Developmental regulation of epidermal growth factor receptor kinase in rat intestine.
Developmental regulation of epidermal growth factor receptor kinase in rat intestine.
复制标题
大鼠肠道表皮生长因子受体激酶的发育调节。
DOI：
10.1016/0016-5085(94)90528-2
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发表时间：
1994
期刊：
影响因子：
29.4
通讯作者：
Stokkers,PC
中科院分区：
文献类型：
--
作者：
Thompson,JF;vandenBerg,M;Stokkers,PC
背景/目的：腔内表皮生长因子（EGF）可以调节肠道生长和功能。研究了大鼠小肠中EGF受体的个体发育、定位和磷酸化。方法：体内给予EGF并体外培养囊外翻后，通过抗磷酸酪氨酸Western blot检测EGF受体的磷酸化。使用抗EGF受体抗体通过蛋白质印迹和免疫荧光测定EGF受体丰度和定位。结果：在体内，口胃EGF增强新生大鼠空肠和肝脏中EGF受体的磷酸化。然而，腔内 EGF 对成人肠道或肝脏中 EGF 受体的磷酸化没有影响。在体外，粘膜 EGF 刺激哺乳空肠中 EGF 受体磷酸化增加四倍，但在断奶婴儿或成年空肠中则不然。在蛋白质印迹中，22 日龄胎儿、8 日龄哺乳期和成人空肠中的 EGF 受体丰度相似。在隐窝和绒毛中，EGF受体定位于基底外侧膜，但在胎儿、哺乳期和成人空肠中不定位于顶膜。结论：粘膜EGF刺激未成熟肠中的EGF受体磷酸化，但不刺激成熟肠中的EGF受体磷酸化。这些差异不能用 EGF 受体丰度或定位来解释，表明未成熟肠道的粘膜通透性较大，可能允许 EGF 与基底外侧膜中的 EGF 受体结合，从而介导其在乳鼠肠道中的作用。
Background/Aims:Intraluminal epidermal growth factor (EGF) may regulate intestinal growth and function. The ontogeny, localization, and phosphorylation of the EGF receptor in rat small intestine were studied.Methods:EGF-receptor phosphorylation was assayed by antiphosphotyrosine Western blot after EGF administration in vivo and EGF incubation to everted sacs in vitro. EGF-receptor abundance and localization were assayed by Western blot and immunofluorescence using anti-EGF-receptor antibodies.Results:In vivo, orogastric EGF enhanced EGF-receptor phosphorylation in newborn rat jejunum and liver. However, intraluminal EGF had no effect on EGF-receptor phosphorylation in adult intestine or liver. In vitro, mucosal EGF stimulated a fourfold increase in EGF-receptor phosphorylation in suckling jejunum but not in weanling or adult jejunum. In Western blot, EGF-receptor abundance was similar in 22-day-old fetal, 8-day-old suckling, and adult jejunum. In both crypt and villus, EGF-receptor was localized to the basolateral membrane but not to the apical membrane in fetal, suckling, and adult jejunum.Conclusions:Mucosal EGF stimulates EGF-receptor phosphorylation in immature but not in mature intestine. These differences are not explained by EGF-receptor abundance or localization and suggest that the greater mucosal permeability of the immature gut may allow EGF to bind to the EGF-receptor in the basolateral membrane to mediate its effects in suckling rat intestine.