Amine precursor uptake and decarboxylation: significance for processing of the rat gastrin precursor

The Journal of Physiology
S VoroninaA Varro

Abstract

1. Conversion of prohormone precursors to smaller active products occurs in secretory granules, which also have the capacity to concentrate biogenic amines. We have examined how processing of the gastrin precursor, progastrin, in rat antral mucosa is influenced by modulation of the biogenic amine content of secretory granules. 2. Newly synthesized progastrin-derived peptides in rat antral mucosa were labelled in vitro with 35SO4(2-) using a pulse-chase protocol and detected after immunoprecipitation by HPLC with on-line liquid scintillation counting. Secretory granule morphology was examined by electron microscopy. The effects of experimentally manipulating secretory granule pH and amine content were examined. 3. The dopamine precursor L-beta-3,4-dihydroxyphenylalanine (L-DOPA) inhibited cleavage of 35S-labelled thirty-four amino acid amidated gastrin, i.e. [35S]G34, and of [35S]G34 with COOH-terminal glycine, i.e. [35S]G34-Gly, at a pair of lysine residues, but did not influence cleavage of progastrin at pairs of arginine residues. The effect of L-DOPA was reversed by reserpine, which inhibits the amine-proton exchangers VMAT1 and VMAT2, and by carbidopa, which inhibits aromatic L-amino acid decarboxylase. 4. Treatments that r...Continue Reading

References

May 1, 1976·The Journal of Clinical Investigation·J H WalshV Maxwell
Nov 15, 1992·Proceedings of the National Academy of Sciences of the United States of America·J D EricksonB J Hoffman
Jan 1, 1990·The Journal of Clinical Investigation·J DelValle, T Yamada
Jan 1, 1986·Annual Review of Biochemistry·I MellmanA Helenius
Mar 1, 1988·The Journal of Cell Biology·R G Anderson, L Orci
Jan 1, 1988·Annual Review of Physiology·W B Huttner
May 1, 1969·The Journal of Histochemistry and Cytochemistry : Official Journal of the Histochemistry Society·A G Pearse
Jan 1, 1980·Histochemistry·M EkelundF Sundler
Jan 1, 1982·Annual Review of Physiology·K Docherty, D F Steiner
Sep 1, 1995·The Journal of Clinical Investigation·C J DickinsonT Yamada
Apr 1, 1995·The Journal of Clinical Investigation·A VarroG J Dockray
Sep 15, 1994·Annals of the New York Academy of Sciences·K Langley

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Citations

Jan 14, 2000·European Journal of Pharmacology·E LindströmR Håkanson
Feb 22, 2001·Annual Review of Physiology·G J DockrayT Wang
Jun 25, 1999·The Journal of Physiology·G J Dockray

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