Freinkel R K, Wier K A
J Invest Dermatol. 1975 Dec;65(6):482-7. doi: 10.1111/1523-1747.ep12610193.
Synthesis of epidermal proteins has been assessed during epidermal differentiation in fetal rat skin by studies of the simultaneous incorporation of [14C]histidine (H) and [3H]leucine (L) in vitro. Relative incorporation of the two amino acids into epidermal proteins was assessed in terms of H/L ratios and absolute rates of incorporation related to DNA content. Biochemical parameters were correlated with morphologic development. An increase in incorporation of both amino acids accompanied stratification and development of granular and cornified layers between 18 days of gestation and 3 to 5 days postpartum. Relatively greater incorporation of histidine after development of mature granular cells and stratum corneum was reflected in increasing H/L ratios. These results correlated with negative Pauly staining of the initial fetal keratohyaline granules at day 18 and positive staining of mature granules at subsequent stages of development. H/L ratios appear to represent a sensitive marker for differential protein synthesis during differentiation in whole epidermis. The results suggest that biosynthesis of histidine-rich protein is associated with production of mature keratohyaline granules during fetal development.
通过体外同时掺入[14C]组氨酸（H）和[3H]亮氨酸（L）的研究，对胎鼠皮肤表皮分化过程中表皮蛋白的合成进行了评估。根据H/L比值评估两种氨基酸掺入表皮蛋白的相对情况，并根据与DNA含量相关的掺入绝对速率进行评估。生化参数与形态学发育相关。在妊娠18天至产后3至5天期间，两种氨基酸掺入量的增加伴随着分层以及颗粒层和角质层的发育。成熟颗粒细胞和角质层发育后组氨酸相对更高的掺入量反映在H/L比值的增加上。这些结果与第18天初始胎儿透明角质颗粒的保利染色阴性以及发育后期成熟颗粒的阳性染色相关。H/L比值似乎代表了全表皮分化过程中差异蛋白合成的敏感标志物。结果表明，富含组氨酸蛋白的生物合成与胎儿发育过程中成熟透明角质颗粒的产生有关。
