Applied Microscopy

Korean Society of Microscopy (한국현미경학회)
권호 표지

Immunogold Labellings and Expression of Metallothionein in Regenerating Rat Liver

재생중인 흰쥐 간의 메탈로사이오닌에 대한 면역-금 표지 및 발현에 관한 연구

  • Ahn, Young-Mo (Dept. of Life Science, College of Natural Science, Soonchunhyang University) ;
  • Oh, Seung-Han (Dept. of Life Science, College of Natural Science, Soonchunhyang University) ;
  • Kim, Ho-Jin (Dept. of Life Science, College of Natural Science, Soonchunhyang University) ;
  • Lee, Mi-Young (Dept. of Life Science, College of Natural Science, Soonchunhyang University) ;
  • Lee, Jong-Hwa (Dept. of Environmental Health Science, College of Natural Sciences, Soonchunhyang University) ;
  • Shin, Kil-Sang (Dept. of Life Science, College of Natural Science, Soonchunhyang University) ;
  • Kim, Wan-Jong (Dept. of Life Science, Soonchunhyang University)
  • 안영모 (순천향대학교 자연과학대학 생명과학부) ;
  • 오승한 (순천향대학교 자연과학대학 생명과학부) ;
  • 김호진 (순천향대학교 자연과학대학 생명과학부) ;
  • 이미영 (순천향대학교 자연과학대학 생명과학부) ;
  • 이종화 (순천향대학교 자연과학대학 환경보건학과) ;
  • 신길상 (순천향대학교 자연과학대학 생명과학부) ;
  • 김완종 (순천향대학교 자연과학대학 생명과학부)
  • Published : 2005.03.01
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Abstract

Metallothionein (MT) is a low molecular weight, cysteine-rich, metal-binding, and non-enzymatic protein. The present study was carried out to investigate the expression of MT gene as well as the localization of MT in regenerating rat liver. In partial hepatectomized rats, MT mRNA was detected as early as 1 hr and reached a maximal level by 8 hr after the operation. Thereafter, this level decreased gradually until 24 hr, and it became similar to that of sham control. Meanwhile, time course of MT immunoreactivity using immunogold-labelling revealed that the number of gold particles in hepatocytes increased significantly by 12 hr, but decreased at 48 hr after partial hepatectomy. Ultrastructurally, immunogold particles indicating the presence of MT were distributed in both the cytoplasm and the nucleus of the rat hepatocytes, particularly the particles were distributed at rough endoplasmic reticulum and nucleolus and did not seem to adhere to mitochondria or lysosomes in proliferating hepatocytes. Briefly, high level of MT mRNA expression and the intense immunoreactivity and/or the specific localization of MT was observed during liver regeneration. These results suggest that MT possibly involves hepatocyte proliferation via the storage or the supply of various metal ions in the regenerating rat liver.

진핵세포 내에 존재하는 metallothionein (MT)은 시스테인 함량이 높은 저분자량의 단백질로서 2가 금속이온들과의 친화력이 높아 중금속에 대한 해독작용, 금속이온의 대사 및 세포분열 등과 관련되어 있다. 본 연구자들은 간 재생능력이 우수한 흰쥐를 실험모델로 하여, 간의 70% 정도를 실험적으로 제거한 후, 간 재생을 유도하는 과정에서 시간 경과에 따라 간세포의 미세구조 변화와 더불어 MT 유전자 발현 및 이 단백질의 세포내 분포를 알아보고자 하였다. 부분 간 절제 후 간 조직이 증식되고 재구성되어 간이 원래의 크기로 재생되는 시간은 1주일 정도가 소요되었다. 재생중인 간세포는 핵대 세포질의 비가 크고, 핵내에 인이 크게 발달하고 크기가 작은 미토콘드리아가 다수 나타났으며, 조면소포체가 잘 발달하고 있었다. MT mRNA는 간 절제 직후부터 증가하기 시작하여 1시간 경과 후에 최대치에 이르렀고, 12시간 이후부터 감소하기 시작하였다. 재생중인 간세포에서 MT에 대한 면역반응은 간 절제 후 12시간이 경과한 군에서 가장 높게 나타났고, 이후 점차 감소하여 8일이 경과한 실험군에서는 정상 대조군과 유사한 정도로 감소하는 것으로 관찰되었다. 또한, 간 재생 초기에는 항-MT 금 입자들이 주로 세포질쪽에 분포하다가 점차 핵내에 존재하는 양이 증가하는 것으로 나타났다. 이러한 결과들은 간 절제 후 보상작용으로 일어나는 세포분열 단계에서 MT가 이 과정에 필요한 요소를 제공하는 역할을 수행하기 때문인 것으로 사료된다.

Keywords

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