Urinary total hydroxyproline, peptide-bound hydroxyproline,
hydroxylysine glycosides, and calcium were measured in three healthy
individuals subjected to weightlessness for eighty-four days and in three
young quadriplegic patients. The former group had significant calciuria but
no evidence of collagen degradation. The latter group, however, had
conspicuous calciuria and also excreted large amounts of collagen breakdown
products. This documented degradation of matrix may be related to the
continuous calciuria, osteoporosis, and cutaneous dystrophic changes
occurring in quadriplegics.