Characterization and functional role of leptin receptor in bovine adrenal medullary cells.
We report here the characterization and functional roles of the leptin receptor (ObR) in bovine adrenal medullary cells. The plasma membranes isolated from bovine adrenal medulla showed a single class of specific binding sites of (125)I-leptin with an apparent K(d) of 6.6 nM and B(max) of 62 fmol/mg protein. ObRa but not ObRb mRNA was detected in bovine adrenal medulla by reverse transcriptase-polymerase chain reaction. Incubation of cultured adrenal medullary cells with leptin (3-30 nM) for 20 min resulted in a significant increase in [(14)C]catecholamine synthesis from [(14)C]tyrosine without any change in catecholamine secretion. These findings suggest that leptin stimulates catecholamine synthesis through its receptors in bovine adrenal medullary cells.
Yanagihara
N
N
Department of Pharmacology, University of Occupational and Environmental Health, School of Medicine, Kitakyushu, Japan. yanagin@med.uoeh-u.ac.jp
Utsunomiya
K
K
Cheah
T B
TB
Hirano
H
H
Kajiwara
K
K
Hara
K
K
Nakamura
E
E
Toyohira
Y
Y
Uezono
Y
Y
Ueno
S
S
Izumi
F
F
D000313:Adrenal Medulla / Q000166:cytology / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D002395:Catecholamines / Q000378:metabolism; D002417:Cattle; D002478:Cells, Cultured; D007457:Iodine Radioisotopes; D020738:Leptin / Q000378:metabolism*; D008969:Molecular Sequence Data; D011956:Receptors, Cell Surface; D054411:Receptors, Leptin; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid
D002352:Carrier Proteins; D002395:Catecholamines; D007457:Iodine Radioisotopes; D020738:Leptin; D011956:Receptors, Cell Surface; D054411:Receptors, Leptin