Abstract
OBJECTIVES: This study was aimed to assess the cardioprotective role of low molecular weight glycosaminoglycans (LMW-GAG) in isoproterenol (ISO)-induced myocardial infarction (MI) in male Wistar rats. Effect of LMW-GAG on biomolecules, lactate dehydrogenase (LDH)-isoenzyme, and electrocardiographic (ECG)-patterns was studied as evidence of cardioprotection. MATERIALS AND METHODS: Male Wistar rats (140 ± 10 g) were divided into four groups; untreated control (group I), LMW-GAG treated (300 μg/day s. c. for 2 weeks-group II), ISO (85 mg s.c. injected on 13(th) and 14(th) days-group III), and LMW-GAG plus ISO (300 μg/day s. c. for 12 days followed by 85 mg/kg ISO on the end of 13(th) and 14(th) days-group IV). At the end of the experimental period, all animals were terminated. RESULTS: Rats treated with LMW-GAG (300 μg/kg) for 12 days showed significant increasing levels of triglyceride (TG) (both serum and heart tissue), low density lipoprotein (LDL), very low density lipoprotein (VLDL), total cholesterol, uric acid, creatinine, and glucose. However, it significantly decreased the levels of high density lipoprotein (HDL) (serum), plasma total protein, and albumin/globulin (A/G) ratio. ISO also adversely affected the LDH-isoenzymes and caused marked elevation in ST segment. Pretreatment with LMW-GAG (300 μg/kg) daily for a period of 2 weeks prevented the ISO-treated changes. CONCLUSIONS: The results indicate that LMW-GAG exhibits a cardioprotective effect in ISO-induced MI in rats, by maintaining the biomolecules and LDH-isoenzymes.