Jennifer S Pollock
- Department of Medicine, Georgia Regents University, Augusta, Georgia Cardio-Renal Physiology & Medicine, Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama
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3
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Flister MJ, Hoffman MJ, Reddy P, Jacob HJ, Moreno C. Congenic mapping and sequence analysis of the Renin locus. Hypertension 2013; 61:850-6. [PMID: 23460292 DOI: 10.1161/hypertensionaha.111.01008] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Renin was the first blood pressure (BP) quantitative trait locus mapped by linkage analysis in the rat. Subsequent BP linkage and congenic studies capturing different portions of the renin region have returned conflicting results, suggesting that multiple interdependent BP loci may be residing in the chromosome 13 BP quantitative trait locus that includes Renin. We used SS-13(BN) congenic strains to map 2 BP loci in the Renin region (chr13: 45.2-49.0 Mb). We identified a 1.1-Mb protective Brown Norway region around Renin (chr13: 46.1-47.2 Mb) that significantly decreased BP by 32 mm Hg. The Renin protective BP locus was offset by an adjacent hypertensive locus (chr13: 47.2-49.0 Mb) that significantly increased BP by 29 mm Hg. Sequence analysis of the protective and hypertensive BP loci revealed 1433 and 2063 variants between Dahl salt-sensitive/Mcwi and Brown Norway rats, respectively. To further reduce the list of candidate variants, we regenotyped an overlapping SS-13(SR) congenic strain (S/renrr) with a previously reported BP phenotype. Sequence comparison among Dahl salt-sensitive, Dahl R, and Brown Norway reduced the number of candidate variants in the 2 BP loci by 42% for further study. Combined with previous studies, these data suggest that at least 4 BP loci reside within the 30-cM chromosome 13 BP quantitative trait locus that includes Renin.
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Affiliation(s)
- Michael J Flister
- Human and Molecular Genetics Center, Medical College of Wisconsin, Milwaukee, WI 53226, USA
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4
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Liang B, Leenen FHH. Prevention of salt induced hypertension and fibrosis by angiotensin converting enzyme inhibitors in Dahl S rats. Br J Pharmacol 2007; 152:903-14. [PMID: 17906684 PMCID: PMC2078219 DOI: 10.1038/sj.bjp.0707472] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND AND PURPOSE In Dahl S rats, high salt increases activity of the tissue renin-angiotensin-aldosterone system (RAAS) in the CNS, heart and kidneys. Here, we assessed the effects of chronic angiotensin converting enzyme (ACE) inhibition on salt-induced hypertension and cardiovascular and renal hypertrophy and fibrosis, relative to the extent of ACE blockade. EXPERIMENTAL APPROACH From 4.5 weeks of age, Dahl S rats received either the lipophilic ACE inhibitor trandolapril (1 or 5 mg kg(-1) day(-1)) or the hydrophilic ACE inhibitor lisinopril (10 or 50 mg kg(-1) day(-1)) and a high salt diet was started 0.5 week later. Treatments ended at 9 weeks of age. KEY RESULTS High salt diet markedly increased blood pressure (BP), decreased plasma angiotensin II and increased ACE binding densities in brain, heart, aorta and kidneys. Trandolapril and lisinopril prevented 50% of the increase in BP in light and dark period of the day. After the last doses, trandolapril decreased ACE densities by approximately 80% in brain nuclei and heart and lisinopril by approximately 60% in the brain and by approximately 70% in the heart. The two ACE inhibitors prevented right ventricular hypertrophy and attenuated left ventricular hypertrophy but did not affect renal hypertrophy caused by high salt. Both drugs prevented high salt-induced fibrosis in heart, kidney and aorta. CONCLUSION AND IMPLICATION As the ACE inhibitors could completely prevent tissue fibrosis and partially prevent tissue hypertrophy and hypertension, the tissue RAAS may play a critical role in salt-induced fibrosis, but a lesser role in the hypertrophy.
