OBJECTIVE: Despite availability of an array of antihypertensive drugs, malignant hypertension remains a life-threatening condition, and new therapeutic strategies for the treatment of malignant hypertension and malignant hypertension-associated organ damage are needed. The aim of the present study was to assess the effects of nitric oxide (NO)-independent soluble guanylyl cyclase (sGC) stimulator on the course of malignant hypertension. The second aim was to investigate if the treatment with sodium-glucose cotransporter type 2 (SGLT2) inhibitor would augment the expected beneficial actions of the sGC stimulation on the course of malignant hypertension. METHODS: As a model of malignant hypertension, Ren-2 transgenic rats (TGR) treated with nonspecific NO synthase inhibitor (Nω-nitro- l -arginine methyl ester, l -NAME) was used. Blood pressure (BP) was monitored by radiotelemetry, and the treatment was started 3 days before administration of l -NAME. RESULTS: The treatment with sGC stimulator BAY 41-8543, alone or combined with SGLT2 inhibitor empagliflozin, abolished malignant hypertension-related mortality in TGR receiving l -NAME. These two treatment regimens also prevented BP increases after l -NAME administration in TGR, and even decreased BP below values observed in control TGR, and prevented cardiac dysfunction and malignant hypertension-related morbidity. The treatment with the SGLT2 inhibitor empagliflozin did not further augment the beneficial actions of sGC stimulator on the course of malignant hypertension-related mortality. CONCLUSION: The treatment with NO-independent sGC stimulator displayed marked protective actions on the course of malignant hypertension-related mortality and malignant hypertension-related cardiac damage. This suggests that application of sGC stimulator could be a promising therapeutic means for the treatment of malignant hypertension.

• Keywords
• malignant hypertension, renin–angiotensin system, sodium-glucose cotransporter type 2 inhibitor, soluble guanylyl cyclase stimulator,
• MeSH
• Benzhydryl Compounds pharmacology   MeSH
• Sodium-Glucose Transporter 2 Inhibitors MeSH
• Glucosides pharmacology   therapeutic use   MeSH
• Hypertension, Malignant * prevention & control   drug therapy   MeSH
• Blood Pressure drug effects   MeSH
• Rats MeSH
• Morpholines MeSH
• NG-Nitroarginine Methyl Ester pharmacology   MeSH
• Rats, Transgenic MeSH
• Pyrazoles * pharmacology   therapeutic use   MeSH
• Pyrimidines * therapeutic use   pharmacology   MeSH
• Soluble Guanylyl Cyclase * metabolism   MeSH
• Animals MeSH
• Check Tag
• Rats MeSH
• Male MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• BAY 41-8543 MeSH Browser
• Benzhydryl Compounds MeSH
• empagliflozin MeSH Browser
• Sodium-Glucose Transporter 2 Inhibitors MeSH
• Glucosides MeSH
• Morpholines MeSH
• NG-Nitroarginine Methyl Ester MeSH
• Pyrazoles * MeSH
• Pyrimidines * MeSH
• Soluble Guanylyl Cyclase * MeSH

The aim of the present study was to perform kidney messenger ribonucleic acid (mRNA) analysis in normotensive, Hannover Sprague-Dawley (HanSD) rats and hypertensive, Ren-2 renin transgenic rats (TGR) after doxorubicin-induced heart failure (HF) with specific focus on genes that are implicated in the pathophysiology of HF-associated cardiorenal syndrome. We found that in both strains renin and angiotensin-converting enzyme mRNA expressions were upregulated indicating that the vasoconstrictor axis of the renin-angiotensin system was activated. We found that pre-proendothelin-1, endothelin-converting enzyme type 1 and endothelin type A receptor mRNA expressions were upregulated in HanSD rats, but not in TGR, suggesting the activation of endothelin system in HanSD rats, but not in TGR. We found that mRNA expression of cytochrome P-450 subfamily 2C23 was downregulated in TGR and not in HanSD rats, suggesting the deficiency in the intrarenal cytochrome P450-dependent pathway of arachidonic acid metabolism in TGR. These results should be the basis for future studies evaluating the pathophysiology of cardiorenal syndrome secondary to chemotherapy-induced HF in order to potentially develop new therapeutic approaches.

• Keywords
• chemotherapy-induced heart failure, cytochrome P-450, doxorubicin, endothelin system, hypertension, kidney, renal adrenergic system, renin-angiotensin-aldosterone system,
• MeSH
• Doxorubicin adverse effects   MeSH
• Hypertension complications   genetics   physiopathology   MeSH
• Rats MeSH
• Kidney drug effects   physiopathology   MeSH
• RNA, Messenger genetics   MeSH
• Kidney Diseases chemically induced   genetics   physiopathology   MeSH
• Rats, Sprague-Dawley MeSH
• Rats, Transgenic MeSH
• Antibiotics, Antineoplastic adverse effects   MeSH
• Gene Expression Regulation drug effects   MeSH
• Renin-Angiotensin System drug effects   MeSH
• Renin genetics   MeSH
• Heart Failure chemically induced   genetics   physiopathology   MeSH
• Animals MeSH
• Check Tag
• Rats MeSH
• Male MeSH
• Female MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Doxorubicin MeSH
• RNA, Messenger MeSH
• Antibiotics, Antineoplastic MeSH
• Ren2 protein, rat MeSH Browser
• Renin MeSH

