Vitamin A and beta-carotene concentrations at different depths of the epidermis: a preliminary study in the cow snout.
Vitamin A and beta-carotene concentrations at different depths of the epidermis: a preliminary study in the cow snout.
复制标题
表皮不同深度的维生素 A 和 β-胡萝卜素浓度：牛口鼻部的初步研究。
DOI：
10.3109/03009738709178695
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发表时间：
1987
影响因子：
3.4
通讯作者：
H. Törmä
中科院分区：
文献类型：
--
作者：
A. Vahlquist;E. Stenström;H. Törmä
维生素A（视黄醇）是正常上皮分化所必需的抗角化剂。为了研究维生素A和维生素A原（β -胡萝卜素）的表皮分布，我们利用了牛非常厚的鼻子表皮，它可以水平切成至少6层，代表不同成熟阶段的角化细胞。皂化样品提取液采用反相高效液相色谱法分析视黄醇和β -胡萝卜素。视黄醇浓度最高（0.8微克/克蛋白质，n = 3）记录在真皮附近；在表皮上部发现视黄醇的含量逐渐减少。β -胡萝卜素在表皮下部含量最高（1.0微克/克，n = 7）；在真皮过渡区和表皮上部可见明显较低的水平。结果表明，鼻部表皮内源性维生素A浓度与细胞分化程度呈负相关。
Vitamin A (retinol) is an anti-keratinizing agent essential for normal epithelial differentiation. In order to examine the epidermal distribution of vitamin A and provitamin A (beta-carotene), we took advantage of the extraordinarily thick snout epidermis of the cow which can be cut horizontally into at least 6 layers, representing keratinocytes at different stages of maturation. Extracts of saponified samples were analyzed for retinol and beta-carotene by reversed phase high-performance liquid chromatography. The highest retinol concentration (0.8 micrograms/g protein; n = 3) was recorded closest to the dermis; progressively decreasing amounts of retinol were found in the upper parts of epidermis. Maximum values of beta-carotene (1.0 micrograms/g; n = 7) were found in the lower parts of epidermis; substantially lower levels were seen at the dermal transition zone and in the upper parts of epidermis. The results suggest that the endogenous concentration of vitamin A in snout epidermis is inversely related to the degree of cellular differentiation.