Hastings I M, Yang J Y, Hill W G
Institute of Cell, Animal and Population Biology, University of Edinburgh, Scotland.
Genet Res. 1991 Dec;58(3):253-9. doi: 10.1017/s0016672300030007.
Lines of mice have been selected for 32 generations for either high or low fat content, resulting in a threefold divergence in the selection criterion (estimated fat content of males at 14 weeks of age). Male mice from both lines were dissected at a series of ages between 4 and 26 weeks and the following traits measured or estimated: body weight, fat content, lean weight, and the weights of several fatpads and internal organs. The lines appeared to have a similar underlying lean weight upon which the Fat line accumulated fat at a faster rate. This accumulation continued unabated in the Fat lines for at least 26 weeks but had effectively ceased by 8 weeks of age in the Lean. The liver and kidneys were slightly larger in the Fat line but there were no differences in the weights of heart, lung or spleen. This detailed phenotypic description of the lines complemented previous reports describing correlated changes in their physiology. The threefold divergence in estimated fat content was less than that in one of its component traits, growth of gonadal fatpad, but was greater than the divergence in other physiological indicators, i.e. the activity of lipogenic enzymes in vitro and direct measurement of lipogenic flux. Testis size in the Fat line was consistently lower than in the Lean although the Fat line was slightly more fecund, apparently due to a higher prenatal survival rate.
已经对小鼠品系进行了32代的高脂或低脂含量选育，导致选择标准（14周龄雄性小鼠的估计脂肪含量）出现了三倍的差异。在4至26周的一系列年龄阶段，对两个品系的雄性小鼠进行解剖，并测量或估计以下特征：体重、脂肪含量、瘦体重以及几个脂肪垫和内脏器官的重量。两个品系似乎具有相似的潜在瘦体重，在此基础上，高脂品系以更快的速度积累脂肪。在高脂品系中，这种积累至少持续了26周且未减弱，但在低脂品系中到8周龄时已有效停止。高脂品系的肝脏和肾脏稍大，但心脏、肺或脾脏的重量没有差异。对这些品系的详细表型描述补充了先前描述其生理学相关变化的报告。估计脂肪含量的三倍差异小于其组成性状之一——性腺脂肪垫生长的差异，但大于其他生理指标的差异，即体外脂肪生成酶的活性和脂肪生成通量的直接测量。高脂品系的睾丸大小始终低于低脂品系，尽管高脂品系的繁殖力略高，这显然是由于产前存活率较高。
