Focal cerebral ischemia in rats: effect of hemodilution with alpha-alpha cross-linked hemoglobin on CBF.

Abstract

Hemodilution has had limited success as a treatment of cerebral ischemia. When using a nonoxygen binding fluid, the therapeutic efficacy of hemodilution-induced increases in CBF are offset by concomitant decreases in oxygen content. The effect of hemodilution, with diaspirin alpha-alpha cross-linked hemoglobin (DCLHb), on CBF during middle cerebral artery occlusion was assessed. Rats were hemodiluted to one of the following hematocrits (Hct): (a) 44/Hct, (b) 37/Hct, (c) 30/Hct, (d) 23/Hct, (e) 16/Hct, or (f) 9/Hct. After 10 min of ischemia, CBF was determined with 14C-iodoantipyrine. Coronal brain sections were evaluated for areas with a CBF of 0-10 and 11-20 ml 100 g-1 min-1. In addition, oxygen delivery was calculated. In the center of the ischemic zone, both areas of low CBF were less in the 30/Hct, 23/Hct, and 16/Hct groups compared with the 44/Hct and 37/Hct groups; and both areas were less in the 9/Hct group compared with the other five groups (p < 0.05). For the hemisphere contralateral to occlusion, there was a direct correlation between hematocrit and oxygen delivery. However, for the hemisphere ipsilateral to occlusion, oxygen delivery increased as hematocrit decreased (44/Hct, 8.6 +/- 0.3 vs. 9/Hct, 13.6 +/- 0.4 [mean +/- SD, ml 100 g-1 min-1]). The results of this study support a hypothesis that hemodilution with DCLHb decreases the extent of focal cerebral ischemia.

• Authors: D J Cole, R M Schell, R J Przybelski, J C Drummond, K Bradley
• Journal: Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism (J Cereb Blood Flow Metab) Vol. 12 Issue 6 Pg. 971-6 (Nov 1992) ISSN: 0271-678X [Print] United States
• PMID: 1400651 (Publication Type: Comparative Study, Journal Article)

Chemical References

• Cross-Linking Reagents
• Hemoglobins
• bis(3,5-dibromosalicyl)fumarate
• Aspirin

Topics

• Animals
• Aspirin (analogs & derivatives, pharmacology)
• Brain (blood supply)
• Brain Ischemia (drug therapy)
• Cerebrovascular Circulation (drug effects)
• Cross-Linking Reagents (pharmacology)
• Disease Models, Animal
• Dose-Response Relationship, Drug
• Hemodilution
• Hemoglobins (chemistry, therapeutic use)
• Male
• Rats
• Rats, Inbred SHR