Abstract: In order to study the possible role of beta-endorphin (β-EP) in the pathogenesis of psoriasis, serum β-EP was detected by radioimmunoassay in 51 patients with psoriasis and 32 healthy controls. The results showed that serum β-EP level was markedly increased in patients with psoriasis in comparison with healthy controls. The serum β-EP level was reduced when the skin lesions of the patients were cleared after treatment, however, it was still higher than in healthy controls. Although there was a tendency towards an increase of β-EP in patients with precipitating factors in comparison with those without precipitating factors, their levels were not significantly different. There was a negative correlation between the intensity of pruritus and β-EP levels. It is suggested that β-EP involves in the pathogenisis of psoriasis. Its production and release were controlled by the central nervous system and also affected by the inflammation of skin lesions. There might be a causality between β-EP levels and inflammatory reaction of skin lesions.

Key words: Psoriasis, Endorphins