Hirayama H, Okuyama T, Furuya H
Nihon Sanka Fujinka Gakkai Zasshi. 1982 Nov;34(11):1839-45.
The aim of this study is to investigate the roles and characteristics of the collagen in the human placenta during pregnancy, measuring it's hydroxyproline contents, solubility of collagen and prolyl hydroxylase activity. The results obtained were as follow: 1) Hydroxyproline contents in the placenta of 1st, 2nd and 3rd trimester were 0.41, 1.38 and 2.17mg/g wet weight respectively. Significant difference was found between the levels in the 1st and the 3rd trimester (p less than 0.01). 2) During the course of pregnancy no significant proportional change in acid-soluble fraction of the collagen, and proportional increase in pepsin-soluble fraction and decrease in insoluble fraction of the collagen were found. 3) Prolyl hydroxylase activity in the placenta of 1st, 2nd and 3rd trimester were 1058.5, 326.2 and 248.4 C.P.M./mg protein respectively. Prolyl hydroxylase activity was found to be higher in the 1st trimester than that in later trimesters (p less than 0.05). It's suggested that the collagen would take part in developmental construction of the placenta from the results obtained, which showed significant changes during the course of pregnancy in it's content and nature and available enzyme for it's synthetic process.
