Choi E H, Ahn S K, Lee S H
Department of Dermatology, Yonsei University Wonju College of Medicine, Korea.
Exp Dermatol. 1997 Feb;6(1):29-35. doi: 10.1111/j.1600-0625.1997.tb00142.x.
Abnormal follicular keratinization is important for comedo formation in acne, but the precise mechanism is not known. A recent report about acne vulgaris suggested that an impaired water barrier function may be responsible for comedo formation, since the barrier dysfunction is accompanied by hyperkeratosis of the follicular epithelium. Furthermore, the integrity of the water barrier is crucial for the maintenance of the epidermal calcium gradient. Yet stratum corneum intercellular lipid structures, a major factor of the skin barrier function, and calcium distribution in the follicular epithelium of comedones, were not reported. To see SC intercellular lipid and calcium distribution of the follicular epithelium of comedo by electron microscopy, we applied oleic acid on the inner surface of the ear of New Zealand white rabbits to induce comedones, and then we obtained specimens and performed osmium and ruthenium tetroxide postfixation and calcium ion-capture cytochemical procedure. We found incomplete lipid bilayer structures, prominent dilatation of lacunar domains and the loss of follicular epidermal calcium gradient in experimentally induced comedones. From our results, we suggest that the permeability barrier disruption in oleic-acid-applied follicular epithelium can be induced by the changes of SC intercellular membrane structures and lacunar dilatation, and the calcium gradient is lost, so follicular epithelial proliferation and hyperkeratosis can be induced and then comedo formation occurs.
异常的毛囊角化对痤疮中粉刺的形成很重要，但确切机制尚不清楚。最近一篇关于寻常痤疮的报告表明，水屏障功能受损可能是粉刺形成的原因，因为屏障功能障碍伴随着毛囊上皮的角化过度。此外，水屏障的完整性对于维持表皮钙梯度至关重要。然而，角质层细胞间脂质结构（皮肤屏障功能的一个主要因素）以及粉刺毛囊上皮中的钙分布情况尚未见报道。为了通过电子显微镜观察粉刺毛囊上皮的角质层细胞间脂质和钙分布，我们在新西兰白兔耳朵内表面涂抹油酸以诱导粉刺形成，然后获取标本并进行锇和四氧化钌后固定以及钙离子捕获细胞化学程序。我们发现在实验诱导的粉刺中存在不完全的脂质双层结构、腔隙区域明显扩张以及毛囊表皮钙梯度丧失。根据我们的结果，我们认为涂抹油酸的毛囊上皮中的通透性屏障破坏可能是由角质层细胞间膜结构的变化和腔隙扩张引起的，并且钙梯度丧失，从而可诱导毛囊上皮增殖和角化过度，进而发生粉刺形成。
