ABSTRACT
Myocardial infarct induction in rat models with isoproterenol is a standard in cardioprotective research on various test substances. The other myocardial infarct induction model uses Lipopolysaccharide (LPS). LPS and isoproterenol show the same induction mechanism on myocardial damage, that is disturbed balance in free radical formation and antioxidative resistance system. This research aims to examine the difference between LPS and Isoproterenol injections in rat models by fibrosis area. This research used a posttest-only control group design with 15 Sprague Dawley rats as samples which were divided into four groups: NaCl control group, LPS 10 mg/mL group, LPS 15 mg/mL group, and isoproterenol group. The LPS and isoproterenol groups were respectively given intraperitoneal injection with LPS and isoproterenol for 14 days, while the control group was not given any treatment. On day 15, they were terminated and measured histopathologically for fibrosis area using a micrometer. This research showed that the groups administered with LPS 10 mg/mL and 15 mg/mL resulted in myocardial infarcts of 51.910 μm2 and 102.512 μm2, respectively, while the group administered with isoproterenol resulted in myocardial infarct of 21.190 μm2. This research showed that LPS 15mg/mL induction is relevant for the development of animal models with Acute Myocardial Infarction.
