Devaskar S U, Ollesch C, Rajakumar R A, Rajakumar P A
Department of Pediatrics, University of Pittsburgh, Magee-Womens Research Institute, Pennsylvania 15213-3180, USA.
Biochem Biophys Res Commun. 1997 Sep 8;238(1):44-7. doi: 10.1006/bbrc.1997.7237.
We examined the developmental changes in murine white and brown adipose tissue leptin and circulating immunoreactive total leptin concentrations. The approximately 4.4 kb leptin mRNA levels were higher at 2 and 7d postnatal ages, but declined to adult levels by the 14d stage and remained so until 160d. Paralleling the mRNA concentrations, leptin peptide levels also were higher at 2d, 7d, and 14d, declining to adult values by the 21d weaning stage. No difference in mRNA levels was observed between brown-enriched and white adipose tissue. No sexual dimorphism was observed in the leptin mRNA or peptide levels between 14 and 160d; however, at 2 and 7d, while no sex related differences were observed in the peptide levels, adipose mRNA concentrations were mildly higher in males than in the females. We conclude that leptin mRNA and peptide levels are higher during consumption of a high fat milk diet. High levels of leptin with increasing food intake and body weight gain signify hypothalamic leptin receptor resistance during the immediate postnatal period.
我们研究了小鼠白色和棕色脂肪组织中瘦素以及循环中免疫反应性总瘦素浓度的发育变化。约4.4 kb的瘦素mRNA水平在出生后2天和7天时较高，但在14天阶段降至成年水平，并一直保持到160天。与mRNA浓度平行，瘦素肽水平在2天、7天和14天时也较高，在21天断奶阶段降至成年值。富含棕色脂肪组织和白色脂肪组织之间未观察到mRNA水平的差异。在14至160天之间，瘦素mRNA或肽水平未观察到性别差异；然而，在2天和7天时，虽然在肽水平上未观察到与性别相关的差异，但雄性脂肪mRNA浓度略高于雌性。我们得出结论，在食用高脂肪乳类饮食期间，瘦素mRNA和肽水平较高。随着食物摄入量和体重增加，高水平的瘦素表明出生后即刻下丘脑存在瘦素受体抵抗。
