Cochet N, Georges B, Meister R, Florant G L, Barré H
Laboratoire de Physiologie des Régulations Energétiques, Cellulaires et Moléculaires (UMR 5578 CNRS-UCB), Université LYON I, Villeurbanne, France.
Lipids. 1999 Mar;34(3):275-81. doi: 10.1007/s11745-999-0364-x.
Alpine marmots (Marmota marmota) were maintained on a laboratory diet, and the fatty acid composition of gonadal and subcutaneous white adipose tissues (WAT) was studied during a yearly cycle. Fatty acids (FA) released from isolated adipocytes were also identified after stimulation of in vitro lipolysis. Analysis of the FA composition of WAT depots showed that marmot WAT mainly contained monounsaturated FA (65%, mostly oleic acid, 18:1n-9) although laboratory food contained 45% of linoleic acid (18:2n-6) and only 21% of 18:1n-9. During stimulated lipolysis, saturated FA were preferentially released from isolated adipocytes whereas unsaturated FAs were retained. Despite this selective release of FA from isolated WAT cells in vitro, and despite the FA composition of the food, marmots maintained a constant FA composition in both WAT depots throughout the year. Six months of hibernation and fasting as well as an intense feeding period did not affect this composition. The potential adaptive benefit of such regulation of WAT composition, based on a high level of monounsaturated FA, might be to maintain fat with appropriate physical properties allowing animals to accommodate to and survive the wide range of body temperatures experienced during hibernation.
将高山旱獭（Marmota marmota）饲养在实验室环境中，以实验室饲料喂养，并在一年的周期内研究其性腺和皮下白色脂肪组织（WAT）的脂肪酸组成。在体外刺激脂肪分解后，还对分离出的脂肪细胞释放的脂肪酸（FA）进行了鉴定。对WAT库中FA组成的分析表明，旱獭的WAT主要含有单不饱和脂肪酸（65%，主要是油酸，18:1n-9），尽管实验室饲料中含有45%的亚油酸（18:2n-6），而18:1n-9仅占21%。在刺激脂肪分解过程中，饱和脂肪酸优先从分离出的脂肪细胞中释放，而不饱和脂肪酸则被保留。尽管在体外从分离的WAT细胞中有这种脂肪酸的选择性释放，并且尽管饲料中的脂肪酸组成如此，但旱獭全年在两个WAT库中的脂肪酸组成保持恒定。六个月的冬眠和禁食以及一个强烈的进食期都没有影响这种组成。基于高水平的单不饱和脂肪酸，这种对WAT组成的调节潜在的适应性益处可能是维持具有适当物理性质的脂肪，使动物能够适应并在冬眠期间经历的广泛体温范围内生存。
