IV infusion of a drag-reducing polymer extracted from aloe vera prolonged survival time in a rat model of acute myocardial ischaemia

Department of Anesthesiology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
BJA British Journal of Anaesthesia (Impact Factor: 4.35). 02/2007; 98(1):23-8. DOI: 10.1093/bja/ael307
Source: PubMed

ABSTRACT I.V. infusion of drag-reducing polymers (DRPs) has been shown to improve survival time in animals subjected to haemorrhagic shock. We hypothesized that DRPs might prolong survival time in rats following acute myocardial ischaemia (AMI).
Sixteen adult male rats were anaesthetized and mechanically ventilated. An i.v. infusion of either Dextran-40 2.5% (Control, n=8) or Dextran-40 2.5% containing 50 microg ml(-1) of an aloe vera-based DRP (DRP, n=8) was initiated at 3.5 ml h(-1). The left anterior descending coronary artery was ligated. Blood pressure, skin-tissue perfusion, and heart rate were monitored and arterial blood samples were analysed.
The mortality at 60 min following coronary ligation was 0% in the DRP group vs 50% in the control group (P=0.025). DRP-treated animals maintained higher mean arterial pressure [60.9 (5.1) vs 47.5 (5.1) mm Hg, P=0.004] and tissue perfusion [4.2 (3.4) vs 1.2 (0.5) TPU, P=0.029]. The DRP group trended towards better acid-base status with base excess [-5.0 (1.7) vs -8.1 (5.1) mmol litre(-1), P=0.083] and pH [7.42 (0.07) vs 7.35 (0.02), P=0.03].
Administration of nanomolar concentrations of aloe vera-based DRP prolonged survival time in animals with AMI. DRPs may offer a novel method to treat organ/tissue hypoperfusion.

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Available from: Tetsuro Sakai, Mar 24, 2014
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    • "According to Pacella's report, DRPs were shown to reduce microvascular resistance and improve perfusion to myocardium subserved by a flow-limiting coronary stenosis [12]. Additionally, a recent animal study has revealed that intravenous infusion of DRP extracted from aloe vera prolonged the survival time in a rat model of acute MI [11]. Mortality at 60 min after coronary ligation was 0% in the DRP group, vs 50% in the control group. "
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