사염화탄소 간 손상후 생기는 세포외기질의 분포 및 세포기원

Abstract

[한글]

간은 급성이나 만성적인 손상이 있을때 원인에 관계없이 많은 세포외기질이 축적되어 정상 구조가 변형되고 섬유조직으로 변하여 간경변증이 된다. 일반적으로 교원섬유는 섬유아세포나 섬유아세포의 전구체에서만 합성 분비되는 것으로 알려져 있는데, 정상 간의

Disse 강 내에는 섬유아세포가 없고 세포배양 실험에서 간 세포와 동양구조내의 비실질세포에서 모두 교원섬유를 합성할 수 있어서 간의 세포외기질을 만드는 세포기원에 대하여 많은 논란이 있다. 이에 저자는 간에 만성적인 손상을 주었을때 축적되는 세포외기질의

분포와 축적과정, 지방저장세포의 증식역동을 통해서 간 섬유화의 세포기원을 알아 보고자 하였다. 실험동물로는 암컷 흰쥐를 사용하였으며 사염화탄소를 장기간 투여하여 만성 손상을 유발하였다. 형태학적인 변화는 H-E 염색, Masson's trichrome 염색, methenamine

silver 염색, 세포외기질에 대한 Ⅲ형 교원섬유, Ⅳ형 교원섬유, fibronectin, laminin 면역조직화학염색과 지방저장세포에 대한 desmin 면역조직화학염색으로 관찰하여 다음과 같은 결과를 얻었다.

1. Methenamine silver 양성섬유는 대조군과 지방변성기에 동양구조벽에서 불연속적으로 관찰되었고, 섬유격막기와 간경변증기의 재생결절에는 적거나 거의 없었다.

2. 세포외기질의 성분별 출현시기는 fibronectin, Ⅳ형 교원.섬유, Ⅲ형 교원섬유, laminin 순이었다.

3. Fibronectin과 Ⅳ형 교원섬유는 대조군과 모든 실험군의 동양구조벽에서 표현되었으며, 섬유격막기와 간경변증기에 더욱 뚜렸하였다.

4. Ⅲ형 교원섬유와 laminin은 섬유격막기의 동양구조벽에 불연속적인 선모양으로 출현하기 시작하여 간경변증기에는 연속적인 선으로 나타났다.

5. 간문맥과 섬유격막기 및 간경변증기의 섬유격막에서 모든 성분의 세포외기질이 관찰되나 Ⅳ형 교원섬유 및 laminin은 담관이나 혈관주위에 좀 더 많았다.

6. 섬유격막기와 간경변증기에는 Disse 강 내 지방저장세포의 수가 감소하면서 섬유격막내에 급격히 증가하였다.

7. 지방저장세포에서는 Ⅳ형 교원섬유와 laminin이 표현되었다.

이상의 소견을 종합하면 섬유격막의 세포외기질의 생성에 지방저장세포의 역할이 중요한것으로 생각되며, 소엽내 세포외기질생성에는 지방저장세포 이외의 간세포나 혈관내피 세포도 관여할 것으로 사료된다.

Distribution and cellular origin of hepatic extracellular matrix following carbon

tetrachloride liver injury in rat

Eun Kyung Han

Department of Medical Science The Graduate School, Yonsei University

(Directed by Professor Chanil Park)

Hepatic extracellular matrix(ECM) increases in various acute and chronic liver

diseases. Recent investigations attempted to clarify structures and suctions of the

hepatic extracellular matrix, however, the cellular origin of the various ECM

remains uncertain. We studied the CCl^^4 -induced hepatic fibrosis of rat to

investigate the distribution pattern of ECM, using methenamine silver stain and

immunohistochemical stains for laminin, fibronectin and collagen types Ⅲ and Ⅳ.

Immunohistochemical stain for desmin was also done to find out the fat-storing

cells which had been known to be the important source of hepatic collagen type Ⅰ.

The results were as follows:

1. In normal rat and in the fatty metamorphosis stave of liver injury,

discontinuous linear deposition of methenamine silver positive material was found

in the sinusoidal wall. In contrast no such material was present in the stages of

septal fibrosis and cirrhosis.

2. Fibronectin arose first in the space of Disse followed by collagen type Ⅳ,

collagen type Ⅲ and laminin in the order of appearance.

3. Fibronectin and type Ⅲ collagen were expressed in the sinusoidal wall of all

stages of liver iniury, although more prominent in the septal fibrosis and

cirrhosis stages.

4. Collagen type Ⅲ and laminin appeared as a discontinuous layer along the

sinusoidal wall of the septal fibrosis stage but became a continuous layer in the

cirrhosis stage.

5. Portal tracts and fibrous septa at the septal fibrosis and cirrhosis stages

contained all components of ECM. Collagen type Ⅳ and laminin were more prominent

around the vessels and bile ducts.

6. The number of fat-storing cells was decreased in the space of Disse, but

significantly increased at the fibrous septa in the stages of septal fibrosis and

cirrhosis.

7. Occasional fat-storing cells expressed collagen type Ⅳ and laminin in the

their cytoplasm.

In conclusion, it is suggested that the fat-storing cell plays the pivot role in

the formation of hepatic ECM including laminin and collagen type Ⅳ, and the

findings that deposition of ECM continues to increase in spite of the decrease of

fat-storing cell number in the hepatic lobule suggest that hepatocytes and

endothelial cells may also play some role in the formation of intralobular ECM.

[영문]

Hepatic extracellular matrix(ECM) increases in various acute and chronic liver diseases. Recent investigations attempted to clarify structures and suctions of the hepatic extracellular matrix, however, the cellular origin of the various ECM

remains uncertain. We studied the CCl^^4 -induced hepatic fibrosis of rat to investigate the distribution pattern of ECM, using methenamine silver stain and immunohistochemical stains for laminin, fibronectin and collagen types Ⅲ and Ⅳ.

Immunohistochemical stain for desmin was also done to find out the fat-storing cells which had been known to be the important source of hepatic collagen type Ⅰ.

The results were as follows:

1. In normal rat and in the fatty metamorphosis stave of liver injury, discontinuous linear deposition of methenamine silver positive material was found in the sinusoidal wall. In contrast no such material was present in the stages of septal fibrosis and cirrhosis.

2. Fibronectin arose first in the space of Disse followed by collagen type Ⅳ, collagen type Ⅲ and laminin in the order of appearance.

3. Fibronectin and type Ⅲ collagen were expressed in the sinusoidal wall of all stages of liver iniury, although more prominent in the septal fibrosis and cirrhosis stages.

4. Collagen type Ⅲ and laminin appeared as a discontinuous layer along the sinusoidal wall of the septal fibrosis stage but became a continuous layer in the cirrhosis stage.

5. Portal tracts and fibrous septa at the septal fibrosis and cirrhosis stages contained all components of ECM. Collagen type Ⅳ and laminin were more prominent around the vessels and bile ducts.

6. The number of fat-storing cells was decreased in the space of Disse, but significantly increased at the fibrous septa in the stages of septal fibrosis and cirrhosis.

7. Occasional fat-storing cells expressed collagen type Ⅳ and laminin in the their cytoplasm.

In conclusion, it is suggested that the fat-storing cell plays the pivot role in the formation of hepatic ECM including laminin and collagen type Ⅳ, and the findings that deposition of ECM continues to increase in spite of the decrease of fat-storing cell number in the hepatic lobule suggest that hepatocytes and

endothelial cells may also play some role in the formation of intralobular ECM.