Murillo-Fuentes M L, Artillo R, Ojeda M L, Delgado M J, Murillo M L, Carreras O
Department of Physiology and Zoology, Faculty of Pharmacy, University of Seville, Seville, Spain.
Alcohol Alcohol. 2007 Jan-Feb;42(1):3-10. doi: 10.1093/alcalc/agl084. Epub 2006 Oct 26.
The effect of ethanol consumption, either during the pregnancy or lactation period, on the altered metabolism of zinc is not well-defined; consequently, this study was performed to analyze the effect of chronic ethanol exposure on milk consumption, serum, milk, duodenal absorption, fecal and urinary excretion of zinc in dams and offspring during either gestation or lactation in the rat. A complementary study was performed regarding pregnancy outcome. We evaluated testosterone values, the offspring born/litter and several indices such as fertility, viable gestations and the survival index.
To study the effect of chronic alcoholism during gestation or lactation separately, at birth control newborns were cross-fostered to ethanol dams (ED), and the offspring issued from the ethanol treated mothers were cross-fostered to control dams (CD). Thus, three experimental groups of offspring were formed: (i) control offspring receiving no treatment (CO); (ii) offspring exposed to ethanol only during gestation (GO); and (iii) offspring exposed to ethanol only during lactation (LO). All the results were compared with offspring pair-fed groups (PFO) born of the pair-fed dams (PFD).
Duodenal absorption of zinc increased significantly in LO offspring when the substrate concentrations in the perfusion medium were 25, 75, and 150 microM. A higher faecal excretion in GO pups compared with those with LO exposure and control groups (CO and PFO). The urine excretion of zinc was higher for LO offspring with respect to the other three experimental groups (CO, GO, and PFO).
Maternal adaptation resulted in zinc retention, adequate to meet the demands of pup's growth in the face of a lower diet intake. The zinc status in pups is regulated by a higher absorption of zinc and intestinal conservation of endogenous fecal zinc after postnatal ethanol consumption. The increase in urinary zinc excretion could be responsible for decreased serum zinc. However, we found an increase in serum zinc probably due to an increase in the zinc absorption values.
孕期或哺乳期摄入乙醇对锌代谢改变的影响尚不明确；因此，本研究旨在分析慢性乙醇暴露对大鼠孕期或哺乳期母鼠及其后代的牛奶摄入量、血清、乳汁、十二指肠吸收、粪便和尿液中锌排泄的影响。还进行了一项关于妊娠结局的补充研究。我们评估了睾酮值、每窝出生的后代数量以及生育力、活胎妊娠和存活指数等几个指标。
为分别研究孕期或哺乳期慢性酒精中毒的影响，出生时将对照新生幼崽交叉寄养给乙醇处理的母鼠（乙醇母鼠），将乙醇处理的母鼠所生后代交叉寄养给对照母鼠（对照母鼠）。这样就形成了三个实验组的后代：（i）未接受任何处理的对照后代（对照后代）；（ii）仅在孕期暴露于乙醇的后代（孕期暴露后代）；（iii）仅在哺乳期暴露于乙醇的后代（哺乳期暴露后代）。所有结果均与成对喂养母鼠（成对喂养母鼠）所生的成对喂养后代组（成对喂养后代）进行比较。
当灌注培养基中的底物浓度为25、75和150微摩尔时，哺乳期暴露后代的十二指肠锌吸收显著增加。与哺乳期暴露后代和对照组（对照后代和成对对喂养后代）相比，孕期暴露幼崽的粪便排泄量更高。哺乳期暴露后代的锌尿排泄量相对于其他三个实验组（对照后代、孕期暴露后代和成对对喂养后代）更高。
母体适应性变化导致锌潴留，足以在饮食摄入量较低的情况下满足幼崽生长的需求。幼崽的锌状态通过产后摄入乙醇后锌吸收增加和肠道对内源性粪便锌的保留来调节。尿锌排泄增加可能是血清锌降低的原因。然而，我们发现血清锌增加可能是由于锌吸收值增加。
