Dissolve 2.5 µg AP5 powder per 1.0 µl of saline (in my experience this is a small concentration so you might need to dissolve 0.00125 g / 0.5 ml in order to get reliable weight measurements).

This will be acidic so bring it up to 7.4 pH with a few µL of NaOH.

Infuse 2.0 µl / hemisphere at 0.4 µl / min.