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Affiliation(s)
- B Liang
- Hypertension Unit, University of Ottawa Heart Institute Ottawa, ON, Canada
| | - F H H Leenen
- Hypertension Unit, University of Ottawa Heart Institute Ottawa, ON, Canada
- Author for correspondence:
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McCarty MF. Marinobufagenin may mediate the impact of salty diets on left ventricular hypertrophy by disrupting the protective function of coronary microvascular endothelium. Med Hypotheses 2005; 64:854-63. [PMID: 15694707 DOI: 10.1016/j.mehy.2003.11.043] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2003] [Accepted: 11/21/2003] [Indexed: 01/19/2023]
Abstract
Individuals who eat salty diets and who are "salt-sensitive" tend to have increased left ventricular mass, independent of blood pressure; this phenomenon awaits an explanation. It is clear that local up-regulation of angiotensin II (AngII) production and activity play a key role in the induction of left ventricular hypertrophy (LVH). Recent evidence suggests that a healthy coronary microvascular endothelium opposes this effect by serving as a paracrine source of nitric oxide (NO), a natural antagonist of AngII activity, and that up-regulation of this mechanism can account for the protective role of bradykinin with respect to LVH. The coronary microvasculature also possesses NAD(P)H oxidase activity that can generate superoxide, inimical to the bioactivity of endothelial NO. There is now good reason to believe that the triterpenoid marinobufagenin (MBG), a selective inhibitor of the alpha-1 isoform of the sodium pump, mediates the impact of salty diets on blood pressure; production of MBG by the adrenal cortex is boosted when salt-sensitive animals are fed salty diets. It is hypothesized that coronary microvascular endothelium expresses the alpha-1 isoform of the sodium pump, and that MBG thus can target this endothelium. If that is the case, MBG would be expected to decrease membrane potential in these cells; as a consequence, superoxide production would be up-regulated, NO synthase activity would be down-regulated, and myocardial NO bioactivity would thus be suppressed. This would offer a satisfying explanation for the impact of salt and salt-sensitivity on risk for LVH. If expression of the alpha-1 isoform of the sodium pump is a more general property of vascular endothelium, MBG may suppress NO bioactivity in other regions of the vascular tree, thereby contributing to other adverse effects elicited by salty diets: reduced arterial compliance, medial hypertrophy, impaired endothelium-dependent vasodilation, hypertensive/diabetic glomerulopathy, increased risk for stroke, and hypertension.
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Affiliation(s)
- Mark F McCarty
- Pantox Laboratories, 4622 Santa Fe Street, San Diego, CA 92109, USA.
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Nishiyama A, Yoshizumi M, Rahman M, Kobori H, Seth DM, Miyatake A, Zhang GX, Yao L, Hitomi H, Shokoji T, Kiyomoto H, Kimura S, Tamaki T, Kohno M, Abe Y. Effects of AT1 receptor blockade on renal injury and mitogen-activated protein activity in Dahl salt-sensitive rats. Kidney Int 2004; 65:972-81. [PMID: 14871417 PMCID: PMC2573027 DOI: 10.1111/j.1523-1755.2004.00476.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND The mitogen-activated protein kinase (MAPK) cascade is an important intracellular mediator of angiotensin II (Ang II)-induced cell growth and differentiation. Here, we examined the effect of angiotensin II type 1 receptor (AT1) receptor blockade on renal injury and MAPK activity in Dahl salt-sensitive (DS) rats. METHODS DS rats were maintained on a high (H: 8.0%NaCl, N= 8) or low (L: 0.3%NaCl, N= 7) salt diet, or H + candesartan cilexetil (10 to 15 mg/kg/day, N= 8). Urinary protein excretion (UproteinV), renal cortical collagen content, and glomerular injury (assessed by semiquantitative morphometric analysis) were determined after 4-week treatments. Plasma and kidney Ang II levels were measured by radioimmunoassay. Protein levels of AT1 and AT2 receptors in the renal cortical tissues were analyzed by Western-blotting analyses. MAPKs activities, including extracellular signal-regulated kinases (ERK)1/2, c-Jun NH2-terminal kinases (JNK), p38 MAPK, and Big-MAPK-1 (BMK1), were measured by Western-blotting analyses or in vitro kinase assays. RESULTS DS/H rats showed higher mean blood pressure (MBP), UproteinV, and renal cortical collagen content than DS/L rats. Increased ERK1/2, JNK, and BMK1 activities were observed in renal cortical tissues of DS/H rats (approximately 6.3-, 4.5-, and 2.5-fold, respectively), whereas p38 MAPK activity was unchanged. Plasma Ang II levels were significantly reduced in DS/H rats compared with DS/L rats, whereas kidney Ang II contents and AT1 receptor protein levels were similar. Candesartan did not alter MBP, but significantly reduced UproteinV and collagen content, and ameliorated progressive sclerotic and proliferative glomerular changes. Furthermore, candesartan decreased renal tissue Ang II contents (from 216 +/- 19 to 46 +/- 3 fmol/mL) and ERK1/2, JNK, and BMK1 activities (-45%, -60%, and -70%, respectively) in DS/H rats. CONCLUSION In DS hypertensive rats, some of the renoprotective effects of AT1 receptor blockade are accompanied by reductions in intrarenal Ang II contents and MAPK activity, which might not be mediated through arterial pressure changes.
