Vitamin C administration improved the baroreceptor reflex index for bradycardia (-2.9 vs -2.0 beats/mm Hg) and reduced myocardial damage during isoproterenol-induced myocardial infarction in rats.
Does acute treatment with vitamin C improve autonomic balancing and reduce myocardial damage in a rat model of isoproterenol-induced acute myocardial infarction?
Acute oral administration of vitamin C reduces myocardial damage, downregulates iNOS expression, and improves autonomic balance in a rat model of isoproterenol-induced myocardial infarction.
Absolute Event Rate: -2.9% vs -2%
BACKGROUND/AIMS: In the present study, we tested whether or not acute antioxidant treatment with vitamin C is able to protect the heart during myocardial infarction. The effects of vitamin C on the autonomic balancing of the heart and on the histopathological and immunohistochemical changes in response to isoproterenol administration (ISO) were evaluated. METHODS: Four groups of male Wistar rats (n = 32) were studied: control; ISO treated; vitamin C treated; ISO + vitamin C treated. ISO 150 mg/kg was administered for 2 consecutive days. Vitamin C (250 mg/kg, oral) was administered 30 min before each ISO treatment. Phenylephrine and sodium nitroprusside were administrated to increase or decrease blood pressure in conscious rats. RESULTS: The baroreceptor reflex index for bradycardia was significantly reduced in the ISO group (control, -3.4 +/- 0.3 beats/mm Hg; ISO -2 +/- 0.4 beats/mm Hg) and vitamin C treatment significantly improved the reflex index (-2.9 +/- 0.7 beats/mm Hg). Treatment with vitamin C showed mild degenerative changes in the myocardial tissue of the ISO group. The antioxidant was able to decrease the inducible nitric oxide (iNOS) expression in rats treated with vitamin C. CONCLUSION: Vitamin C administration proved to be effective in reducing the extent of myocardial damage during ISO-induced myocardial infarction in rats associated with an iNOS downregulation and improving the autonomic balancing of the heart.
Buttros et al. (Thu,) conducted a other in Isoproterenol-Induced Acute Myocardial Infarction (n=32). Vitamin C vs. Isoproterenol alone was evaluated on Baroreceptor reflex index for bradycardia. Vitamin C administration improved the baroreceptor reflex index for bradycardia (-2.9 vs -2.0 beats/mm Hg) and reduced myocardial damage during isoproterenol-induced myocardial infarction in rats.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: