Photoreactivation of ultraviolet radiation-induced skin and eye tumors of Monodelphis domestica.

摘要: Chronic exposure of the opossum Monodelphis domestica to UV radiation (UVR) leads formation cutaneous and corneal tumors. Groups shaved opossums were exposed 3 times/week to: ( a ) UVR alone; b followed immediately by 1 h photoreactivating light (PRL) (320–700 nm); c PRL UVR; d alone. Exposures terminated after 70 weeks treatment. Analysis data plotted as probability tumor versus from first shows that post-UVR significantly P < 0.005) delayed time appearance tumors 50% at 73 for those animals alone 128 UVR. Pre-UVR 6 when compared group, but difference between two groups was not statistically significant. The yield (number tumors/surviving animal) 110 following initiation treatments also less in after, before, Based on specificity PR repair pathway act only pyrimidine dimers, these results suggest dimers are involved induction obtained with more difficult interpret. While tumors, magnitude effect same regardless whether given before or each exposure.