Figure 5.

Proliferation and type I procollagen synthesis by fibroblasts from severely photodamaged forearm skin and sun-protected hip skin are similar. Cell number values (top) are averages ± standard errors, based on 22 and 29 isolates from forearm and hip, respectively. Collagen synthesis values (bottom) represent average amounts of type I procollagen secreted into 1 ml of culture medium (normalized to 8 × 10 4 cells) during a 1-hour incubation period ± standard errors, based on 12 and 23 isolates from forearm and hip, respectively. Statistical significance was determined by Student’s t-test. Values from the two groups were not different from one another at the P < 0.05 level.