Objective      To investigate the spatial-temporal characteristics of synaptic inputs received by somatostatin positive (SOM+) interneurons in mouse primary auditory cortex (A1). Methods      After localization of primary A1 with local field potential (LFP) recording

the synaptic inputs

including excitatory and inhibitory postsynaptic currents (EPSCs and IPSCs) were recorded in the SOM+ interneuron and pyramidal cells using voltage-clamp whole-cell recording. The time course and amplitude of EPSCs and IPSCs were compared between the SOM+ interneurons and pyramidal cells to analyze the spatialtemporal characteristics of the inputs received by SOM+ interneurons. Results      The SOM+ interneurons and pyramidal cells showed similar temporal profile

with no significant difference found in the onset latency of both EPSC and IPSC. The peak latency of EPSC was 14.35±2.74 ms and that of IPSC was 18.26±3.24 ms in the SOM+ interneurons

which were significantly shorter than those of pyramidal cells (EPSC

18.81±3.76 ms

P0.05; IPSC: 21.08±3.93 ms

P0.01). However

there were no significant differences in the amplitude of either EPSC or IPSC between the SOM+ interneurons and pyramidal cells (P0.05). Conclusion      The synaptic inputs received by SOM+ interneurons are similar in basic electrophysiological properties to those by pyramidal cells. Yet the temporal differences indicate that the sources of synaptic inputs received by these 2 types of neurons might be different.