The Kinetics of Ornithine Decarboxylase Activity as a Function of Wounding in Guinea Pig Ear Epidermis

Abstract

Guinea pig ear stratum corneum was removed to increasing depths by 1, 3, 6 or 9 strippings with adhesive tape. Increasing ornithine decarboxylase (ODC) activity responses were observed in the epidermis 4.5 hr after wounding with 3, 6 or 9 tape strippings. The kinetics of this ODC response were investigated at intervals including, 2, 4.5, 12, 18, 24 and 72 hr after tape stripping. ODC activity was significantly elevated for 12 hr after 3 or 6 tape strippings and for at least 72 hr after 9 tape strippings. These effects were independent of hair plucking or depilation prior to wounding. This model is potentially useful for comparing the effects of chemical, mechanical and physical stimuli on ODC activity and subsequent polyamine synthesis.

WAVELENGTH DEPENDENCE FOR ORNITHINE DECARBOXYLASE INDUCTION IN VIVO†

“…All procedures were conducted at 4°C unless otherwise noted. Tissue was homogenized according to the standard method (Bolton et al, 1981) in a sodium phosphate buffer (pH 7.2) containing pyridoxal phosphate, dithiothreitol and EDTA. The homogenate was centrifuged at 27 OOO g for 45 min in an RC-5 centrifuge and the clear supernatant extracts used as the enzyme source.…”