Effect of Hemodilution on Regional Cerebral Blood Flow During Chronic Hyperglycemia in Rats
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چکیده
Regional cerebral blood flow decreases during chronic hyperglycemia, a condition frequently associated with elevated hematocrit. To test the hypothesis that an elevated hematocrit is responsible for the reduced regional cerebral blood flow during chronic hyperglycemia, I used isovolemic hemodilution to normalize the hematocrit in seven normoglycemic and seven streptozotocin-treated (hyperglycemic) rats. Regional cerebral blood flow was measured in 28 awake, restrained rats (14 normoglycemic and 14 hyperglycemic) using [C]iodoantipyrine and dissection of 17 brain regions. Hemodilution lowered the hematocrit by 6 units (13%) and increased the average cerebral blood flow by 14%. Chronic hyperglycemia did not elevate the hematocrit, but it decreased the average cerebral blood flow by 12% and that in nine nontelencephalic brain regions by 17%. This effect was independent of changes in hematocrit caused by hemodilution. The reduced regional cerebral blood flow during chronic hyperglycemia is not caused by elevated hematocrit. (Stroke 1990;21:1072-1076)
منابع مشابه
Effect of hemodilution on regional cerebral blood flow.
Regional cerebral blood flow decreases during chronic hyperglycemia, a condition frequently associated with elevated hematocrit. To test the hypothesis that an elevated hematocrit is responsible for the reduced regional cerebral blood flow during chronic hyperglycemia, I used isovolemic hemodilution to normalize the hematocrit in seven normoglycemic and seven streptozotocin-treated (hyperglycem...
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