Ontogeny of procholecystokinin processing in rat hypothalamus.
The concentration of procholecystokinin (pro-CCK) in the fetal hypothalamus was 126 +/- 41 pmol/g (mean +/- SEM; n = 20), 22 +/- 9 pmol/g at day 7 postpartum and 3 +/- 2 pmol/g in the adult. In contrast, the concentration of bioactive carboxyamidated CCK rose from 6 +/- 2 pmol/g in the fetal hypothalamus to 52 +/- 10 pmol/g in the adult. The concentration of glycine-extended processing intermediates first decreased from 21 +/- 5 pmol/g in the fetus to 5 +/- 1 pmol/g at day 21 postpartum. Subsequently, the concentration rose to 21 +/- 4 pmol/g in the adult. The results show that the CCK gene is well expressed in the fetal hypothalamus. However, only a small fraction of pro-CCK reaches maturation before weaning. We conclude that expression of the CCK gene in the hypothalamus as bioactive peptide to a large degree is regulated at the posttranslational level.
Mogensen
N W
NW
Department of Clinical Chemistry, Rigshospitalet, University of Copenhagen, Denmark.
Hilsted
L
L
Bardram
L
L
Rehfeld
J F
JF
D000595:Amino Acid Sequence; D000818:Animals; D002766:Cholecystokinin / Q000096:biosynthesis*; D002850:Chromatography, Gel; D005260:Female; D007031:Hypothalamus / Q000254:growth & development* / Q000378:metabolism; D007202:Indicators and Reagents; D008969:Molecular Sequence Data; D011247:Pregnancy; D011498:Protein Precursors / Q000096:biosynthesis*; D011863:Radioimmunoassay; D051381:Rats; D012979:Sodium Radioisotopes
D007202:Indicators and Reagents; D011498:Protein Precursors; D012979:Sodium Radioisotopes; C060249:procholecystokinin; D002766:Cholecystokinin