Epidermal growth factor stimulates chloride transport in primary cultures of weanling and adult rabbit colonocytes.
Epidermal growth factor stimulates chloride transport in primary cultures of weanling and adult rabbit colonocytes.
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表皮生长因子刺激断奶兔和成年兔结肠细胞原代培养物中的氯离子转运。
DOI：
10.1097/mpg.0b013e31802fca72
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发表时间：
2007
影响因子：
2.9
通讯作者：
Rao,MrinaliniC
中科院分区：
文献类型：
--
作者：
Carlos,MariaA;Nwagwu,Chimnoya;Ao,Mei;Venkatasubramanian,Jayashree;Boonkaewwan,Chaiwat;Prasad,Roli;Chowdhury,ShamimAK;Vidyasagar,Dharmapuri;Rao,MrinaliniC
目的：我们已经证明，哺乳动物结肠中ca2 +依赖性的Cl -分泌调节表现出年龄依赖性。由于表皮生长因子（epidermal growth factor， EGF）在生长中具有明确的作用，并可增加细胞内钙[ca2 +] i，因此可以想象其对发育的影响可能延伸到调节肠道离子运输。在这项研究中，我们研究了EGF在发育中的家兔远端结肠中调节Cl−运输的作用。材料和方法：由于血清中含有生长因子，这可能会混淆我们的研究，因此我们首先建立了一个最佳环境，通过在含有0%，1%，5%和20%血清的培养基中培养成年兔远端结肠炎细胞24小时来检测EGF。采用荧光指示剂N-（乙氧羰基甲基）-6-甲氧基喹啉溴化剂（MQAE）和Fura-2AM分别测定氯离子输运量（毫摩尔/秒）和[ca2 +] i。结果：血清缺失对细胞数量、DNA含量或基础Cl -转运没有影响，但显著影响细胞活力。在含有0%、1%或20%血清的培养基中，甲萘酚、8BrcAMP、牛磺酸去氧胆酸盐和EGF对Cl−转运的刺激程度相似。EGF在16.3 nmol/L和20分钟时最大程度地刺激Cl -转运。乙酰胆碱增加了[ca2 +] i。EGF不改变乙酰胆碱刺激的Cl -转运或[ca2 +] i。EGF通过EGF受体和丝裂原活化蛋白激酶（MAPK）信号通路起作用，因为刺激Cl -转运被染料木素、AG1478和PD98059消除。在1%血清中培养的断奶仔猪和成体结肠细胞显示出相似的基础和egf刺激的Cl -转运。结论：EGF通过ca2 +不依赖、酪氨酸激酶和mapk依赖的途径刺激家兔结肠Cl−运输，其作用不依赖于年龄。
Objectives:We have shown that Ca 2+-dependent regulation of Cl− secretion in the mammalian colon exhibits age dependence. Because epidermal growth factor (EGF) has a well-established role in growth and can increase intracellular calcium [Ca 2+] i, it is conceivable that its developmental influence may extend to the regulation of intestinal ion transport. In this study, we examined the role of EGF in the regulation of Cl− transport in the developing rabbit distal colon.Materials and Methods:Because serum contains growth factors, which could have confounded our studies, we first established an optimal milieu for testing EGF in primary cultures of adult rabbit distal colonocytes by culturing them for 24 h in media containing 0%, 1%, 5%, and 20% serum. Chloride transport (millimoles per second) and [Ca 2+] i were measured with use of the fluorescent indicator N-(ethoxycarbonylmethyl)-6-methoxyquinolinium bromide (MQAE) and Fura-2AM, respectively.Results:Serum depletion had no effect on cell number, DNA content, or basal Cl− transport, but it significantly affected cell viability. In media with 0%, 1%, or 20% serum, bethanechol, 8BrcAMP, taurodeoxycholate, and EGF stimulated Cl− transport to a similar extent. EGF maximally stimulated Cl− transport at 16.3 nmol/L and 20 minutes. Bethanechol, but not EGF, increased [Ca 2+] i. EGF did not alter bethanechol-stimulated Cl− transport or [Ca 2+] i. EGF acts via an EGF-receptor and mitogen activated protein kinase (MAPK) signaling pathway, since stimulation of Cl− transport was abolished by genistein, AG1478, and PD98059. Weanling and adult colonocytes, cultured in 1% serum, showed similar basal and EGF-stimulated Cl− transport.Conclusions:EGF stimulates rabbit colonic Cl− transport via a Ca 2+-independent, tyrosine kinase-and MAPK-dependent pathway, and its effects are not age dependent.