Abizaid A, Walker C D, Woodside B
Center for Studies in Neurobiology and Department of Psychology, Concordia University, Montreal, Que., Canada.
Brain Res. 1997 Jul 4;761(2):306-12. doi: 10.1016/s0006-8993(97)00351-x.
Previous studies have demonstrated that food restriction during lactation extends the length of lactational infertility in rats. In order to determine whether Neuropeptide Y (NPY) plays a role in the increased length of lactational infertility seen in food-restricted rats, NPY immunoreactivity in the arcuate nucleus of lactating rats that were ad lib fed or food restricted from Day 8 to 14 postpartum was compared. Food-restricted rats showed higher numbers of NPY-stained cells at the end of the food-restriction period (Day 15 postpartum) than did ad lib-fed rats at the same stage of lactation. This difference persisted until Day 25 postpartum although all animals were fed ad libitum from Day 15 onwards. Switching litters between ad lib-fed and food-restricted females from Day 15 until Day 20 postpartum did not eliminate the difference in NPY immunoreactivity between the two diet conditions. Given that food restriction during lactation leads to a prolonged suppression of LH release that also persists after refeeding and is not affected by the nutritional status of the litter, these data are consistent with a role for NPY in the prolonged suppression of reproductive function seen in food restricted lactating rats.
先前的研究表明，哺乳期限制食物摄入会延长大鼠哺乳期不孕的时长。为了确定神经肽Y（NPY）是否在食物受限大鼠哺乳期不孕时长增加中发挥作用，研究人员比较了产后第8天至14天自由采食或食物受限的哺乳期大鼠弓状核中的NPY免疫反应性。在食物限制期结束时（产后第15天），食物受限大鼠的NPY染色细胞数量高于处于相同哺乳期阶段的自由采食大鼠。尽管从第15天起所有动物均自由采食，但这种差异一直持续到产后第25天。在产后第15天至第20天之间，将自由采食和食物受限雌性大鼠的幼崽进行交换，并未消除两种饮食条件下NPY免疫反应性的差异。鉴于哺乳期食物限制会导致促黄体生成素（LH）释放的长期抑制，这种抑制在重新喂食后仍然存在，并且不受幼崽营养状况的影响，这些数据表明NPY在食物受限哺乳期大鼠生殖功能的长期抑制中发挥作用。
