We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Roselle Polyphenols Exert Potent Negative Inotropic Effects via Modulation of Intracellular Calcium Regulatory Channels in Isolated Rat Heart.
- Authors
Lim, Yi-Cheng; Budin, Siti; Othman, Faizah; Latip, Jalifah; Zainalabidin, Satirah
- Abstract
Roselle ( Hibiscus sabdariffa Linn.) calyces have demonstrated propitious cardioprotective effects in animal and clinical studies; however, little is known about its action on cardiac mechanical function. This study was undertaken to investigate direct action of roselle polyphenols (RP) on cardiac function in Langendorff-perfused rat hearts. We utilized RP extract which consists of 12 flavonoids and seven phenolic acids (as shown by HPLC profiling) and has a safe concentration range between 125 and 500 μg/ml in this study. Direct perfusion of RP in concentration-dependent manner lowered systolic function of the heart as shown by lowered LVDP and d P/d t , suggesting a negative inotropic effect. RP also reduced heart rate (negative chronotropic action) while simultaneously increasing maximal velocity of relaxation (positive lusitropic action). Conversely, RP perfusion increased coronary pressure, an indicator for improvement in coronary blood flow. Inotropic responses elicited by pharmacological agonists for L-type Ca channel [(±)-Bay K 8644], ryanodine receptor (4-chloro- m-cresol), β-adrenergic receptor (isoproterenol) and SERCA blocker (thapsigargin) were all abolished by RP. In conclusion, RP elicits negative inotropic, negative chronotropic and positive lusitropic responses by possibly modulating calcium entry, release and reuptake in the heart. Our findings have shown the potential use of RP as a therapeutic agent to treat conditions like arrhythmia.
- Subjects
ROSELLE; ARRHYTHMIA treatment; POLYPHENOLS; INTRACELLULAR calcium; CALCIUM channels; CARDIOTONIC agents; LABORATORY rats; THERAPEUTICS
- Publication
Cardiovascular Toxicology, 2017, Vol 17, Issue 3, p251
- ISSN
1530-7905
- Publication type
Article
- DOI
10.1007/s12012-016-9379-6