5-( N-Ethyl- N-isopropyl)-amiloride inhibits amino acid release from the ischemic rat cerebral cortex: role of Na +–H + exchange

• Published in: Brain research 1998-11, Vol.812 (1), p.297-300
• Main Authors: Phillis, John W, O'Regan, Michael H, Song, Dekun
• Format: Article
• Language: English
• Subjects: 5-( N-Ethyl- N-isopropyl)-amiloride; Acidosis; Amiloride; Amiloride - analogs & derivatives; Amiloride - pharmacology; Amino acid; Amino Acids - metabolism; Animals; Biological and medical sciences; Brain Ischemia - drug therapy; Cerebral ischemia; Glutamate; Male; Medical sciences; Na +/H + exchange; Neurology; Rats; Rats, Sprague-Dawley; Sodium-Hydrogen Exchangers - antagonists & inhibitors; Vascular diseases and vascular malformations of the nervous system
• ISSN: 0006-8993; 1872-6240
• DOI: 10.1016/S0006-8993(98)00984-6

The effect of the selective Na +/H + antiporter inhibitor 5-( N-ethyl- N-isopropyl)-amiloride (EIPA) on amino acid release from the ischemic/reperfused rat cerebral cortex was investigated using a cortical cup technique. EIPA (25 μM in artificial cerebrospinal fluid), applied topically, inhibited the ischemia–reperfusion evoked efflux of aspartate, glutamate, γ-aminobutyric acid, taurine and phosphoethanolamine. Reductions in the ischemia-evoked releases of these amino acids suggest that ischemia precipitates acidosis, Na +/H + exchange and cell swelling with amino acid release as the cells mount a regulatory volume decrease response. EIPA, by blocking Na +/H + exchange, would reduce cell swelling and the resulting amino acid release.