Serum procollagen type III peptide levels in normal rhesus monkeys

Serum levels of the amino-terminal peptide of Type III procollagen (P-III-P) were assayed by radioimmunoassay in 48 Rhesus monkeys from 0.7 to 26.4 years of age. Serum P-III-P levels in ten juvenile monkeys (0.7-4.7 yrs.) were significantly higher (84.5 +/- 66.2 ng/ml, p = 0.05) and ranged from 29.6 to 238.0 ng/ml as compared with 38 monkeys over 5 years of age (21.7 - 9.4 ng/ml), which ranged from 8.5 to 55.5 ng/ml. No significant differences in serum P-III-P levels were observed between any age groups over 5 years of age (5-10, 10-15, 15-20, and > 20) or between male and female monkeys within any age category.