P164 Soluble Guanylate Cyclase Stimulators: An Emerging Option in the Treatment of Pressure and Volume Overload Induced Chronic Heart Failure

Pressure and volume overload-induced chronic heart failure (HF) is associated with characteristic cardiac remodeling and ventricular myocardial proteomic alterations, that can lead to the formation of a substrate for arrhythmias. Antiarrhythmic drug therapy is still suboptimal and current therapies are not efficacious enough. The purpose of the current study was therefore to examine the efficiency of nitric oxide (NO)/soluble guanylyl cyclase (sGC)/cyclic guanosine monophosphate (cGMP) stimulator. We used as an experimental model male hypertensive Ren-2 transgenic rats (TGR) (n = 16), normotensive Hannover Sprague–Dawley rats (HSD, n = 17), and a volume-overload HF rat model induced by creating the aortocaval fistula (ACF) in rats of both strains (n = 27). Rats were after the induction of ACF treated by sGC stimulator BAY41-8543 (3 mg/kg/day for 30 weeks) alone or combined with angiotensin-converting enzyme inhibitor (ACEi) Trandolapril (0.25 mg/kg/day for 30 weeks). The age of the animals at the end of the experiment was 40 weeks. Left ventricle tissue and plasma samples were used for further analyses. Blood pressure (BP) was measured by telemetry. Combined treatment with sGC stimulator and ACEi was the most potent in lowering BP. Moreover, supplementation by sGC stimulator alone significantly decreased mortality and increased levels of the antioxidant enzyme superoxide dismutase 1, matrix metalloproteinase 2, total and phosphorylated connexin 43 as well as protein kinase C epsilon, implicated in remodeling of extracellular matrix and intercellular communication, in the left ventricle of TGR rats. Application of the sGC stimulator also slightly normalized elevated collagen deposition and hydroxyproline content in the left ventricular tissue of TGR rats. Unfortunately, we did not observe any effect of the sGC stimulator in the TGR ACF group. These results support the hypothesis that sGC stimulators might represent a class of drugs suitable for the prevention and treatment of related disorders in HF. This work was supported by APVV-21-0410, VEGA 2/0006/23, and EXCELES LX22NPO5104. Supported by APVV-21-0410, VEGA 2/0006/23, and EXCELES LX22NPO5104.