Rapid increase of intracellular Ca2+concentration caused by aminoadipic acid enantiomers in retinal Müller cells and neurons in vitro

✍ Scribed by Masato Wakakura; Noboru Yamamoto

• Publisher: Springer-Verlag
• Year: 1992
• Tongue: English
• Weight: 846 KB
• Volume: 80
• Category: Article
• ISSN: 0012-4486
• DOI: 10.1007/bf00154389

✦ Synopsis

The ability of the gliotoxic compounds D,L-, D-or L-2-aminoadipic acid (AAA) to increase selectively the intracellular concentration of free calcium ion ([CaZ+]~) was examined in Miiller cells cultured with or without retinal neurons. The monitoring of [Ca2+]~ following exposure to 0.06 to 6 mM AAA was performed by a microfluorometry using a fuorescent Ca z" indicator, Fura-2 acetoxymethyl ester. A rapid increase of [Ca2~]i occurred in the M/iller cells following exposure to a relatively low concentration of the L-isomer. This is compatible with the known strong gliotoxicity of this isomer. The D,L-and D-forms of AAA activated neurons at low concentrations and activated the M/iller cells at higher concentrations. The D-isomer appears to act selectively on retinal neurons and may be an agonist of an excitatory amino acid receptor. These results indicate that the ability of AAA to elevate cytosolic [Ca2+]i depends on the stereospecificity of the AAA and on cell type.