Responses of the Rat Medullary Neurons to Central Penicillin Microinjection

Abstract

Background: The microinjection of penicillin in the medulla oblongata caused different alterations in the global respiratory output. The purpose of this paper was to study the involvement of impulse activity and the functional relationship of bulbar neurons in mechanisms underlying experimentally induced respiratory arrhythmias. Methods: Extracellular activity of neurons and diaphragmatic electromyogram activity were recorded and analyzed. Results: Penicillin microinjection increased the mean discharge rate of bulbar neurons and caused the prolongation of discharge of inspiratory neurons. Cross-correlation analysis revealed new excitatory connections between neurons and a high level of positive synchronization of neuronal activity. Conclusion: The local blockage of synaptic inhibition by penicillin within respiratory areas leads to drastic changes in the functioning of neuronal elements of the single respiratory network.