Abstract

To investigate the inotropic effects of dioscin (Dio)in rat isolated-heart and intracellular free calcium concentration in isolated rat ventricular myocytes and to explore its mechanism preliminarily. Left ventricle contractile function was measured using the Langendorff non-recirculating mode of isolated rat heart perfusion. Effects of dioscin and dioscin+SEA0400, sodium-calcium exchanger (NCX) inhibitor, were investigated by measuring left ventricular systolic pressure (LVSP) and left ventricular end diastolic pressure (LVEDP). Also, heart rate (HR), peak rate of rise/fall of left ventricular pressure (±dp/dtmax) of isolated rat heart were calculated; Effects of dioscin and SEA0400 on intracellular free calcium concentration in rat H9c2 cells were measured by Fluo3-AM and then detected the fluorescence intensity with confocal microscopy. With 1 μmol/L dioscin, LVSP was significantly increased by 19.7% (P<0.01) and dp/dtmax was increased by 9.6%; With 1 μmol/L dioscin, the relative fluorescence intensity of intracellular free calcium concentrations were strong significantly(P<0.01). While in presence of SEA0400, the relative fluorescence intensity was changed to 17.09±0.63 (P<0.01) by 1 μmol/L dioscin. With 1 μmol/L dioscin, the relative fluorescence intensity was weak(P<0.01) without calcium or sodium in the extracellular fluid. Dioscin shows positive inotropic effect on isolated rat heart, enhancing the LVSP and +dp/dtmax; Dioscin increases the intracellular concentration of Ca2+ in the cardiac myocytes by increasing Na+ influx and facilitating the reverse mode of the sodium-calcium exchanger.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.