Role of fast inhibitory synaptic transmission in neonatal respiratory rhythmogenesis and pattern formation

Publication date: Available online 28 August 2019Source: Molecular and Cellular NeuroscienceAuthor(s): Michael George Zaki Ghali, Sarah BeshayAbstractSeveral studies have investigated the general role of chloride-based neurotransmission (GABAA and glycinergic signaling) in respiratory rhythmogenesis and pattern formation. In several brain regions, developmental alterations in these signaling pathways have been shown to be mediated by changes in cation-chloride cotransporter (CC) expression. For instance, CC expression changes over the neonatal period in medullary respiratory nuclei and other brain/spinal cord regions in a manner which decreases the cellular import, and increases the export, of chloride ions, shifting reversal potentials for chloride to progressively more negative values with maturation. In slice preparations of the same, this is related to an excitatory-to-inhibitory shift of GABAA- and glycinergic signaling. In medullary slices, GABAA-/glycinergic signaling in the early neonatal period is excitatory, becoming inhibitory over time. Additionally, blockade of the Na+/K+/2Cl− cotransporter, which imports these ions via secondary active transport, converts excitatory response to inhibitory ones. These effects have not been yet investigated at the individual respiratory-related neuron level to occur in intact (in vivo or in situ) animal preparations, which in contrast to slices, possess normal network connectivity and natural sources of tonic drive. Developmenta...
Source: Molecular and Cellular Neuroscience - Category: Neuroscience Source Type: research