How Microelectrode Array-Based Chick Forebrain Neuron Biosensors Respond to Glutamate NMDA Receptor Antagonist AP5 and GABA(A) Receptor Antagonist Musimol.

We have established a long-term, stable primary chick forebrain neuron (FBN) culture on a microelectrode array platform as a biosensor system for neurotoxicant screening and for neuroelectrophysiological studies for multiple purposes. This paper reports some of our results, which characterize the biosensor pharmacologically. Dose-response experiments were conducted using NMDA receptor antagonist AP5 and GABA(A) receptor agonist musimol (MUS). The chick FBN biosensor (C-FBN-biosensor) responds to the two agents in a pattern similar to that of rodent counterparts; the estimated EC(50)s (the effective concentration that causes 50% inhibition of the maximal effect) are 2.3 μM and 0.25 μM, respectively. Intercultural and intracultural reproducibility and long-term reusability of the C-FBN-biosensor are addressed and discussed. A phenomenon of sensitization of the biosensor that accompanies intracultural reproducibility in paired dose-response experiments for the same agent (AP5 or MUS) is reported. The potential application of the C-FBN-biosensor as an alternative to rodent biosensors in shared sensing domains (NMDA receptor and GABA(A) receptor) is suggested.