Institut des Sciences de la Vie, Université catholique de Louvain, Croix du Sud 2/L7.05.08, B-1348 Louvain-la-Neuve, Belgium.
Comp Biochem Physiol A Mol Integr Physiol. 2012 Aug;162(4):323-30. doi: 10.1016/j.cbpa.2012.04.001. Epub 2012 Apr 6.
We investigated the changes of vitamins A and E as well as PCBs and DDTs during lactation in northern elephant seal (Mirounga angustirostris) mother-pup pairs. On average, milk vitamin A concentrations were 6 times higher during late lactation than during early lactation, a pattern that differs dramatically from terrestrial mammals. Vitamin A concentrations also significantly increased in the inner blubber throughout lactation, whereas they remained constant in the outer blubber. Similar dynamics were observed for PCBs and DDTs in maternal blubber and milk. Blubber appears to be an important storage site for vitamin A and organochlorines in seals and a direct transfer of those molecules to the mammary gland may occur. The dynamics of vitamin A, PCBs and DDTs differed from those of vitamin E. There was a significant drop in milk vitamin E concentrations between early and late lactation, which is the usual pattern observed in terrestrial mammals. The dynamics of vitamin E in the blubber layers also differed from those of vitamin A, suggesting different mechanisms of mobilization and transfer into the milk.
我们研究了在北象海豹（Mirounga angustirostris）母幼对哺乳期内维生素 A 和 E 以及多氯联苯和滴滴涕的变化。平均而言，与陆地哺乳动物有显著差异，在哺乳期后期，牛奶中的维生素 A 浓度是早期的 6 倍。维生素 A 浓度在整个哺乳期内在内层鲸脂中显著增加，而在外层鲸脂中保持不变。母体鲸脂和牛奶中的多氯联苯和滴滴涕也表现出类似的动态。鲸脂似乎是海豹体内维生素 A 和有机氯的重要储存场所，这些分子可能直接转移到乳腺。维生素 A、多氯联苯和滴滴涕的动态与维生素 E 不同。在早期和晚期哺乳期之间，牛奶中维生素 E 浓度显著下降，这是陆地哺乳动物中常见的模式。鲸脂层中维生素 E 的动态也与维生素 A 不同，这表明其动员和转移到牛奶中的机制不同。
