Cardioprotective Effects of Methanolic Extract of Scrophularia frigida on Ischemia-Reperfusion-Induced Injuries in Isolated Rat Heart

Myocardial infarction is a common presentation of coronary artery disease and the leading cause of death worldwide. The present study investigated potential resistance to ischemia-reperfusion (I/R) injuries following administration of methanolic (MeOH) extract of Scrophularia frigida (S. frigida) in isolated rat heart. Male Wistar rat hearts (n= 8-10) were isolated and allowed to equilibrate for 20 min, and then subjected to 30 min regional ischemia followed by 120 min reperfusion. In the control group, Krebs-Henseleit (K/H) solution was perfused. However, in the treatment groups K/H solution containing 1, 5, and 10 µg/cc of extract was infused. In addition, total phenol, total flavonoid content and antioxidant property were evaluated and extract was subjected to phytochemical analysis. Administration of extract improved the flow rate, developed pressure as well as max and min left ventricular dp/dt. Number and duration of VT were significantly reduced by all extract concentrations in ischemic phase. In reperfusion phase, significant decreases in single and total arrhythmias were seen. Furthermore, concentrations of 5 and 10 µg/cc of extract remarkably decreased the infarct size. Generally, the methanolic extract of S. frigida exhibited a protective effect against I/R-induced injures, which might be due to the antioxidant activiies of iridoids and phenolics.