A Study on the Changes of the Synaptic Structures in the Interpolar Part of Spinal Trigeminal Nucleus of Rat during Aging

연령증가에 따른 흰쥐 삼차신경척수핵 중간부분에서의 신경연접구조의 변화에 관한 연구

  • Kim, Myung-Kook (Departments of Oral Anatomy and College of Dentistry, Seoul National University) ;
  • Kim, Cheol-We (Dental Biomaterials, College of Dentistry, Seoul National University) ;
  • Paik, Ki-Suk (Departments of Oral Anatomy and College of Dentistry, Seoul National University) ;
  • Lim, Bum-Soon (Dental Biomaterials, College of Dentistry, Seoul National University)
  • 김명국 (서울대학교 치과대학 구강해부학교실) ;
  • 김철위 (서울대학교 치과대학 치과생체재료학교실) ;
  • 백기석 (서울대학교 치과대학 구강해부학교실) ;
  • 임범순 (서울대학교 치과대학 치과생체재료학교실)
  • Published : 1998.09.01

Abstract

This study was performed to observe the morphological changes of the synaptic structures in the interpolar part of the spinal trigeminal nucleus of rat during aging. Transmission electron microscopy has been used to determine the r)umber of synapses, length of postsynaptic densities, number and area of axon terminals. Sprague-Dawley rat 3, 12, 24 and 36 months of age were used in this study. 1. The number of synapses was 51.7, 43.1, 28.4 and 16.8 in the 3, 12, 24 and 36 months of age respectively. Therefore, the number of synapses decreased gradually with age, but decreased significantly in the 24 and 36 months. 2. The length of postsynaptic densities was $30.2{\mu}m,\;23.6{\mu}m,\;10.4{\mu}m\;and\;4.9{\mu}m$ in the 3, 12, 24 and 36 months of age respectively. Therefore, the length of postsynaptic densities decreased gradually with age, but decreased significantly in the 24 and 36months. 3. The number of axon terminals was 84.3, 73.7, 51.4 and 26.6 in the 3, 12, 24 and 36 months of age respectively. Therefore, the number of axon terminals decreased gradually with age, but decreased significantly in the 24 and 36months. 4. The area of axon terminals was $76.1{\mu}m^2,\;64.1{\mu}m^2,\;29.9{\mu}m^2\;and\;13.8{\mu}m^2$ in the 3, 12, 24 and 36 months of age respectively. Therefore, the area of axon terminals decreased gradilally with age, but decreased significantly in the 24 and 36 months. The results suggest that there are the changes of the synaptic structures in the interpolar part of spinal trigeminal nucleus of rat during aging. These changes nay be concerned to the decreased function of mediating pain and temperature sensation in the face and oral cavity during aging.

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