Under body O2 imbalance, the Autonomic Nervous System is responsible for redistribution of blood flow with
preference to the most vital organs (brain, heart), while the less vital organs (intestine, GI tract) are hypoperfused.
The aim of this study was to develop and use an animal model for real time monitoring of tissue viability in the brain,
and the small intestine, under various levels of oxygen and blood supply.
Male Wistar rats were anesthetized, the brain cortex and intestinal serosa were exposed and connected by optical fibers
to the Multi-Site Multi-Parametric (MSMP) monitoring system. Tissue blood flow (TBF) and mitochondrial NADH
redox state were monitored simultaneously in the two organs. The rats were subjected to short anoxia, 20 minutes
hypoxia or epinephrine (2& 8&mgr;g/kg I.V.).
Under oxygen deficiency, cerebral blood flow (CBF) was elevated, whereas intestinal TBF was reduced. Mitochondrial
NADH was significantly elevated in both organs. Systemic injection of Adrenaline showed a dose-depended increase in
systemic blood pressure and CBF response whereas, intestinal TBF similarly decreased in both doses. In addition,
NADH was elevated (reduced form) in the intestine whereas oxidation was observed in the brain.
In conclusion, our preliminary results may imply the ability of using of the MSMP for monitoring non-vital organs in
order to detect early changes in the balance between oxygen supply and demand in the body.
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