[Psoralen sensitized thermoactivated photodamage to leukocyte membranes]

Psoralen sensitized photodamage of rat peritoneal exudate cells was investigated. Irradiation of cells induced latent lesions in membranes which during thermal activation at the post-irradiation stage were transformed into permeability channels for trypan blue. The effect linearly increased with fluence of irradiation which indicates one hit production of thermolabile psoralen photoproducts in the membranes.