Danno K, Fujii K, Tachibana T, Toda K, Horio T
Department of Dermatology, Faculty of Medicine, Kyoto University, Japan.
J Invest Dermatol. 1988 Jun;90(6):806-9. doi: 10.1111/1523-1747.ep12462027.
This study was designed to investigate the effect of ultraviolet B (UVB) irradiation on mast cell functions. Purified mast cells obtained from rat peritoneal cavity were irradiated with UVB and subsequently exposed to a degranulator, compound 48/80, or the calcium ionophore A-23187. The amount of histamine released from mast cells measured by the enzyme isotopic assay was significantly decreased by UVB irradiation (100-400 mJ/cm2). Within this dose range, UVB alone was not cytotoxic to the cells because it did not induce histamine release. The suppression was observed when mast cells were subjected to degranulation without intervals after UVB irradiation, and even after 5 h postirradiation. The wavelength of 300 nm from a monochromatic light source showed the maximum effect. When mast cells prelabeled with [3H]arachidonate were irradiated and challenged by compound 48/80, label accumulation in diacylglycerol produced by the phosphatidylinositol cycle was considerably decreased by UVB irradiation. From these results, we hypothesize that, within an adequate irradiation dose, UVB irradiation suppresses histamine release from mast cells, probably by causing noncytotoxic damage to the membrane phospholipid metabolism, which is tied to the degranulation mechanisms.
本研究旨在探讨中波紫外线（UVB）照射对肥大细胞功能的影响。从大鼠腹腔获得的纯化肥大细胞经UVB照射，随后暴露于脱颗粒剂化合物48/80或钙离子载体A-23187。通过酶同位素分析法测定，UVB照射（100 - 400 mJ/cm2）可使肥大细胞释放的组胺量显著减少。在此剂量范围内，单独的UVB对细胞无细胞毒性，因为它不会诱导组胺释放。当肥大细胞在UVB照射后无间隔地进行脱颗粒时，甚至在照射后5小时，均观察到抑制作用。来自单色光源的300 nm波长显示出最大效应。当用[3H]花生四烯酸预标记的肥大细胞经照射并受到化合物48/80刺激时，UVB照射可使磷脂酰肌醇循环产生的二酰甘油中的标记物积累显著减少。根据这些结果，我们推测，在适当的照射剂量范围内，UVB照射可能通过对与脱颗粒机制相关的膜磷脂代谢造成非细胞毒性损伤，从而抑制肥大细胞释放组胺。
