Ultrastructure and Metallothionein Expression in Rat Liver Treated with Di-(2-ethylhexyl)phthalate

Di-(2-ethylhexyl)phthalate에 의한 흰쥐 간세포 미세구조와 metallothionein 발현에 미치는 영향

  • Kim, Da-Ham (Department of Biology, Soonchunhyang University) ;
  • Moon, Seung-Hoon (Department of Biology, Soonchunhyang University) ;
  • Lee, Mi-Young (Department of Medical Biotechnology, Soonchunhyang University) ;
  • Lee, Jong-Hwa (Department of Environmental Health Science, Soonchunhyang University) ;
  • Park, Young-Hyun (Department of Food Science and Nutrition, Soonchunhyang University) ;
  • Shin, Kil-Sang (Department of Biology, Soonchunhyang University) ;
  • Kim, Wan-Jong (Department of Biology, Soonchunhyang University)
  • 김다함 (순천향대학교 생명과학과) ;
  • 문승훈 (순천향대학교 생명과학과) ;
  • 이미영 (순천향대학교 의료생명공학과) ;
  • 이종화 (순천향대학교 환경보건학과) ;
  • 박영현 (순천향대학교 식품영양학과) ;
  • 신길상 (순천향대학교 생명과학과) ;
  • 김완종 (순천향대학교 생명과학과)
  • Published : 2007.11.30

Abstract

Di-(ethyhexyl) phthalate (DEHP), commonly used as a plasticizer for manufacturing flexible vinyl products, has been the topic of extensive research, especially concerning endocrine disrupting properties. Metallothionein (MT) is a low molecular weight (6,000$\sim$7,000 Da), cysteine-rich (22$\sim$23%), metal-binding protein and is known to be induced by extrinsic factors such as chemical agents and stresses. Some of the known function of MT include detoxification of heavy metals and alkylating agents and neutralization of free radicals. Nonetheless, the definitive physiological function of MT are still unknown. This study was carried out to investigate the effects of DEHP on the ultrastructural changes and the expression of MT of the rat liver. The rats were orally intubated with either corn oil (experimental control) or 0.5 mg, 1.5 mg and 4.5 mg DEHP kg$^{-1}$ day$^{-1}$ in 0.5 mL of corn oil for 15 days before sacrificing and sampling. DEHP induced mild ultrastrctural changes of some cell organelles such as rough endoplasmic reticulum, mitochondria, lysosomes and peroxisomes in the rat liver treated with DEHP. In the respect of immunogold labelling and Western blotting, MT expression of the liver tissue was up-regulated by DEHP. In conclusion, DEHP has effects on the ultrastructures and hepatic function for MT expression in rat.

본 연구에서는 내분비계 장애물질으로 알려져 있고, 플라스틱 제품의 가소제로 사용되고 있는 di-(2-ethylhexyl) phthalate (DEHP)가 흰쥐의 간세포 미세구조와 간조직내 metallothionein (MT)의 발현 양상에 미치는 영향을 조사하였다. DEHP는 흰쥐 간세포의 미세구조와 MT 발현에 영향을 주었다. 실험군의 경우 조면소포체가 발달하고, 미토콘드리아가 증가하며 리소솜 혹은 퍼옥시좀들이 증가하는 경향을 나타냈다. 한편, MT 발현의 변화를 면역세포 화학적 방법과 western Blot을 수행한 결과 저농도 투여군에서는 약 1.5배, 고농도 투여군에서는 약 2배 가량 증가하는 결과를 나타냈다. 결론적으로 DEHP는 흰쥐 간세포의 구조와 기능에 영향을 주는 것으로 판단되며, 이러한 세포내 스트레스가 MT 발현 증가 현상과 연관이 있을 것으로 판단된다.

Keywords

References

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