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Document Type |
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Article In Journal |
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Document Title |
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Awad, HA; Sabh A F; Nehal M Bahgat; Magda HM Youssef & Gihan I M El Salamony. (2003). Cardiac Dysfunction in Experimental Hyperuricemia. Ain Shams Medical Journal, Awad, HA; Sabh A F; Nehal M Bahgat; Magda HM Youssef & Gihan I M El Salamony. (2003). Cardiac Dysfunction in Experimental Hyperuricemia. Ain Shams Medical Journal, |
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Document Language |
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English |
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Abstract |
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The Cardiovascular effects of short-term hyperuricemia as well as chronic hyperuricemia for four and eight weeks durations were studied in rats. Short-term hyperuricemia produced by infusion of uric acid (0.45 mg/kg/min. for 2 hours) produced significant changes in ECG pattern, mean arterial blood pressure (MAP) values, and cardiac weights compared to their controls. Isolated hearts from this group perfused in Langendorff preparation showed insignificant changes in chronotropic as well as inotropic activities compared to their saline control.
Chronic moderate hyperuricemia was produced by i.p injection of probenecid (50mg/kg/day) for four and eight weeks. Rats in this model showed, except for increased R-voltage and corrected Q-T interval, ECG pattern and MAP levels comparable to control rats. Results obtained from isolated hearts also were not significantly different from control rats concerning maximum responses in chronotropic and inotropic activities and myocardial flow rate (MFR).
Cardiac weights in eight weeks probenecid – treated rats were signicantly increased. Basal MFR showed non significant changes. However, MFR in response to isoproterenol infusion in this group expressed per gram left ventricle was reduced compared to preinfusion values. Cardiac weights of eight weeks treated group showed significant cardiac hypertrophy.
Allantoxanamide – induced hyperuricemia (250/mg/kg every other day for four weeks) in rats produced bradycardia, prolonged Q-T intervals and increased R-voltage compared to control rats. MAP values were lower in this model of hyperuricemia. Cardiac weights were comparable to their controls.
However, studies on isolated hearts from group showed higher values of basal HR and lower chronotropic reserve compared to their controls. Data of inotropic activity were also comparable to control rats, but basal MFR were significantly lower than that of control group.
The group of rats treated with the hypouricemic drug allopurinol (50 mg/kg/day) concomitant with allantoxanamide treatment for four weeks to minimize the effect of hyperuricemia. In this group, the significant decrease of HR seen in the four weeks allantoxanamide – treated group was abolished. MAP – values were not significantly changed by allopurinol treatment. Cardiac weights showed significant decrease in left ventricular weights compared to the allantoxanamide hyperuricemia group. Basal MFR expressed per gram left ventricle was significantly increased compared to allantoxanamide group. Also, MFR values were higher in response to isoproterenol infusion. Isolated hearts from this model of allantoxanamide-allopurinol treated rats showed non significant changes in basal chronotropic and inotropic activities compared to alantoxanaminde – treated rats.
The interrelationships between plasma uric acid and each of in vivo HR, R-voltage, relative left ventricular weight, packed cell volume (PCV) values and MFR in the different models were also studied in the different models of hyperuricemia. Also, correlations between PCV values and MAP and left ventricularweights are presented and their significance discussed. The physiological mechanism and the significance of the obtained results are discussed. |
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ISSN |
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0940-5429 |
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Journal Name |
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Ain Shams Medical Journal |
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Volume |
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54 |
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Issue Number |
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7-9 |
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Publishing Year |
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2003 AH
2003 AD |
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Article Type |
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Article |
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Added Date |
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Monday, March 15, 2010 |
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Researchers
| حسام عوض | Awad, Hosam | Researcher | Doctorate | |
| عبدالرحمن فهمي | Fahmi, Abdulrahman | Researcher | Doctorate | |
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