Electrophysiological and Morphological Classification of Inhibitory Interneurons in Layer II/III of the Rat Visual Cortex.
- Author:
Duck Joo RHIE
1
;
Ho Young KANG
;
Gyeong Ryul RYU
;
Myung Jun KIM
;
Shin Hee YOON
;
Sang June HAHN
;
Do Sik MIN
;
Yang Hyeok JO
;
Myung Suk KIM
Author Information
1. Department of Physiology, College of Medicine, The Catholic University of Korea, Seoul 137-701, Korea. djrhie@cmc.cuk.ac.kr
- Publication Type:Original Article
- Keywords:
Inhibitory interneurons;
Classification;
Visual cortex;
Layer II/III
- MeSH:
Action Potentials;
Animals;
Classification*;
Interneurons*;
Membrane Potentials;
Neurons;
Rats*;
Visual Cortex*
- From:The Korean Journal of Physiology and Pharmacology
2003;7(6):317-323
- CountryRepublic of Korea
- Language:English
-
Abstract:
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 (> -70 mV) and action potential (AP) width (< 0.9 msec at half amplitude). FS could be differentiated from LS, based on smaller amplitude of the AP (< ~50 mV) and shorter peak-to-trough time (P-T time) of the afterhyperpolarization (< 4 msec). In addition to the shorter AP width, RSNP had the higher input resistance (> 200 M omega) and the shorter P-T time (< 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.
