Buchberger P, Schmidt I
W.G. Kerckhoff Institut, Max Planck Institut für Physiologische, Bad Nauheim, Germany.
Am J Physiol. 1996 Aug;271(2 Pt 2):R472-6. doi: 10.1152/ajpregu.1996.271.2.R472.
We wanted to find out whether fatty (fa/fa) sucklings show abnormal intake when given access to an abundant milk reservoir. To do this, we gravimetrically determined the milk ingested by small groups (4-5 pups) of 5- to 15-day-old lean (+/fa) and fatty littermates allowed to suckle for 30 min after their mother had not been nursing for periods of between 1 and 7 h. The pups were grouped randomly and their phenotypes retrospectively identified. Within both genotypes, the intakes of simultaneously tested pups were significantly higher in pups deprived for longer periods. Deprived and undeprived fa/fa pups ingested, however, slightly but significantly less milk than +/fa littermates did in the same nursing bout. In the first 2 wk of life, when fa/fa pups deposit nearly twice as much body fat as their +/fa littermates do, fa/fa pups will thus suckle less rather than more milk. This extends previous findings showing that the onset of fa/fa obesity is independent of larger intakes and thus questions that fa impairs a receptor primarily controlling food intake.
我们想弄清楚，当有充足的乳汁供应时，肥胖型（fa/fa）乳鼠的摄入量是否会出现异常。为此，我们采用重量法测定了5至15日龄的瘦型（+/fa）和肥胖型同窝乳鼠（每组4 - 5只幼崽）的乳汁摄入量。这些幼崽在其母亲停止哺乳1至7小时后，被允许哺乳30分钟。幼崽被随机分组，并对它们的表型进行回顾性鉴定。在两种基因型中，被剥夺哺乳时间更长的幼崽，其同时测试的幼崽的摄入量显著更高。然而，在同一轮哺乳中，被剥夺和未被剥夺哺乳的fa/fa幼崽摄入的乳汁量略低于但显著低于+/fa同窝幼崽。在出生后的前2周，当fa/fa幼崽积累的体脂几乎是其+/fa同窝幼崽的两倍时，fa/fa幼崽会因此吸食更少而非更多的乳汁。这扩展了先前的研究结果，即fa/fa肥胖症的发病与更多的摄入量无关，因此对fa基因损害主要控制食物摄入量的受体这一观点提出了质疑。
