Synthesis of leptin in human placenta.
Gender-based differences in serum leptin levels have been reported in umbilical cord blood, and leptin has been detectedin human amniotic fluid. In order to understand if leptin may be directly synthesized by human placentae an analysis made up of several steps was performed. First at all RT-PCR analysis from placenta-derived RNA was used to detect human leptin mRNA. The leptin-like immunoradioactivity detected in placentae extracts was identical to human leptin according to the criteria of charge, immunorecognition, SDS-PAGE analysis and blotting, indicating that intact leptin was found and no variants in size, charge or immunoactivity were present in the placentae. Finally an immunohistochemical analysis showed the presence of leptin in the cytoplasm of syncytiotrophoblast cells but not in the core of villi.


CONCLUSIONS
leptin is synthesized as a single molecular variant identical to human recombinant leptin in human placentae at delivery.
Señarís
R
R
Department of Physiology, University of Santiago de Compostela, Spain.
Garcia-Caballero
T
T
Casabiell
X
X
Gallego
R
R
Castro
R
R
Considine
R V
RV
Dieguez
C
C
Casanueva
F F
FF
D001483:Base Sequence; D017931:DNA Primers / Q000032:analysis / Q000737:chemistry / Q000235:genetics; D018076:DNA, Complementary / Q000032:analysis / Q000737:chemistry / Q000235:genetics; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D006801:Humans; D015151:Immunoblotting; D007150:Immunohistochemistry; D020738:Leptin; D010920:Placenta / Q000737:chemistry / Q000166:cytology / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D014176:Protein Biosynthesis; D011506:Proteins / Q000032:analysis / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis / Q000737:chemistry / Q000235:genetics
D017931:DNA Primers; D018076:DNA, Complementary; D020738:Leptin; D011506:Proteins; D012333:RNA, Messenger