Resistin expression and regulation in mouse pituitary.
Resistin, a new adipocytokine, is expressed in human, rat and mouse adipose tissue. Its putative role as a mediator of insulin resistance is controversial. We hypothesized that resistin, in common with leptin, has multiple roles in non-adipose tissues. Using reverse transcription polymerase chain reaction (RT-PCR) we show that the resistin gene (Retn) is expressed in mouse brain (hypothalamus and cortex) and pituitary gland. Immunohistochemistry revealed resistin protein in the arcuate nucleus and pituitary gland. Semi-quantitative RT-PCR analysis indicated that Retn mRNA is developmentally regulated in the pituitary. Expression was lowest at birth, increased abruptly between postnatal days 14 and 25 (four-fold; P<0.001), and declined thereafter. This peak in pituitary Retn mRNA was unaffected by early weaning but was abolished by neonatal treatment with monosodium glutamate, suggesting that the basal hypothalamus regulates pituitary Retn. Although the role(s) of endogenous resistin in mouse brain and pituitary remains to be determined, it may be distinct from its controversial involvement in insulin resistance. Our data suggest that local resistin expression could have functional implications during prepubertal maturation of the hypothalamic-pituitary system.
Department of Obstetrics and Gynaecology, Faculty of Medicine, Dalhousie University, 5980 University Avenue, Halifax, NS, Canada B3J 3G9.
Barbara A
BA
Morash
Diane
D
Willkinson
Ehud
E
Ur
Michael
M
Wilkinson
D000375:Aging / Q000502:physiology*; D000818:Animals; D001921:Brain / Q000254:growth & development / Q000378:metabolism; D005260:Female; D018507:Gene Expression Regulation, Developmental / Q000502:physiology*; D006729:Hormones, Ectopic / Q000235:genetics*; D036341:Intercellular Signaling Peptides and Proteins; D051379:Mice; D008810:Mice, Inbred C57BL; D020932:Nerve Growth Factor; D009928:Organ Specificity; D010902:Pituitary Gland / Q000254:growth & development / Q000378:metabolism*; D011506:Proteins; D052243:Resistin; D020133:Reverse Transcriptase Polymerase Chain Reaction
D006729:Hormones, Ectopic; D036341:Intercellular Signaling Peptides and Proteins; D011506:Proteins; C486574:RETNLB protein, human; D052243:Resistin; C499623:Retn protein, mouse; C413576:Retnla protein, mouse; C486575:Retnla protein, rat; D020932:Nerve Growth Factor