Characterization of L-lysine transport across equine and porcine jejunal and colonic brush border membrane.
Characterization of L-lysine transport across equine and porcine jejunal and colonic brush border membrane.
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L-赖氨酸跨马和猪空肠和结肠刷状缘膜转运的表征。
DOI：
10.2527/jas.2011-4210
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发表时间：
2012
影响因子：
3.3
通讯作者：
N. Trottier
中科院分区：
文献类型：
--
作者：
A. Woodward;M. Fan;R. Geor;L. J. McCutcheon;N. P. Taylor;N. Trottier
在非反刍草食动物中，微生物来源的 AA 有助于全身 AA 稳态，从而降低预期的 AA 需求。然而，AA 摄取后的能力目前尚不清楚。因此，为了检验赖氨酸跨大结肠粘膜顶膜转运的假设，其能力与小马和猪的小肠粘膜相似，我们使用刷状缘膜囊泡（BBMV）在体外检查了赖氨酸的转运。从生长猪 (n = 3) 和小马 (n = 4) 的远端空肠 (DJ) 和近端大结肠 (PLC) 收集粘膜，在液氮中快速冷冻，并储存在 -80°C 下。通过 Mg(2+) 沉淀制备空肠和结肠 BBMV，并用于通过 Na(+) 梯度孵育缓冲液中的快速过滤技术确定 L-Lys 转运至顶上皮的初始速率和动力学 [最大转运速率 (V(max)) 和米氏常数 (K(M))]。在每个 L-Lys 浓度下，猪或小马的 PLC 和 DJ 之间，或者小马和猪之间，总 L-Lys 摄取的初始速率没有差异。在猪中，与 DJ 相比，PLC 中的 l-Lys 转运 V(max) 没有差异（分别为 121 ± 26 和 180 ± 26 pmol•mg 蛋白质(-1)•s(-1)；P = 0.14）和 PLC 中的 l-Lys K(M) 往往更大（分别为 0.23 ± 0.22 和 0.89 ± 0.22 mM；P = 0.09）。在小马中，与 DJ 相比，PLC 中的 l-Lys 转运 V(max) 更大（分别为 62 ± 25 和 149 ± 25 pmol•mg 蛋白质(-1)•s(-1)；P = 0.04），PLC 中的 l-Lys K(M) 更大（分别为 0.08 ± 0.22 和 1.05 ± 0.22 mM；P = 0.02）。 L-赖氨酸扩散在各段之间没有差异；然而，小马的总肠道扩散量高于猪（P = 0.03）（分别为 115 ± 10 和 73 ± 10 pmol·mg 蛋白质(-1)·s(-1)）。这些结果表明，大结肠能够以比空肠更大的容量和更低的亲和力跨顶上皮膜运输l-Lys，表明大结肠可能在后肠发酵罐中的l-Lys吸收和稳态中发挥重要作用。
In nonruminant herbivores, microbially derived AA could contribute to whole-body AA homeostasis and thus decrease predicted AA requirements. However, postileal capacity of AA uptake is currently unknown. Therefore, to test the hypothesis that Lys is transported across the large colon mucosal apical membrane with capacity similar to that of the small intestinal mucosa in the pony and pig, we examined Lys transport in vitro using brush border membrane vesicles (BBMV). Mucosa was collected from the distal jejunum (DJ) and proximal large colon (PLC) of growing pigs (n = 3) and ponies (n = 4), flash frozen in liquid nitrogen, and stored at -80°C. Jejunal and colonic BBMV were manufactured by Mg(2+) precipitation and used to determine initial rates and kinetics [the maximal transport rate (V(max)) and the Michaelis constant (K(M))] of l-Lys transport into apical epithelia by rapid filtration technique in Na(+)-gradient incubation buffer. Initial rates of total l-Lys uptake did not differ between the PLC and DJ in either the pig or the pony, or between the pony and the pig, at each l-Lys concentration. In the pig, compared with the DJ, l-Lys transport V(max) in the PLC did not differ (121 ± 26 and 180 ± 26 pmol•mg of protein(-1)•s(-1), respectively; P = 0.14) and l-Lys K(M) in the PLC tended to be greater (0.23 ± 0.22 and 0.89 ± 0.22 mM, respectively; P = 0.09). In the pony, compared with the DJ, l-Lys transport V(max) in the PLC was greater (62 ± 25 and 149 ± 25 pmol•mg of protein(-1)•s(-1), respectively; P = 0.04) and l-Lys K(M) in the PLC was greater (0.08 ± 0.22 and 1.05 ± 0.22 mM, respectively; P = 0.02). l-Lysine diffusion was not different between segments; however, total intestinal diffusion was greater (P = 0.03) in the pony than in the pig (115 ± 10 and 73 ± 10 pmol·mg of protein(-1)•s(-1), respectively). These results demonstrate that the large colon is capable of l-Lys transport across the apical epithelial membrane with greater capacity and less affinity than the jejunum, indicating that the large colon may play a significant role in l-Lys absorption and homeostasis in hindgut fermenters.
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马盲肠粘膜体外转运 L-丙氨酸。
影响因子：
1
作者：
Freeman,DE;Kleinzeller,A;Donawick,WJ;Topkis,VA
通讯作者：
Topkis,VA
DOI：
10.1002/jez.1402520519
发表时间：
1989
期刊：
The Journal of experimental zoology. Supplement : published under auspices of the American Society of Zoologists and the Division of Comparative Physiology and Biochemistry
影响因子：
--
作者：
Obst,BS;Diamond,JM
通讯作者：
Diamond,JM
结肠刷状缘膜中的钠-质子交换。
DOI：
10.1152/ajpgi.1986.251.3.g382
发表时间：
1986
期刊：
The American journal of physiology
影响因子：
--
作者：
Binder,HJ;Stange,G;Murer,H;Stieger,B;Hauri,HP
通讯作者：
Hauri,HP
大鼠结肠刷状缘膜囊泡中的 Na-H 交换。
DOI：
10.1152/ajpgi.1986.250.6.g781
发表时间：
1986
期刊：
The American journal of physiology
影响因子：
--
作者：
Foster,ES;Dudeja,PK;Brasitus,TA
通讯作者：
Brasitus,TA