Electrophysiological and Morphological Classification of Inhibitory Interneurons in Layer II/III of the Rat Visual Cortex
Electrophysiological and Morphological Classification of Inhibitory Interneurons in Layer II/III of the Rat Visual Cortex
- Duck-Joo Rhie Ho Young Kang Gyeong Ryul Ryu Myung-Jun Kim Shin Hee Yoon Sang June Hahn Do Sik Min Ya
- 대한생리학회-대한약리학회
- The Korean Journal of Physiology & Pharmacology
- 제7권 제6호
- 등재여부 : KCI등재
- 2003.01
- 317 - 323 (7 pages)
Interneuron diversity is one of the key factors to hinder understanding the mechanism of cortical neural network functions even with their important roles. We characterized inhibitory interneurons in layer II/III of the rat primary visual cortex, using patch-clamp recording and confocal reconstruction, and classified inhibitory interneurons into fast spiking (FS), late spiking (LS), burst spiking (BS), and regular spiking non-pyramidal (RSNP) neurons according to their electrophysiological characteristics. Global parameters to identify inhibitory interneurons were resting membrane potential (<FONT FACE= 바탕 >>⁣70 mV) and action potential (AP) width (<FONT FACE= 바탕 ><0.9 msec at half amplitude). FS could be differentiated from LS, based on smaller amplitude of the AP (<FONT FACE= 바탕 ><∼50 mV) and shorter peak-to-trough time (P-T time) of the afterhyperpolarization (<FONT FACE= 바탕 ><4 msec). In addition to the shorter AP width, RSNP had the higher input resistance (<FONT FACE= 바탕 >>200 M<FONT FACE= 바탕 >Ω) and the shorter P-T time (<FONT FACE= 바탕 ><20 msec) than those of regular spiking pyramidal neurons. Confocal reconstruction of recorded cells revealed characteristic morphology of each subtype of inhibitory interneurons. Thus, our results provide at least four subtypes of inhibitory interneurons in layer II/III of the rat primary visual cortex and a classification scheme of inhibitory interneurons.