Eicosanoid Changes in Skin Following Ultraviolet Light Irradiation
The incubation of homogenates prepared from UVB-irradiated guinea pig epidermis (24–72 hr) with [14C]-arachidonic acid ([14C]-AA) resulted in decreased transformation of [14C]-AA into the cyclooxygenase products (PGD2, PGE2, and PGF2α while the incorporation of 14C into lipoxygenase products (15-HETE and 12-HETE) increased. Investigation into the selective inhibition of the cyclooxygenase pathway revealed that the in vitro transformation of [14C]-AA into [14C]-cyclooxygenase products by the 105,000 x g particulate fraction prepared from normal unirradiated guinea pig epidermis was inhibited by the 105,000 x g cytoplasmic extract prepared from a 24-hr postirradiation guinea pig epidermis. These latter data imply (a) that an endogenous inhibitor(s) of the cyclooxygenase pathway is generated and released into the cytoplasm during UVB irradiation and (b) that it is likely that this selective inhibition of the cyclooxygenase pathway may contribute at least in part to the increased lipoxygenase products in the 24-hr postirradiation skin specimens and possibly the recognized prolonged UVB-induced inflammatory process.
KeywordsLipoxygenase Product Cyclooxygenase Pathway Free Arachidonic Acid Cyclooxygenase Product Dihydroxyeicosatetraenoic Acid
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- 4.Blaok, A. K., Greaves, M. W., Hensby, C. N., and Plummer, N. A. Increased Prostaglandins E2 and F2α in human skin at 6 and 24 hours after ultraviolet B irradiation (290-320). Br. J. Clin. Pharmacol. 5: 431–436, 1978.Google Scholar
- 6.Black, A. K., Fincham, N., Greaves, M. W., and Hensby, C. N. Time course changes in levels of arachidonic acid and prostaglandins D2, E2, F2α and 6-OXO-PGF1α in human skin following ultraviolet B irradiation. Br. J. Clin. Pharmacol. 11: 109P, 1980.Google Scholar
- 7.Black, A. K., Fineham, N., Greaves, M. W., and Hensby, C. N. Changes in levels of arachidonic acid and prostaglandins D2, E2, F2α, and 6-OXO-F1α in human skin within 48 hours after ultraviolet B irradiation. Br. J. Dermatol. 105: 353–354, 1980.Google Scholar
- 8.Camp, R., Greaves, M. W., Hensby, C. N., Plummer, N. A., and Warin, A. P. Irradiation of human skin by short wavelength ultraviolet irradiation (100-290 nm) (UVC): Increased concentrations of arachidonic acid and prostaglandins E2 and F2α. Br. J. Clin. Pharmacol. 6: 145–148, 1978.PubMedGoogle Scholar
- 14.Barr, R. M., Brain, S. D., Black, A. K., Camp, R. D., Greaves, M. W., Mallet, A. I., Wong, E., and Hensby, C. N. Lipoxygenase products of arachidonic acid in inflamed skin. J. Invest. Dermatol. 80(4): 345, 1983.Google Scholar