Fritsch P O
Department of Dermatology, University of Innsbruck Medical School.
J Am Acad Dermatol. 1992 Dec;27(6 Pt 2):S8-14. doi: 10.1016/s0190-9622(08)80253-8.
Synthetic retinoids, particularly the aromatic retinoid etretinate (Tigason, Europe; Tegison, United States), have had an established role in the treatment of psoriasis and a variety of ichthyosiform disorders for more than a decade. Isotretinoin (Accutane), which was released at approximately the same time, plays a less important role in these disorders. The mechanism of action of etretinate is still incompletely understood although, like retinoic acid, it is thought to interfere with the terminal differentiation of keratinocytes. The recent detection of nuclear retinoic acid receptors may lead to a unifying theory of retinoid effects and provide the means for more targeted use of this class of compounds. The substantial amount of data on the clinical effectiveness of etretinate was obtained empirically from numerous multicenter trials and individual reports; its indications, dosimetry, pharmacokinetics, and side effects are well established. The main adverse effect associated with etretinate is its teratogenicity (common to all retinoids), which is of particular concern because the lipophilic compound is stored in fat tissue, resulting in an elimination half-life of as many as 120 days. To avoid this problem the much less lipophilic unesterified acid of etretinate, acitretin, has been made available and has now replaced etretinate in many countries. Acitretin represents the active principle of etretinate and has an elimination half-life of 2 days. No significant clinical differences have been observed between these two compounds. Partial in vivo conversion of acitretin into etretinate, however, has been described in some patients. Both compounds are standard treatment for pustular and erythrodermic psoriasis.(ABSTRACT TRUNCATED AT 250 WORDS)
合成维甲酸，尤其是芳香维甲酸依曲替酯（欧洲的Tigason；美国的Tegison），在治疗银屑病和多种鱼鳞病样疾病方面已有超过十年的确立作用。大约同时上市的异维甲酸（Accutane）在这些疾病中的作用较小。依曲替酯的作用机制仍未完全明了，尽管它与维甲酸一样，被认为会干扰角质形成细胞的终末分化。最近发现的核维甲酸受体可能会引出维甲酸作用的统一理论，并为更有针对性地使用这类化合物提供方法。关于依曲替酯临床疗效的大量数据是通过众多多中心试验和个别报告凭经验获得的；其适应证、剂量测定、药代动力学和副作用都已明确。与依曲替酯相关的主要不良反应是其致畸性（所有维甲酸都有），这尤其令人担忧，因为这种亲脂性化合物会储存在脂肪组织中，导致消除半衰期长达120天。为避免这个问题，依曲替酯的亲脂性小得多的未酯化酸阿维A已上市，现在在许多国家已取代了依曲替酯。阿维A是依曲替酯的活性成分，消除半衰期为2天。这两种化合物之间未观察到显著的临床差异。然而，在一些患者中已描述了阿维A在体内部分转化为依曲替酯的情况。这两种化合物都是脓疱型和红皮病型银屑病的标准治疗药物。（摘要截短于250字）
