GABA is the most important inhibitory neurotransmitter in the adult brain. But during early development, GABA acts mostly depolarizing/excitatory (see figure). Considering the hypothesis of an activity-dependent optimization of neuronal circuits we want to determine the biological relevance of GABA-mediated excitation during development for the maturation of neuronal circuits in the brain.
GABA-induced somatic [Ca2+]-transients in an acute brain slice of a 3 day old mouse. A, Confocal fluorescence image of a part of the upper cortical plate in the occipital cortex, stained with the high affinity Ca2+-indicator dye Oregon Green 488 BAPTA-1 (AM). B, Application of GABA (100 µM, 200 ms) induced a transient increase in intracellular (somatic) Ca2+-concentration. Latter is caused by the activation of voltage-gated Ca2+-channels and therefore an indication of GABAergic depolarization.
- Zhang C, Yang S, Flossmann T, Gao S, Witte OW, Nagel G, Holthoff K, Kirmse K (2019) Optimized photo-stimulation of halorhodopsin for long-term neuronal inhibition. BMC Biology 17:95
- Kirmse K (2019) Editorial: GABAergic networks in the developing and mature brain. Brain Res. 1718:10-11. doi: 10.1016/j.brainres.2019.04.029
- Flossmann T, Kaas T, Rahmati V, Kiebel SJ, Witte OW, Holthoff K, Kirmse K (2019) Somatostatin Interneurons Promote Neuronal Synchrony in the Neonatal Hippocampus, Cell Rep 26(12):3173-3182.e5, https://doi.org/10.1016/j.celrep.2019.02.061
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- Rahmati V, Kirmse K, Holthoff K, Kiebel SJ (2018) Ultra-Fast Accurate Reconstruction of Spiking Activity from Calcium Imaging Data. J Neurophysiol doi: 10.1152/jn.00934.2017.
- Rahmati V, Kirmse K, Holthoff K, Schwabe L, Kiebel SJ (2017) Developmental Emergence of Sparse Coding: A Dynamic Systems Approach. Sci Rep 7:13015. DOI:10.1038/s41598-017-13468-z.
- Kirmse K, Hübner CA, Isbrandt D, Witte OW, Holthoff K (2017) GABAergic Transmission during Brain Development: Multiple Effects at Multiple Stages. The Neuroscientist. DOI: 10.1177/1073858417701382
- Kirmse K and Holthoff K (2017) Functions of GABAergic transmission in the immature brain. Neuroforum 23(1):A27–A33.
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