The Secretion of Parathormone Fragments 34–84 and 37–84 by Dispersed Porcine Parathyroid Cells

摘要: Dispersed porcine parathyroid cells were incubated with radioactive amino acid at 0.5 and 3.0 nw calcium, after which proteins of the medium analyzed. In addition to parathormone secretory protein-I, a carboxylterminal immunoactive fragment peak was detected that could be separated from intact hormone by differential precipitation 8–25% trichloroacetic acid. The components this analyzed for molecular size, peptides resulting tryptic digestion, sequences Edman degradation. results showed two derived present: 37–84 34–84, in ratio about 2:1. These fragments secreted rather than produced hormone, since under incubation conditions used, there little loss exogenous medium. However, omission serum (or, more specifically, α2-macroglobulin) led su...