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Affiliation(s)
- Akira Nishiyama
- Department of Pharmacology, Research Equipment Center, Kagawa Medical University, Kagawa, Japan.
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Abstract
Despite remarkable therapeutic advances in the management of patients with heart failure (HF), the mortality due to this syndrome remains high. Identifying free-living individuals who are at high risk for developing HF may allow implementing strategies that can prevent HF. Prospective epidemiologic studies have identified several risk factors and risk markers for HF. This article reviews current knowledge regarding conventional and newer risk markers for HF, outlines possible underlying mechanisms for the increased HF risk, and provides a framework for clinical multivariate risk prediction using HF risk factors.
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Affiliation(s)
- Satish Kenchaiah
- The National Heart, Lung, and Blood Institute's Framingham Heart Study, Framingham, MA 01702, USA
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8
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McCarty MF. Marinobufagenin may mediate the impact of salty diets on left ventricular hypertrophy by disrupting the protective function of coronary microvascular endothelium. Med Hypotheses 2004; 62:993-1002. [PMID: 15142663 DOI: 10.1016/j.mehy.2003.11.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2003] [Accepted: 11/11/2003] [Indexed: 01/06/2023]
Abstract
Individuals who eat salty diets and who are "salt-sensitive" tend to have increased left ventricular mass, independent of blood pressure; this phenomenon awaits an explanation. It is clear that local up-regulation of angiotensin II (AngII) production and activity play a key role in the induction of left ventricular hypertrophy (LVH). Recent evidence suggests that a healthy coronary microvascular endothelium opposes this effect by serving as a paracrine source of nitric oxide (NO), a natural antagonist of AngII activity, and that up-regulation of this mechanism can account for the protective role of bradykinin with respect to LVH. The coronary microvasculature also possesses NAD(P)H oxidase activity that can generate superoxide, inimical to the bioactivity of endothelial NO. There is now good reason to believe that the triterpenoid marinobufagenin (MBG), a selective inhibitor of the alpha-1 isoform of the sodium pump, mediates the impact of salty diets on blood pressure;production of MBG by the adrenal cortex is boosted when salt-sensitive animals are fed salty diets. It is hypothesized that coronary microvascular endothelium expresses the alpha-1 isoform of the sodium pump, and that MBG thus can target this endothelium. If that is the case, MBG would be expected to decrease membrane potential in these cells;as a consequence, superoxide production would be up-regulated, NO synthase activity would be down-regulated, and myocardial NO bioactivity would thus be suppressed. This would offer a satisfying explanation for the impact of salt and salt-sensitivity on risk for LVH. If expression of the alpha-1 isoform of the sodium pump is a more general property of vascular endothelium, MBG may suppress NO bioactivity in other regions of the vascular tree, thereby contributing to other adverse effects elicited by salty diets: reduced arterial compliance, medial hypertrophy, impaired endothelium-dependent vasodilation, hypertensive/diabetic glomerulopathy, increased risk for stroke, and hypertension.
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Affiliation(s)
- Mark F McCarty
- Pantox Laboratories, 4622 Santa Fe Street, San Diego, CA 92109, USA.
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Mizukami M, Hasegawa H, Kohro T, Toko H, Kudoh S, Zou Y, Aburatani H, Komuro I. Gene Expression Profile Revealed Different Effects of Angiotensin II Receptor Blockade and Angiotensin-Converting Enzyme Inhibitor on Heart Failure. J Cardiovasc Pharmacol 2003; 42 Suppl 1:S1-6. [PMID: 14871019 DOI: 10.1097/00005344-200312001-00002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Although recent clinical studies have indicated that angiotensin II receptor blocker is as effective in treating heart failure as an angiotensin-converting enzyme inhibitor, it is unknown whether their effects are different. Dahl salt-sensitive rats were treated with an angiotensin-converting enzyme inhibitor benazepril, and an angiotensin II receptor blocker candesartan from 11 weeks old. We examined cardiac geometry and function by echocardiography, and histology and gene expression by high-density oligonucleotide arrays using Affymetrix U34 (Affymetrix, Santa Clara, CA, U.S.A.). Dahl salt-sensitive rats fed a high salt diet showed a marked increase in blood pressure and developed concentric hypertrophy at 11 weeks, followed by left ventricle dilation and congestive heart failure by 20 weeks after birth. Although both medications had only a mild antihypertensive effect, they strongly suppressed the development of cardiac hypertrophy, fibrosis and heart failure to the same extent. Gene expression pattern examined by Affymetrix GeneChip (Affymetrix) is quite different between the two drug groups, indicating that angiotensin II receptor blocker and angiotensin-converting enzyme inhibitor prevent heart failure by different mechanisms.
