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Abstract
Head trauma (HT) was induced in the left hemisphere of rats by a weight drop device.
Edema was maximal 24 h after HT in the injured zone, and PGE2, TXB2 and 6-keto-PGF1α were elevated in both the injured and remote areas.
The effect of a specific thromboxane synthetase inhibitor, OKY-046, on the outcome
of HT was studied. OKY-046, 100 mg/kg, was given to rats immediately and 8 h after
HT. The neurological severity score (NSS) was evaluated at 1 h after HT, and at 24
h, just prior to sacrifice. Specific gravity (SG) of both hemispheres was measured
after decapitation. Prostaglandins (PGs) were extracted from the site of injury and
from the frontal lobes, remote from the injury, and assayed by RIA. Basal levels of
PGE2 and 6-keto-PGF1α were not reduced by the drug while basal TXB2 levels were lowered. However, the increased production due to HT of all PGs, was
inhibited by OKY-046, especially that of TXB2.
The ratio of ![Math Eq]()
, known to affect vascular tone, was reduced by OKY-046 treatment as a result of TXA2 synthesis inhibition. Still, no effect was found on the neurological outcome (as
evaluated by the NSS), or on edema formation (expressed by reduced SG). Thus, based
on the present findings increased TXA2 synthesis cannot be implicated in the pathophysiology of cerebral edema or dysfunction
following HT.
, known to affect vascular tone, was reduced by OKY-046 treatment as a result of TXA2 synthesis inhibition. Still, no effect was found on the neurological outcome (as
evaluated by the NSS), or on edema formation (expressed by reduced SG). Thus, based
on the present findings increased TXA2 synthesis cannot be implicated in the pathophysiology of cerebral edema or dysfunction
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© 1989 Published by Elsevier Inc.
