Measurement of Late Tissue Damage in Rhesus Monkeys Exposed to Protons

摘要

This contract covered studies of the following endpoints in proton- irradiated rhesus monkeys and in age-matched controls: (1) Radiation-accelerated aging of skin fibroblasts in vitro; (2) Wound healing in vivo; (3) Late radiogenic cataracts in rhesus monkeys; (4) Comparative studies of proton- induced cataracts in Fischer-344 rats. (1 & 2) Some deficits in the abilities of monkey skin fibroblasts to perform normal functions in vitro and in vivo were noted following radiation doses slightly higher than those to be expected in space, but it was concluded that following 'expected' doses of space radiation, late harmful sequelae will be negligible or undetectable in human skin. (3 & 4) Late cataracts may occur in the ocular lenses of some astronauts exposed to non- lethal space radiations, but the kinetics of radiation cataractogenesis in the rhesus monkey indicate that radiogenic cataracts should not develop until long after the space mission(s) is (are) over. Laboratory rats are not good models for late cataract studies because of their short life spans and the high levels of cataracts that appear naturally in them early in their life span.