Problems of Radiation Medicine and Radiobiology

Radiation,induced changes in connective tissue matrix of rat organs at total body X-ray exposure

N. E. Uzlenkova
State Institution “S.P. Grigoriev Institute for Medical Radiology of the National Academy of MedicalSciences of Ukraine”, Pushkins'ka str, 82, Kharkiv, 61024, Ukraine

Objective. To study the nature of radiation-induced changes in the connective tissue matrix of rats under single total body X-ray exposure in minimal lethal and sublethal doses.
Materials and methods. Experiments conducted on white male rats weighing 160–180 g, which were exposed to the influence of X-radiation doses LD15/30 and LD60/30 at the installation RUM-17 in standard specifications.
Assessment of connective tissue matrix was performed by the total content of collagen, soluble (SC) and insoluble (ISC) collagen, collagen destruction rate by free hydroxyproline, collagenlytic activity (CLA), individual glycosaminoglycans (GAG). Experiments were performed on days 3, 7 and 14 and 30th, 90th and 180th days. The age control was used to each term of experiments. Statistical analysis of data was performed using Wilcoxon-Mann-Whitney criterion and Student's t-test using packet Biostatistics v.4.03 for Windows.
Results. The changes of collagen (3–7 days) were characterized by violation of ratio SC and ISC, accelerated disintegration of collagen by free hydroxyproline in the lungs – 1.7 times, the skin – 1.2 times, rising of metal-depending CLA in the lungs – 2.0 times and metal-independing CLA in the skin – 2.2 times, an increase of hyaluronic acid in the lungs – 1.7 times, in the skin – 1.5 times. At the late period (180 days) an increase of the total content of collagen was determined with a 1.4 times predominance of IC in the lungs and 1.3 times in the skin. During this period changes of individual GAG were characterized by – 1.7 times increase of chondroitin sulfate A and C in the lungs, 1.6 times dermatan sulfate in the skin and 1.7 times heparan sulfate in both organs.
Conclusion. Revealed radiation-induced changes in the connective tissue matrix of rats in their direction were not dependent on the dose of X-rays, were organ-specific and determined by time after exposure.

Key words: external X-ray irradiation, lung, skin, connective tissue matrix, rats.

Problems of radiation medicine and radiobiology. 2014;19:471-481.