[Animal experiment model of the effect of ultraviolet irradiation on hexachlorobenzene-induced porphyria].

The Effect of UV-Irradiation on the Hexachlorobenzene-induced Porphyria in an Experimental Animal Model Hexachlorobenzene is able to induce in humans and different animal species a hepatic porphyria, which is comparable to porphyria cutanea tarda. We studied whether hexachlorobenzene feeding could induce this porphyria also in hairless rats (Rowett-Nude), as these are suitable for photobiologic studies. After development of hepatic porphyria the rats were irradiated either with UV-A or UV-B light. Biochemical effects on the porphyrin metabolism and clinical as well as histologic skin changes were examined. In the liver of the porphyric rats, UV-A and UV-B irradiation induced increased aminolevulinic acid synthase activity accompanied with augmentation of hepatic porphyrin content. UV-A or UV-B irradiation also lead to increased total porphyrin contents in the skin of porphyric compared to non-irradiated animals. Clinically and histologically, however, only UV-A irradiation induced lesions, which were comparable to skin manifestations of porphyria cutanea tarda.