Pharmacodynamics of the Glutamate Receptor Antagonists in the Rat Barrel Cortex
Abstract
Epipial application is one of the approaches for drug delivery into the cortex. However, passive diffusion of epipially applied drugs through the cortical depth may be slow, and different drug concentrations may be achieved at different rates across the cortical depth. Here, we explored the pharmacodynamics of the inhibitory effects of epipially applied ionotropic glutamate receptor antagonists CNQX and dAPV on sensory-evoked and spontaneous activity across layers of the cortical barrel column in urethane-anesthetized rats. The inhibitory effects of CNQX and dAPV were observed at concentrations that were an order higher than in slices in vitro, and they slowly developed from the cortical surface to depth after epipial application. The level of the inhibitory effects also followed the surface-to-depth gradient, with full inhibition of sensory evoked potentials (SEPs) in the supragranular layers and L4 and only partial inhibition in L5 and L6. During epipial CNQX and dAPV application, spontaneous activity and the late component of multiple unit activity (MUA) during sensory-evoked responses were suppressed faster than the short-latency MUA component. Despite complete suppression of SEPs in L4, sensory-evoked short-latency multiun...Continue Reading
References
Citations
Methods Mentioned
Software Mentioned
Related Concepts
Related Feeds
Antiarrhythmic Agents: Mechanisms of Action
Understanding the mechanism of action of antiarrhythmic agents is essential in developing new medications as treatment of cardiac arrhythmias is currently limited by the reduced availability of safe and effective drugs. Discover the latest research on Antiarrhythmic Agents: Mechanism of Action here.