Alkyl-substituted benzothiadiazides (BTDs) were tested for their effects on (R,S)-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-type glutamate receptors. In excised patches, the 5 -ethyl derivative “D1” blocked the desensitization of AMPA receptor currents during prolonged application of glutamate (EC50, 36 M), and it slowed deactivation of responses elicited by 1-ms glutamate pulse...