We hypothesized that vascular actions of 20-hydroxyeicosatetraenoic acid (20-HETE), the product of cytochrome P450 (CYP450)-dependent ω-hydroxylase, potentiate prohypertensive actions of angiotensin II (ANG II) in Cyp1a1-Ren-2 transgenic rats, a model of ANG II-dependent malignant hypertension. Therefore, we evaluated the antihypertensive effectiveness of 20-HETE receptor antagonist (AAA) in this model. Malignant hypertension was induced in Cyp1a1-Ren-2 transgenic rats by activation of the renin gene using indole-3-carbinol (I3C), a natural xenobiotic. Treatment with AAA was started either simultaneously with induction of hypertension or 10 days later, during established hypertension. Systolic blood pressure (SBP) was monitored by radiotelemetry, indices of renal and cardiac injury, and kidney ANG II levels were determined. In I3C-induced hypertensive rats, early AAA treatment reduced SBP elevation (to 161 ± 3 compared with 199 ± 3 mmHg in untreated I3C-induced rats), reduced albuminuria, glomerulosclerosis index, and cardiac hypertrophy (P<0.05 in all cases). Untreated I3C-induced rats showed augmented kidney ANG II (405 ± 14 compared with 52 ± 3 fmol/g in non-induced rats, P<0.05) which was markedly lowered by AAA treatment (72 ± 6 fmol/g). Remarkably, in TGR with established hypertension, AAA also decreased SBP (from 187 ± 4 to 158 ± 4 mmHg, P<0.05) and exhibited organoprotective effects in addition to marked suppression of kidney ANG II levels. In conclusion, 20-HETE antagonist attenuated the development and largely reversed the established ANG II-dependent malignant hypertension, likely via suppression of intrarenal ANG II levels. This suggests that intrarenal ANG II activation by 20-HETE is important in the pathophysiology of this hypertension form.

• Keywords
• 20-hydroxyeicosatetraenoic acid, cytochrome p450 metabolites, malignant hypertension, renin-angiotensin system,
• MeSH
• Amides pharmacology   MeSH
• Angiotensin II metabolism   MeSH
• Antihypertensive Agents pharmacology   MeSH
• Angiotensin II Type 1 Receptor Blockers pharmacology   MeSH
• Cytochrome P-450 CYP1A1 genetics   MeSH
• Hypertension, Malignant chemically induced   drug therapy   metabolism   MeSH
• Indoles toxicity   MeSH
• Hydroxyeicosatetraenoic Acids antagonists & inhibitors   metabolism   MeSH
• Kidney drug effects   metabolism   MeSH
• Rats, Transgenic MeSH
• Animals MeSH
• Check Tag
• Male MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Research Support, N.I.H., Extramural MeSH
• Names of Substances
• 20-hydroxy-5,8,11,14-eicosatetraenoic acid MeSH Browser
• Amides MeSH
• Angiotensin II MeSH
• Antihypertensive Agents MeSH
• Angiotensin II Type 1 Receptor Blockers MeSH
• Cytochrome P-450 CYP1A1 MeSH
• indole-3-carbinol MeSH Browser
• Indoles MeSH
• Hydroxyeicosatetraenoic Acids MeSH

BACKGROUND/AIMS: We found recently that increasing renal epoxyeicosatrienoic acids (EETs) levels by blocking soluble epoxide hydrolase (sEH), an enzyme responsible for EETs degradation, shows renoprotective actions and retards the progression of chronic kidney disease (CKD) in Ren-2 transgenic hypertensive rats (TGR) after 5/6 renal ablation (5/6 NX). This prompted us to examine if additional protection is provided when sEH inhibitor is added to the standard renin-angiotensin system (RAS) blockade, specifically in rats with established CKD. METHODS: For RAS blockade, an angiotensin-converting enzyme inhibitor along with an angiotensin II type receptor blocker was used. RAS blockade was compared to sEH inhibition added to the RAS blockade. Treatments were initiated 6 weeks after 5/6 NX in TGR and the follow-up period was 60 weeks. RESULTS: Combined RAS and sEH blockade exhibited additional positive impact on the rat survival rate, further reduced albuminuria, further reduced glomerular and tubulointerstitial injury, and attenuated the decline in creatinine clearance when compared to 5/6 NX TGR subjected to RAS blockade alone. These additional beneficial actions were associated with normalization of the intrarenal EETs deficient and a further reduction of urinary angiotensinogen excretion. CONCLUSION: This study provides evidence that addition of pharmacological inhibition of sEH to RAS blockade in 5/6 NX TGR enhances renoprotection and retards progression of CKD, notably, when applied at an advanced stage.

• Keywords
• 5/6 nephrectomy, Chronic kidney disease, Epoxyeicosatrienoic acids, Hypertension, Renin-angiotensin system, Soluble epoxide hydrolase,
• MeSH
• Albuminuria drug therapy   MeSH
• Renal Insufficiency, Chronic drug therapy   mortality   physiopathology   surgery   MeSH
• Epoxide Hydrolases antagonists & inhibitors   MeSH
• Hypertension MeSH
• Angiotensin-Converting Enzyme Inhibitors therapeutic use   MeSH
• Drug Therapy, Combination MeSH
• Rats MeSH
• Survival Rate MeSH
• Nephrectomy MeSH
• Rats, Transgenic MeSH
• Renin-Angiotensin System drug effects   MeSH
• Animals MeSH
• Check Tag
• Rats MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Epoxide Hydrolases MeSH
• Angiotensin-Converting Enzyme Inhibitors MeSH