This study was performed to investigate whether a fraction of hydroxyethyl starch macromolecules, prepared from pentastarch and known as 'HES-Pz,' with molecular weights of 100,000-1,000,000, protects against blood-brain barrier (BBB) disruption due to intracarotid injection of hyperosmolar mannitol. Rats were anesthetized with isoflurane, and retrograde catheterization of a unilateral external carotid artery was performed. Except for the Control group (n = 8), hemodilution was performed using lactated Ringer's solution (LR group, n = 7), 6% hetastarch (HES group, n = 7), or 6% HES-Pz (HES-Pz group, n = 8) to reduce the hematocrit to about 23%. The BBB transfer coefficient (K(i)) of 14C-α-aminoisobutyric acid was determined after a unilateral intracarotid injection of 25% mannitol. Bloodpressure and hematocrit were similar in all groups. In the control group, K(i) was increased significantly in the ipsilateral cortex (IC) where mannitol was injected (16.3 ± 6.1 vs 4.1 ± 1.4 μL · g-1 · min-1) when compared with the contralateral cortex (CC). K(i) was similar in the CC in all four groups. The K(i) in the IC was significantly lower in the HES-Pz (6.4 ± 3.5 μL · g-1 · min-1) than in the Control, HES, or LR group (16.3 ± 6.1, 19.0 ± 12.9, 17.9 ± 10.8 μL · g-1 · min-1, respectively). Our data suggest that HES-Pz significantly attenuates disruption of the BBB caused by an injection of hyperosmolar mannitol.
ASJC Scopus subject areas
- Anesthesiology and Pain Medicine