EFFECT OF ENVIRONMENTAL TEMPERATURE AND UNDERNUTRITION ON COLLAGEN AGING

Contractility of tail collagen in NaClO4 and solubility of skin collagen in 0·1 N acetic acid were measured in mice or rats under various regimés. In mice kept 1 yr at 2°C, aging of tail collagen was slowed down compared with warm-reared controls, while extractability of skin collagen was unchanged. In rats, implantation of tails under the skin, so that the tails were maintained at body temperature, was found to accelerate collagen aging. Accordingly changes in tail and in skin collagen were measured in underfed and in control groups of rats with implanted and unimplanted tails: the slowing of tail-collagen aging by underfeeding was absent in implanted tails. We suggest that underfeeding slows down tail collagen aging, judged by contractility, by a decrease of local temperature in the tail rather than by reduction of crosslinking with reduced metabolism. © 1969.