Combination of chronic kidney disease (CKD) and heart failure (HF) results in extremely high morbidity and mortality. The current guideline-directed medical therapy is rarely effective and new therapeutic approaches are urgently needed. The study was designed to examine if renal denervation (RDN) will exhibit long-standing beneficial effects on the HF- and CKD-related morbidity and mortality. Fawn-hooded hypertensive rats (FHH) served as a genetic model of CKD and fawn-hooded low-pressure rats (FHL) without CKD served as controls. HF was induced by creation of aorto-caval fistula (ACF). RDN was performed 28 days after creation of ACF and the follow-up period was 70 days. ACF FHH subjected to sham-RDN had survival rate of 34 % i.e. significantly lower than 79 % observed in sham-denervated ACF FHL. RDN did not improve the condition and the final survival rate, both in ACF FHL and in ACF FHH. In FHH basal albuminuria was markedly higher than in FHL, and further increased throughout the study. RDN did not lower albuminuria and did not reduce renal glomerular damage in FHH. In these rats creation of ACF resulted in marked bilateral cardiac hypertrophy and alterations of cardiac connexin-43, however, RDN did not modify any of the cardiac parameters. Our present results further support the notion that kidney damage aggravates the HF-related morbidity and mortality. Moreover, it is clear that in the ACF FHH model of combined CKD and HF, RDN does not exhibit any important renoprotective or cardioprotective effects and does not reduce mortality. Key words Chronic kidney disease, Heart failure, Renal denervation, Fawn-hooded hypertensive rats.

• MeSH
• Denervation methods   MeSH
• Hypertension * physiopathology   complications   MeSH
• Cardio-Renal Syndrome * physiopathology   surgery   etiology   MeSH
• Rats MeSH
• Kidney * innervation   MeSH
• Disease Models, Animal MeSH
• Sympathectomy * methods   MeSH
• Animals MeSH
• Check Tag
• Rats MeSH
• Male MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH

This study evaluates the effects of chronic treatment with EET-A, an orally active epoxyeicosatrienoic acid (EETs) analog, on the course of aorto-caval fistula (ACF)-induced heart failure (HF) in Ren-2 transgenic rats (TGR), a model characterized by hypertension and augmented activity of the renin-angiotensin system (RAS). The results were compared with standard pharmacological blockade of the RAS using angiotensin-converting enzyme inhibitor (ACEi). The rationale for employing EET-A as a new treatment approach is based on our findings that apart from increased RAS activity, untreated ACF TGR also shows kidney and left ventricle (LV) tissue deficiency of EETs. Untreated ACF TGR began to die 17 days after creating ACF and were all dead by day 84. The treatment with EET-A alone or ACEi alone improved the survival rate: in 156 days after ACF creation, it was 45.5% and 59.4%, respectively. The combined treatment with EET-A and ACEi appeared to improve the final survival to 71%; however, the difference from either single treatment regimen did not reach significance. Nevertheless, our findings support the notion that targeting the cytochrome P-450-dependent epoxygenase pathway of arachidonic acid metabolism should be considered for the treatment of HF.

• Keywords
• Ren-2 transgenic rats, angiotensin-converting enzyme inhibitor, aorto-caval fistula, congestive heart failure, cytochrome P-450, epoxyeicosatrienoic acids, hypertension, renin-angiotensin system, volume-overload heart failure,
• Publication type
• Journal Article MeSH

Cytochrome P450 (CYP-450) metabolites of arachidonic acid: epoxyeicosatrienoic acids (EETs) and 20-hydroxyeicosatetraenoic acid (20-HETE) have established role in regulation of blood pressure (BP) and kidney function. EETs deficiency and increased renal formation of 20-HETE contribute to hypertension in spontaneously hypertensive rats (SHR). We explored the effects of 14,15-EET analog (EET-A) and of 20-HETE receptor blocker (AAA) on BP and kidney function in this model. In anesthetized SHR the responses were determined of mean arterial blood pressure (MABP), total renal (RBF), and cortical (CBF) and inner-medullary blood flows, glomerular filtration rate and renal excretion, to EET-A, 5 mg/kg, infused i.v. for 1 h to rats untreated or after blockade of endogenous EETs degradation with an inhibitor (c-AUCB) of soluble epoxide hydrolase. Also examined were the responses to AAA (10 mg/kg/h), given alone or together with EET-A. EET-A significantly increased RBF and CBF (+30% and 26%, respectively), seen already within first 30 min of infusion. The greatest increases in RBF and CBF (by about 40%) were seen after AAA, similar when given alone or combined with EET-A. MABP decreased after EET-A or AAA but not significantly after the combination thereof. In all groups, RBF, and CBF increases preceded the decrease in MABP. We found that in SHR both EET-A and AAA induced renal vasodilation but, unexpectedly, no additive effect was seen. We suggest that both agents have a definite therapeutic potential and deserve further experimental and clinical testing aimed at introduction of novel antihypertensive therapy.

• Keywords
• 20-HETE antagonist, EET analog, epoxyeicosatrienoic acids, hypertension, soluble epoxide hydrolase,
• Publication type
• Journal Article MeSH

OBJECTIVE: We evaluated the hypothesis that the development of renal dysfunction and congestive heart failure (CHF) caused by volume overload in rats with angiotensin II (ANG II)-dependent hypertension is associated with altered renal vascular responsiveness to ANG II and to epoxyeicosatrienoic acids (EETs). METHODS: Ren-2 transgenic rats (TGRs) were used as a model of ANG II-dependent hypertension. CHF was induced by volume overload achieved by the creation of the aorto-caval fistula (ACF). Renal blood flow (RBF) responses were determined to renal arterial administration of ANG II, native 11,12-EET, an analog of 14,15-EETs (EET-A), norepinephrine (NE), acetylcholine (Ach) and bradykinin (Bk) in healthy (i.e., sham-operated) TGR and ACF TGR (5 weeks after ACF creation). RESULTS: Selective intrarenal administration of neither vasoactive drug altered mean arterial pressure in any group. Administration of ANG II caused greater decreases in RBF in ACF TGR than in sham-operated TGR, whereas after administration of NE the respective decreases were comparable in the 2 groups. Administration of Ach and Bk elicited significantly higher RBF increases in ACF TGR as compared with sham-operated TGR. In contrast, administration of 11,12-EET and EET-A caused significantly smaller RBF increases in ACF TGR than in sham-operated TGR. CONCLUSION: The findings show that 5 weeks after creation of ACF, the TGR exhibit exaggerated renal vasoconstrictor responses to ANG II and reduced renal vasodilatory responses to EETs, suggesting that both these alterations might play an important role in the development of renal dysfunction in this model of CHF.

• Keywords
• Acetylcholine, Angiotensin II, Aorto-caval fistula, Bradykinin, Congestive heart failure, Epoxyeicosatrienoic acid, Hypertension, Norepinephrine, Renal blood flow, Renal dysfunction, Renal vascular reactivity,
• MeSH
• Angiotensin II adverse effects   MeSH
• Pulmonary Artery abnormalities   physiopathology   MeSH
• Arterio-Arterial Fistula physiopathology   MeSH
• Hypertension chemically induced   complications   MeSH
• Rats MeSH
• Rats, Transgenic MeSH
• Renal Circulation drug effects   MeSH
• Heart Failure complications   physiopathology   MeSH
• Vasodilation drug effects   MeSH
• Vasoconstriction drug effects   MeSH
• Vasoconstrictor Agents pharmacology   MeSH
• Animals MeSH
• Check Tag
• Rats MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Angiotensin II MeSH
• Vasoconstrictor Agents MeSH