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MESH Headings
- Angiotensin Receptor Antagonists
- Angiotensin-Converting Enzyme Inhibitors/administration & dosage
- Angiotensin-Converting Enzyme Inhibitors/pharmacokinetics
- Angiotensin-Converting Enzyme Inhibitors/therapeutic use
- Animals
- Benzazepines/administration & dosage
- Benzazepines/pharmacokinetics
- Benzazepines/therapeutic use
- Benzimidazoles/administration & dosage
- Benzimidazoles/pharmacokinetics
- Benzimidazoles/therapeutic use
- Biphenyl Compounds
- Disease Models, Animal
- Echocardiography
- Fibrosis/drug therapy
- Fibrosis/pathology
- Fibrosis/prevention & control
- Gene Expression/genetics
- Gene Expression Profiling/methods
- Heart Failure/drug therapy
- Heart Failure/genetics
- Heart Failure/prevention & control
- Hypertension/complications
- Hypertension/drug therapy
- Hypertension/physiopathology
- Hypertrophy, Left Ventricular/drug therapy
- Hypertrophy, Left Ventricular/pathology
- Hypertrophy, Left Ventricular/prevention & control
- Infusions, Parenteral
- Male
- Oligonucleotide Array Sequence Analysis/methods
- Organ Size/drug effects
- Rats
- Rats, Inbred Dahl
- Receptors, Angiotensin/physiology
- Receptors, Angiotensin/therapeutic use
- Sodium Chloride, Dietary/administration & dosage
- Subcutaneous Tissue
- Tetrazoles/administration & dosage
- Tetrazoles/pharmacokinetics
- Tetrazoles/therapeutic use
- Time Factors
- Ventricular Function, Left/drug effects
- Ventricular Function, Left/genetics
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Affiliation(s)
- Miho Mizukami
- Department of Cardiovascular Science and Medicine, Chiba University Graduate School of Medicine, Chiba, Japan
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Sugawara T, Fujii S, Akm Zaman T, Goto D, Kaneko T, Furumoto T, Togashi H, Yoshioka M, Koyama T, Kitabatake A. Coronary capillary remodeling in non-insulin-dependent diabetic rats: amelioration by inhibition of angiotensin converting enzyme and its potential clinical implications. Hypertens Res 2001; 24:75-81. [PMID: 11213033 DOI: 10.1291/hypres.24.75] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Using Otsuka Long Evans Tokushima Fatty (OLETF) rats, a model of human non-insulin-dependent diabetes mellitus (NIDDM) that exhibits hypertension, obesity, hyperglycemia and hyperlipidemia, the role of local angiotensin II in cardiovascular complications at early stages of NIDDM was characterized. OLETF rats were given an angiotensin converting enzyme (ACE) inhibitor, cilazapril (10 mg/kg/day) or vehicle from the age of 5 weeks to 20 weeks. Arteriolar, intermediate and venular capillary proportions were determined by the double-staining method and levels of collagen and non-collagenous proteins were determined by the selective dye-binding method in heart tissues. In OLETF rats at 20 weeks of age, capillary network remodeling (i.e., an increase in arteriolar portions and a decrease in venular portions) and an increase in collagen content were detected. Cilazapril not only exerted favorable effects on markers of diabetes, but also prevented capillary network remodeling and ameliorated the increase in collagen content. These results suggest that 1) capillary network remodeling and increase in extracellular matrix protein levels precede the onset of overt NIDDM in OLETF rats, and 2) angiotensin II may be involved in the pathogenesis of cardiac complications in the early stages of NIDDM.
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Affiliation(s)
- T Sugawara
- Department of Cardiovascular Medicine, Hokkaido University School of Medicine, Sapporo, Japan
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