Effect of 8-methoxypsoralen plus long-wave ultraviolet (PUVA) radiation on mast cells. II. In vitro PUVA inhibits degranulation of rat peritoneal mast cells induced by compound 48/80.
Rat peritoneal mast cells incubated with a histamine liberator, compound 48/80, showed a significantly reduced capacity for releasing histamine following in vitro treatment with 0.1 micrograms/ml of 8-methoxypsoralen (8-MOP) plus 1-5 J/cm2 of long-wave ultraviolet (UVA) irradiation (PUVA). No remarkable inhibition in histamine release was observed in the cells treated with 8-MOP only. Irradiation with 5 J/cm2 of UVA alone exerted an inhibitory effect on histamine release, to a lesser extent than PUVA. PUVA irradiation did not bring any decrease in cell viability or any spontaneous release of histamine from irradiated cells as shown by phase-contrast microscopy and by histamine assay, respectively. These results suggest that PUVA treatment may cause a noncytotoxic disturbance at mast cell membranes or on surface receptors, leading to a decreased capacity for secreting chemical mediators.
D000818:Animals; D003594:Cytoplasmic Granules / Q000187:drug effects* / Q000528:radiation effects; D006636:Histamine Release / Q000187:drug effects / Q000528:radiation effects; D066298:In Vitro Techniques; D008297:Male; D008407:Mast Cells / Q000187:drug effects* / Q000528:radiation effects; D008858:Microscopy, Phase-Contrast; D011701:PUVA Therapy; D051381:Rats; D011919:Rats, Inbred Strains; D003189:p-Methoxy-N-methylphenethylamine / Q000037:antagonists & inhibitors*
D003189:p-Methoxy-N-methylphenethylamine