Department of Neuroscience, Brown University, 185 Meeting St, Providence, RI, 02912, USA.
Graduate School of Life and Medical Sciences, Doshisha University, 1-3, Miyakodani, Tatara, Kyotanabe, Kyoto, 610-0321, Japan.
J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2020 Nov;206(6):831-844. doi: 10.1007/s00359-020-01441-7. Epub 2020 Aug 10.
We used a novel microendoscope system to record simultaneously optical activity (fluorescence of a calcium indicator dye) and electrical activity (multi-unit activity and local field potentials) from the dorsal inferior colliculus of the echolocating bat, Carollia perspicillata. Optically recorded calcium responses to wide-band noise and to frequency-modulated bursts were recorded at probe depths down to 1300 µm, with the majority of active sites encountered at more shallow depths down to 800 µm. Calcium activity exhibited long latencies, within the time span of 50-100 ms after stimulus onset, significantly longer than onset latencies of either multi-unit activity or local field potentials. Latencies and amplitude/latency trading of these electrical responses were consistent with those seen in standard electrophysiological recordings, confirming that the microendoscope was able to record both neural and optical activity successfully. Optically recorded calcium responses rose and decayed slowly and were correlated in time with long-latency negative deflections in local field potentials. These data suggest that calcium-evoked responses may reflect known, sustained inhibitory interactions in the inferior colliculus.
我们使用一种新型的微内窥镜系统，同时记录回声定位蝙蝠 Carollia perspicillata 的背侧下丘的光活性（钙指示剂染料的荧光）和电活性（多单位活动和局部场电位）。在探测深度可达 1300 µm 时，记录到对宽带噪声和调频爆发的光学记录钙响应，大多数活性位点出现在更浅的深度可达 800 µm。钙活性表现出长潜伏期，在刺激开始后的 50-100 ms 时间范围内，明显长于多单位活动或局部场电位的起始潜伏期。这些电反应的潜伏期和幅度/潜伏期交易与标准电生理记录中观察到的一致，证实微内窥镜能够成功记录神经和光学活性。光学记录的钙反应上升和下降缓慢，并且与局部场电位中的长潜伏期负偏移时间相关。这些数据表明，钙引发的反应可能反映了下丘脑中已知的持续抑制相互作用。
