Kligman L H, Akin F J, Kligman A M
J Invest Dermatol. 1982 Feb;78(2):181-9. doi: 10.1111/1523-1747.ep12506359.
To assess the ability of sunscreens to protect connective tissue from actinic damage, hairless mice were irradiated with Westinghouse FS20 sunlamps thrice weekly for 30 weeks. Each exposure, consisting mainly of UV-B and the less energetic UV-A, was approximately 6 human minimal erythema doses under these lights. One group of animals received irradiation only. The other 2 groups were treated, prior to irradiation, with sunscreens of either low or high sun protection factors (SPF 2 and SPF 15, respectively). Skin biopsies were taken at 10-week intervals and were stained with various histochemical stains to reveal changes in the dermis. The unprotected, irradiated animals showed a great increase in the following: reticulin fibers, elastic fibers to the extent of elastosis, neutral and acid mucopolysaccharides and melanin production. The SPF 15 sunscreen completely prevented these changes. The SPF 2 sunscreen was less effective. These effects were substantiated by ultrastructural examination of the tissues by electron microscopy. A surprising histologic finding was the repair capability of the dermis in the post-irradiation period.
为评估防晒霜保护结缔组织免受光化损伤的能力，对无毛小鼠每周用西屋FS20太阳灯照射三次，持续30周。每次照射主要由UV - B和能量较低的UV - A组成，在这些灯光下约为6个人类最小红斑剂量。一组动物仅接受照射。另外两组在照射前分别用低或高防晒系数（分别为SPF 2和SPF 15）的防晒霜处理。每隔10周进行皮肤活检，并用各种组织化学染色剂染色以揭示真皮的变化。未受保护的照射动物在以下方面有大幅增加：网状纤维、弹性纤维出现弹性组织变性、中性和酸性粘多糖以及黑色素生成。SPF 15的防晒霜完全阻止了这些变化。SPF 2的防晒霜效果较差。通过电子显微镜对组织进行超微结构检查证实了这些效果。一个令人惊讶的组织学发现是真皮在照射后阶段的修复能力。
