Kinetic variability of AMPA receptors among olfactory bulb neurons in culture.

AMPA receptors, which are composed of four subunits (GluR1-4), help mediate synaptic transmission at most excitatory synapses in the brain. Their subunit composition influences the kinetics of AMPA receptor deactivation and desensitization, thus, the efficacy of synaptic transmission. Immunohistochemical data suggest that AMPA receptor subunit expression in the olfactory bulb (OB) follows a distinct laminar and cellular distribution. However, little is known about the kinetic properties of AMPA receptors on OB neurons. In this study, we used kinetic analysis and pharmacologic methods to demonstrate that the rate and extent of desensitization of OB AMPA receptors vary within and between neuronal subtypes. Such variability suggests that a broad functional diversity of AMPA receptors contributes to olfactory information processing.