This study investigated whether ivabradine, a selective If current inhibitor reducing heart rate (HR), is able to improve survival and prevent left ventricular (LV) remodeling in isoproterenol-induced heart damage. Wistar rats were treated for 6 weeks: controls (n = 10), ivabradine (10 mg/kg/day orally; n = 10), isoproterenol (5 mg/kg/day intraperitoneally; n = 40), and isoproterenol plus ivabradine (n = 40). Isoproterenol increased mortality, induced hypertrophy of both ventricles and LV fibrotic rebuilding, and reduced systolic blood pressure (SBP). Ivabradine significantly increased survival rate (by 120%) and prolonged average survival time (by 20%). Furthermore, ivabradine reduced LV weight and hydroxyproline content in soluble and insoluble collagen fraction, reduced HR and attenuated SBP decline. We conclude that ivabradine improved survival in isoproterenol-damaged hearts.

• Klíčová slova
• heart hypertrophy, isoproterenol, ivabradine, mortality, remodeling, survival,
• MeSH
• funkce levé komory srdeční účinky léků   MeSH
• infarkt myokardu patofyziologie   MeSH
• isoprenalin MeSH
• ivabradin aplikace a dávkování   farmakologie   MeSH
• kardiotonika aplikace a dávkování   farmakologie   MeSH
• krysa rodu Rattus MeSH
• modely nemocí na zvířatech MeSH
• potkani Wistar MeSH
• remodelace komor účinky léků   MeSH
• srdeční selhání farmakoterapie   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• isoprenalin MeSH
• ivabradin MeSH
• kardiotonika MeSH

Hypertension-induced renal injury is characterized by structural kidney alterations and function deterioration. Therapeutics for kidney protection are limited, thus novel renoprotectives in hypertension are being continuously sought out. Ivabradine, an inhibitor of the If current in the sinoatrial node reducing heart rate (HR), was shown to be of benefit in various cardiovascular pathologies. Yet, data regarding potential renoprotection by ivabradine in hypertension are sparse. Thirty-six adult male Wistar rats were divided into non-diseased controls and rats with NG-nitro-L-arginine methyl ester (L-NAME)-induced hypertension to assess ivabradine's site-specific effect on kidney fibrosis. After 4 weeks of treatment, L-NAME increased the average systolic blood pressure (SBP) (by 27%), decreased glomerular density (by 28%) and increased glomerular tuft area (by 44%). Moreover, L-NAME induced glomerular, tubulointerstitial, and vascular/perivascular fibrosis by enhancing type I collagen volume (16-, 19- and 25-fold, respectively). L-NAME also increased the glomerular type IV collagen volume and the tubular injury score (3- and 8-fold, respectively). Ivabradine decreased average SBP and HR (by 8 and 12%, respectively), increased glomerular density (by 57%) and reduced glomerular tuft area (by 30%). Importantly, ivabradine decreased type I collagen volume at all three of the investigated sites (by 33, 38, and 72%, respectively) and enhanced vascular/perivascular type III collagen volume (by 67%). Furthermore, ivabradine decreased the glomerular type IV collagen volume and the tubular injury score (by 63 and 34%, respectively). We conclude that ivabradine attenuated the alterations of glomerular density and tuft area and modified renal fibrosis in a site-specific manner in L-NAME-hypertension. It is suggested that ivabradine may be renoprotective in hypertensive kidney disease.

• Klíčová slova
• L-NAME, fibrosis, hypertension, ivabradine, nephroprotection,
• Publikační typ
• časopisecké články MeSH

Ivabradine, the selective inhibitor of the If current in the sinoatrial node, exerts cardiovascular protection by its bradycardic effect and potentially pleiotropic actions. However, there is a shortage of data regarding ivabradine's interaction with the renin-angiotensin-aldosterone system (RAAS). This study investigated whether ivabradine is able to protect a hypertensive heart in the model of L-NAME-induced hypertension and to interfere with the RAAS. Four groups (n = 10/group) of adult male Wistar rats were treated as follows for four weeks: control, ivabradine (10 mg/kg/day), L-NAME (40 mg/kg/day), and L-NAME plus ivabradine. L-NAME administration increased systolic blood pressure (SBP) and left ventricular (LV) weight, enhanced hydroxyproline concentration in the LV, and deteriorated the systolic and diastolic LV function. Ivabradine reduced heart rate (HR) and SBP, and improved the LV function. The serum concentrations of angiotensin Ang 1⁻8 (Ang II), Ang 1⁻5, Ang 1⁻7, Ang 1⁻10, Ang 2⁻8, and Ang 3⁻8 were decreased in the L-NAME group and ivabradine did not modify them. The serum concentration of aldosterone and the aldosterone/Ang II ratio were enhanced by L-NAME and ivabradine reduced these changes. We conclude that ivabradine improved the LV function of the hypertensive heart in L-NAME-induced hypertension. The protective effect of ivabradine might have been associated with the reduction of the aldosterone level.

• Klíčová slova
• L-NAME, aldosterone, angiotensin II, fibrosis, heart function, hypertension, ivabradine,
• MeSH
• aldosteron krev   MeSH
• angiotensiny krev   MeSH
• biologické markery MeSH
• echokardiografie MeSH
• funkce levé komory srdeční účinky léků   MeSH
• hydroxyprolin krev   metabolismus   MeSH
• hypertenze diagnóza   etiologie   metabolismus   patofyziologie   MeSH
• ivabradin farmakologie   MeSH
• kardiovaskulární látky farmakologie   MeSH
• kolagen metabolismus   MeSH
• krevní tlak účinky léků   MeSH
• krysa rodu Rattus MeSH
• modely nemocí na zvířatech MeSH
• NG-nitroargininmethylester škodlivé účinky   MeSH
• renin-angiotensin systém účinky léků   MeSH
• renin krev   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• aldosteron MeSH
• angiotensiny MeSH
• biologické markery MeSH
• hydroxyprolin MeSH
• ivabradin MeSH
• kardiovaskulární látky MeSH
• kolagen MeSH
• NG-nitroargininmethylester MeSH
• renin MeSH