Cell membrane transport enzymes in cultured dermal fibroblasts from progeroid donors: a comparison to other human fibroblasts.

Cell membranes from progeroid fibroblasts had an elevated Na+, K+ ATPase. Ca++ ATPase and gamma-glutamyl transpeptidase were markedly decreased in progeroid fibroblast membranes. 5'-nucleotide phosphatase was unchanged, compared to age- and sex-matched normal fibroblast membranes. Fetal lung fibroblasts and dermal fibroblast from myotonic dystrophy victims had enzyme activities similar to those of the normal dermal fibroblasts.