Abstract: In order to study the relationship between endothelin and psoriasis, we determined the plasma levels of endothelin with the method of radioimmunoassay in 54 patients with psoriasis in comparison with 32 normal subjects. Among the cases of psoriasis, 45 were psoriasis vulgaris (32 in progressive stage and 13 in stable stage) while 9 were erythrodermic psoriasis. The results showed that the level of plasma endothelin in normal controls was 43.5±15.71pg/ml, while the value of psoriatics was 62.01±21.15 pg/ml. The latter was significantly higher than the former (P<0.01). The level of plasma endothelin in erythrodermic psoriasis was higher than that of psoriasis vulgaris(P<0.05). In psoriasis vulgaris, the plasma levels of endothelin between progressive stage and stable stage were not significantly different. The above mentioned data suggest that endothelin may have a role in the pathogenesis of psoriasis. It is deemed that further study on the mechanism of action of this substance may be helpful in developing reasonable treatment for psoriasis.

Key words: Psoriasis, Endothelin