Rong Yan-Hua, Zhang Gun-An, Wang Cheng, Ning Fang-Gang
Department of Burns, JiShuiTan Hospital, Beijing 100035, PR China.
Zhonghua Shao Shang Za Zhi. 2008 Feb;24(1):51-3.
To quantify the content of type I, III collagen and their ratio in normal human skin of different age, and to explore the regulation of changes.
The normal human skin specimens were obtained from 6 spontaneously aborted fetus and 56 burn patients of different ages, including infants (newborn -3 years), pre-school group ( > 3, < or =7 years), adolescent group ( >7, < or = 18 years), youth and middle age group ( > 18, < or = 50 years), and elderly group ( > 50 years), were studied. The total collagen content were determined by hydroxyproline method. The contents of type I, Ill collagen and their ratio were examined by immunohistochemistry.
The total collagen content decreased along with increase in age, and it was highest in fetus [(543 +/- 13) microg/g]. The ratio between type I and Ill collagen increased along with increase in age. The content of type III collagen was highest in fetus [(278 +/- 7) microg/g], and it decreased along with increase in age. The content of type I collagen content was [(265 +/- 7) microg/g] in fetus, and it was increased slightly in infant and pre-school groups, then decreased along with advance in age.
Decomposition of type III collagen in normal human skin may exceed its synthesis after birth immediately, leading to its reduction. Synthesis of type I collagen in normal human skin is dominant before 8 years old, and it shows an opposite tendency afterwards.
定量分析不同年龄段正常人皮肤中I型、III型胶原蛋白的含量及其比例，并探讨其变化规律。
选取6例自然流产胎儿及56例不同年龄段烧伤患者的正常皮肤标本进行研究，包括婴儿（新生儿-3岁）、学龄前组（>3岁，≤7岁）、青少年组（>7岁，≤18岁）、中青年组（>18岁，≤50岁）和老年组（>50岁）。采用羟脯氨酸法测定总胶原蛋白含量，免疫组织化学法检测I型、III型胶原蛋白含量及其比例。
总胶原蛋白含量随年龄增长而降低，胎儿期最高[（543±13）μg/g]。I型与III型胶原蛋白的比例随年龄增长而增加。III型胶原蛋白含量在胎儿期最高[（278±7）μg/g]，并随年龄增长而降低。I型胶原蛋白含量在胎儿期为[（265±7）μg/g]，在婴儿和学龄前组略有增加，随后随年龄增长而降低。
出生后正常人皮肤中III型胶原蛋白的分解可能立即超过其合成，导致其含量降低。正常人皮肤中I型胶原蛋白的合成在8岁前占主导地位，之后呈相反趋势。
