Efflux transport of [3H]GABA across blood-brain barrier after cerebral ischemia-reperfusion in rats.
OBJECTIVE
To study whether the efflux transport of [3H]GABA across the blood-brain barrier (BBB) would be enhanced after cerebral ischemia-reperfusion.


METHODS
Brain efflux index (BEI) of [3H]GABA was determined in ischemic-reperfused rats after [3H]GABA or [3H]GABA combined with unlabeled GABA or probenecid (Pro) was microinjected into the parietal cortex area 2 (Par 2), and brain uptake of Evans blue (EB) was assessed after i.v. EB.


RESULTS
BEI in rats subjected to 10-min ischemia and 30-min, 2-h, 6-h, or 24-h reperfusion were 67%, 83%, 92%, and 87%, respectively, which were higher than that in control (58%). The brain uptake of EB was also considerably increased. Unlabeled GABA or Pro obviously decreased BEI in normal or 6-h reperfused rats, but GABA had no obvious effect on that in 5-min reperfused rats.


CONCLUSIONS
The efflux transport of [3H]GABA was markedly enhanced after cerebral ischemia-reperfusion in rats.
Zhang
Y
Y
Department of Pharmacology, China Pharmaceutical University, Nanjing, China.
Liu
G Q
GQ
Liu
X D
XD
Xiao
X Q
XQ
D000818:Animals; D001812:Blood-Brain Barrier / Q000187:drug effects; D002545:Brain Ischemia / Q000150:complications; D008297:Male; D008845:Microinjections; D011339:Probenecid / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D015427:Reperfusion Injury / Q000209:etiology / Q000378:metabolism*; D005680:gamma-Aminobutyric Acid / Q000493:pharmacokinetics* / Q000494:pharmacology
D005680:gamma-Aminobutyric Acid; D011339:Probenecid