Korean J Med.  2002 Apr;62(4):453-464.

A study for time sequential expression of IL-1 alphaand IL-6 after irradiation on rat lung

• Chang KY
• Son CH
• Yang DK
• Kim KH
• Lee H
• Youn SM
• Yang KM
• Hur WJ
• Roh MS
• Jeong JS
• Han JY
• Lee KN
• Choi PJ
• Lee SK
• Choi IS
• Park SK

Abstract

BACKGROUND
One of the limitation during the irradiation of malignant tumor is hazard to normal tissue although it is important and effective tool for treating malignant tumor. We studied the role of interleukin-1 alpha (IL-1alpha) and interleukin-6 (IL-6) in the radiation-induced lung injury especially on fibrosis.
METHODS
We irradiated right-side lungs of thirty Sprague-Dawley rats with single fraction of 20 Gy and then sacrificed the animals until 20th week at intervals of two weeks. Both irradiated and unirradiated lung tissues were stained hematoxilin and eosin, Masson trichrome, reticulin and immunohistochemical staining for IL-1alpha and IL-6. The degree of the staining for IL-1alpha and IL-6 were examined semiquantitatively.
RESULTS
Two weeks after irradiation interstitial edema and capillary congestion appeared, followed by increase of the monocytes infiltration and proteinaceous material during 4th and 8th week. After eight weeks of irradiation, collagen and reticulin fibers were detected along alveolar wall. 12th to 20th week, fibrosis in interstitium, decreased number of alveoli and thickening of bronchial wall were observed. The degree of immunohistochemical staining for IL-1alpha and IL-6 was increased rapidly during the first three week and then decreased slowly, but remain incresed until 20th week.
CONCLUSION
Our Study demonstrate the early and persistent elevation of cytokines IL-1alpha and IL-6 by immunohistochemical stain in rat lung following pulmonary irradiation. We think cytokines are produced immediately after irradiation, make collagen genes turn on and perisist until the expression of late effects become apparent pathologically and clinically.

Keyword

Radiation, Pneumonia; Interleukin-1alpha; Interleukin-6

MeSH Terms

Animals
Capillaries
Collagen
Cytokines
Edema
Eosine Yellowish-(YS)
Estrogens, Conjugated (USP)
Fibrosis
Interleukin-1*
Interleukin-1alpha
Interleukin-6*
Lung Injury
Lung*
Monocytes
Rats*
Rats, Sprague-Dawley
Reticulin
Collagen
Cytokines
Eosine Yellowish-(YS)
Estrogens, Conjugated (USP)
Interleukin-1
Interleukin-1alpha
Interleukin-6
Reticulin