A glucose sensor role for glucokinase in anterior pituitary cells.
Enzymatic activity of glucokinase was demonstrated, quantitated, and characterized kinetically in rat and mouse pituitary extracts using a highly specific and sensitive spectrometric assay. A previously proposed hypothesis that the glucokinase gene might be expressed in the pituitary corticotrophic cells was therefore reexamined using mRNA in situ hybridization and immunohistochemical techniques. No evidence was found that corticotrophs are glucokinase positive, and the identity of glucokinase-expressing cells remains to be determined. The findings do, however, suggest a novel hypothesis that a critical subgroup of anterior pituitary cells might function as glucose sensor cells and that direct fuel regulation of such cells may modify the classical indirect neuroendocrine pathways that are known to control hormone secretion from anterior pituitary cells.
Zelent
Dorothy
D
University of Pennsylvania School of Medicine, BiochemistryBiophysics, 501 Stemmler Hall, 36th & Hamilton Walk, Philadelphia, PA 19104, USA.
Golson
Maria L
ML
Koeberlein
Brigitte
B
Quintens
Roel
R
van Lommel
Leentje
L
Buettger
Carol
C
Weik-Collins
Heather
H
Taub
Rebecca
R
Grimsby
Joseph
J
Schuit
Frans
F
Kaestner
Klaus H
KH
Matschinsky
Franz M
FM
D000324:Adrenocorticotropic Hormone / Q000235:genetics; D000818:Animals; D015374:Biosensing Techniques; D005260:Female; D015971:Gene Expression Regulation, Enzymologic; D005941:Glucokinase / Q000235:genetics*; D013006:Growth Hormone / Q000235:genetics; D017403:In Situ Hybridization; D007700:Kinetics; D008099:Liver / Q000201:enzymology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D020411:Oligonucleotide Array Sequence Analysis; D010903:Pituitary Gland, Anterior / Q000201:enzymology*; D011333:Pro-Opiomelanocortin / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats
D012333:RNA, Messenger; D011333:Pro-Opiomelanocortin; D000324:Adrenocorticotropic Hormone; D013006:Growth Hormone; D005941:Glucokinase