ACTIONS OF ACROMELIC ACID ON NERVOUS-SYSTEM L-GLUTAMATE RECEPTORS

Acromelic acid, a naturally occurring kainoid, isolated from the mushr oom Clitocybe acromelalga, is a weak displacer of [H-3]L-glutamate bin ding to cockroach (Periplaneta americana) nerve cord membranes. Acrome lic acid (1 mM) displaces similar to 60% of specifically bound [H-3]L- glutamate. When applied by bath perfusion to the cell body membrane of the cockroach fast coxal depressor motor neurone, acromelic acid gene rated slow, prolonged, dose-dependent depolarizations at concentration s of 0.3 mu M and above. Thus acromelic acid is among the most potent of the excitatory amino acids tested to date on insect neurones. (C) 1 994 Wiley-Liss, Inc.