| Abstrakt: |
Introduction: Long term exposure to fluoride is toxic to bones and organs like heart, liver, lung and kidney. Fluoride toxicities induced by oxygen sensing cell signal pathways, hence low oxygen microenvironment and fluoride exposure might have similar toxic manifestation in physiological system and a possible protective mechanism by antioxidant like l-ascorbic acid supplementation. Aim: To investigate the supplementation of l-ascorbic acid on hypoxia or sodium fluoride (NaF) alone or in combination in cardiovascular electrophysiology of male albino rats. Materials &Method: Male albino rats were divided into 8 groups (n= 6/group), group I(control), group II (l-ascorbic acid, 50 mg/100g. b.wt), group III (hypoxia, 10% O2), group IV (NaF ;20 mg/kg b.wt/day ; ip), group V (NaF + hypoxia, 10% O2), group VI (l–ascorbic acid + hypoxia, 10% O2), group VII (l-ascorbic acid + NaF) and group VIII (l-ascorbic acid + NaF + hypoxia, 10% O2). The treatments were carried for 21 days. Gravimetry, electrophysiological parameters like noninvasive blood pressure (NIBP), mean arterial pressure (MAP), heart rate (HR), respiratory rate (RR), LF (low frequency), HF (high frequency) and LF/HF ratio were measured. Histopathological evaluations were done to identify changes in myocardial tissue (ventricle). Results: Electrophysiological evaluation showed significant alteration in MAP in rats treated with hypoxia (group III), NaF (group IV) and NaF with hypoxia (group V). In case of l-ascorbic acid supplementation in group VI, VII and VIII showed remarkable improvement of altered MAP levels. Alteration in heart rate, LF, HF, LF/HF ratio and histopathology in myocardial tissue(ventricle) in rats treated with hypoxia, NaF and hypoxia with NaF indicate cardiac autonomic dysfunctions, but simultaneous supplementation with l-ascorbic acid were found to be beneficial against fluoride and hypoxia induced alteration of cardiovascular functions. Conclusion: The study indicates a protective role of l-ascorbic acid on cardiovascular pathophysiology in rats treated with NaF, hypoxia and in combination of both. [ABSTRACT FROM AUTHOR] |
