| First Author | Cao JW | Year | 2020 |
| Journal | Neuroscience | Volume | 449 |
| Pages | 147-156 | PubMed ID | 32926954 |
| Mgi Jnum | J:299694 | Mgi Id | MGI:6501362 |
| Doi | 10.1016/j.neuroscience.2020.09.008 | Citation | Cao JW, et al. (2020) Synaptic Transmission from Somatostatin-expressing Interneurons to Excitatory Neurons Mediated by alpha5-subunit-containing GABAA Receptors in the Developing Visual Cortex. Neuroscience 449:147-156 |
| abstractText | Dendrite-targeting somatostatin-expressing interneurons (SST-INs) powerfully control signal integration and synaptic plasticity in pyramidal dendrites during cortical development. We previously showed that synaptic transmission from SST-INs to pyramidal cells (PCs) (SST-IN-->PC) in the mouse visual cortex suddenly declined at around the second postnatal week. However, it is unclear what specific postsynaptic mechanisms underlie this developmental change. Using multiple whole-cell patch-clamp recordings, we found that application of an alpha5-GABAA receptor-selective inverse agonist, alpha5IA, significantly weakened SST-IN-->PC unitary inhibitory postsynaptic currents (uIPSCs) in layer 2/3 of the mouse visual cortex, but had no effect on uIPSCs from SST-INs to other types of interneurons. The extent of alpha5IA-induced reduction of SST-IN-->PC synaptic transmission was significantly larger at postnatal days 11-13 (P11-13) than P14-17. Moreover, alpha5-subunit-containing GABAA receptors (alpha5-GABAARs)-mediated uIPSCs had slow rise and decay kinetics. Apart from pharmacological test, we observed that SST-IN-->PC synapses did indeed contain alpha5-GABAARs by immunogold labeling for electron microscopy. More importantly, coinciding with the weakening of SST-IN-->PC synaptic transmission, the number of alpha5-GABAAR particles in SST-IN-->PC synapses significantly decreased at around the second postnatal week. Together, these data indicate that alpha5-GABAARs are involved in synaptic transmission from SST-INs to PCs in the neocortex, and are significantly diminished around the second postnatal week. |
