Lee, Jaekwang Woo, Junsung Favorov, Oleg V. Tommerdahl, Mark Lee, C. Justin Whitsel, Barry L. 2024-01-20T14:02:01Z 2024-01-20T14:02:01Z 2021-09-05 2012-09-24 1756-6606 https://pubs.kist.re.kr/handle/201004/128863 Background: GABA, the major inhibitory neurotransmitter in CNS, has been demonstrated to paradoxically produce excitation even in mature brain. However activity-dependent form of GABA excitation in cortical neurons has not been observed. Here we report that after an intense electrical stimulation adult cortical neurons displayed a transient GABA excitation that lasted for about 30s. Results: Whole-cell patch recordings were performed to evaluate the effects of briefly applied GABA on pyramidal neurons in adult rodent sensorimotor cortical slice before and after 1 s, 20 Hz suprathreshold electrical stimulation of the junction between layer 6 and the underlying white matter (L6/WM stimulation). Immediately after L6/WM stimulation, GABA puffs produced neuronal depolarization in the center of the column-shaped region. However, both prior to or 30s after stimulation GABA puffs produced hyperpolarization of neurons. 2-photon imaging in neurons infected with adenovirus carrying a chloride sensor Clomeleon revealed that GABA induced depolarization is due to an increase in [Cl-](i) after stimulation. To reveal the spatial extent of excitatory action of GABA, isoguvacine, a GABA(A) receptors agonist, was applied right after stimulation while monitoring the intracellular Ca2+ concentration in pyramidal neurons. Isoguvacine induced an increase in [Ca2+](i) in pyramidal neurons especially in the center of the column but not in the peripheral regions of the column. The global pattern of the Ca2+ signal showed a column-shaped distribution along the stimulation site. Conclusion: These results demonstrate that the well-known inhibitory transmitter GABA rapidly switches from hyperpolarization to depolarization upon synaptic activity in adult somatosensory cortical neurons. English BMC PRIMARY SOMATOSENSORY CORTEX MACAQUE MONKEYS VISUAL-CORTEX SI CORTEX GABA MODULATION RESPONSES DYNAMICS STIMULATION CL Columnar distribution of activity dependent gabaergic depolarization in sensorimotor cortical neurons Article 10.1186/1756-6606-5-33 1 MOLECULAR BRAIN, v.5 MOLECULAR BRAIN 5 scie scopus 000312593200001 2-s2.0-84866494952 Neurosciences Neurosciences & Neurology Article PRIMARY SOMATOSENSORY CORTEX MACAQUE MONKEYS VISUAL-CORTEX SI CORTEX GABA MODULATION RESPONSES DYNAMICS STIMULATION CL