A study on the synaptic relation between glycine-immunoreactive neurons and cuneothalamic relay neurons in the rat cuneate nucleus

• Main Authors: Hsieh,Wei-Fang, 謝維芳
• Other Authors: Wen,Jenn-Yuan
• Format: Others
• Language: zh-TW
• Published: 1995
• Online Access: http://ndltd.ncl.edu.tw/handle/69641596943437889533

碩士 === 國立臺灣大學 === 解剖學研究所 === 83 === The present study aims to localize the glycine-immunoreactive (glycine-IR) neurons and terminals in the rat cuneate nucleus. Pre-embedding immunostaining was employed to identify the glycine-IR neurons and postembedding immunogold labelling was used to elucidate the glycine-IR terminals in the rat cuneate nucleus. Retrograde transport of wheat germ agglutinin conjugated with horseradish peroxidase complex (WGA-HRP) was use to label CTNs and anti-glycine postembedding immunogold labelling was used for the identification of glycine-IR terminals. Glycine-IR cell bodies were located in the whole rostrocaudal extent of the nucleus and were distributed randomly. The morphology of glycine- IR neuron included round and spindle shape (mean density = 0.86 cell / 10000mm2, SD= 0.32). About 20% of the neurons were glycine-immunoreactive (mean area=167.868.1mm2). At the electron microscopic level, about 24.7% of the terminals (n = 587) surveyed were immunogold-labeled glycine-IR terminals. They were mostly medium size (mean = 1.44 0.7mm2, n= 145) and contained either flatten or pleomorphic vesicles. Most of Glycine-IR terminal formed symmetric synapses with dendrites of various sizes. In addition, glycine-IR terminal also made synaptic contact with axon terminal of unknown origin. The synaptic relation between the glycine-immunoreative (glycine-IR) terminals and cuneothalamic relay neurons (CTNs) in the rat cuneate nucleus were found to form axosomatic, axodendritic and axospinous synapses. With these procedures, immunogold-labelled glycine-IR terminals were medium-sized (mean area= 1.670.7 mm2). Our results suggest that glycine might be one of the important inhibitory neurotransmitters in the cuneate nucleus.