Larsen T S, Nilsson N O, Blix A S
Acta Physiol Scand. 1985 Jan;123(1):97-104. doi: 10.1111/j.1748-1716.1985.tb07566.x.
Arctic reindeer exhibit marked seasonal changes in fat deposition and mobilization. At intervals throughout the year, therefore, we have measured feed intake of both Svalbard (SR) and Norwegian reindeer (NR) together with the seasonal changes in size, lipogenic and lipolytic capacity of isolated adipocytes from both sub-species. Feed intake of both NR and SR was maximal in August, but declined thereafter, reaching minimum values in January (NR) and March (SR), 55 and 69% below the August value, respectively. NR and SR adipocyte volume changed in parallel and were reduced to the same extent (69%) from their maximum in August to their minimum in May. Adipocyte lipogenic capacity, measured as acetate incorporation into cellular lipid at saturated acetate concentrations, was lowest in January (NR adipocytes) and March (SR adipocytes), 92 and 90%, respectively, below the maximum values, which were obtained in August. Lipolytic capacity, measured as maximum adrenaline-stimulated glycerol release, was high in SR adipocytes from March through to October and in NR adipocytes from July through to January. Minimum lipolytic capacity, on the other hand, was found in January (SR adipocytes) and March (NR adipocytes). The present findings may be explained by alterations in lipogenic enzyme activity and in the lipolytic activation system.
北极驯鹿的脂肪沉积和动员呈现出明显的季节性变化。因此，在一年中的不同时间，我们测量了斯瓦尔巴德驯鹿（SR）和挪威驯鹿（NR）的采食量，以及这两个亚种分离脂肪细胞大小、生脂能力和脂解能力的季节性变化。NR和SR的采食量在8月时最大，但此后下降，在1月（NR）和3月（SR）达到最小值，分别比8月的值低55%和69%。NR和SR脂肪细胞体积平行变化，从8月的最大值到5月的最小值均减少了相同程度（69%）。以饱和醋酸盐浓度下醋酸盐掺入细胞脂质来衡量的脂肪细胞生脂能力，在1月（NR脂肪细胞）和3月（SR脂肪细胞）最低，分别比8月获得的最大值低92%和90%。以最大肾上腺素刺激甘油释放来衡量的脂解能力，在3月至10月的SR脂肪细胞以及7月至1月的NR脂肪细胞中较高。另一方面，最低脂解能力出现在1月（SR脂肪细胞）和3月（NR脂肪细胞）。目前的研究结果可能由生脂酶活性和脂解激活系统的改变来解释。
