Li L, Yu Z, Piascik R, Hetzel D P, Rourk R M, Namiot Z, Sarosiek J, McCallum R W
University of Virginia Health Sciences Center, Charlottesville.
Am J Gastroenterol. 1993 Oct;88(10):1749-55.
Although various animal and clinical studies have demonstrated the significant effect of salivary epidermal growth factor (sEGF) on esophageal morphology and function, its secretory patterns still remain inadequately explored. Therefore, we have studied the impact of esophageal mechanical and chemical stimuli on sEGF in humans. sEGF was measured in saliva collected during basal conditions, chewing of parafilm, placement of esophageal tubing, inflation of intraesophageal balloons, and perfusion with NaCl, HCl, and HCl/pepsin solutions. The concentration of sEGF was measured with a radioimmunoassay kit from Amersham (Arlington Heights, IL). The concentration of sEGF in basal saliva was (mean +/- SEM) 2.08 +/- 0.22 ng/ml. Chewing the parafilm resulted in a significant decline of sEGF concentration to the value of 1.39 +/- 0.16 ng/ml (p < 0.0005). Similar decline in sEGF concentration also prevailed after placement of intraesophageal tubing (p < 0.03), and inflation of intraesophageal balloons (p < 0.01). This decline intensified significantly when prolonged esophageal perfusion with saline was implemented (p < 0.03 vs. tubing). Substitution of NaCl with HCl in the second and third perfusion periods prevented the decline in sEGF concentration, whereas HCl accompanied by pepsin enhanced sEGF concentration. The rate of sEGF output was 0.90 +/- 0.13 ng/min during basal conditions and increased significantly during parafilm chewing (1.53 +/- 0.25 ng/min; p < 0.05). However, sEGF secretion during both placement of esophageal tubing and inflation of balloons increased 4.1- and 4.9-fold, respectively (p < 0.002 and < 0.00005), over the basal value, and 2.4- and 2.9-fold, respectively, over the parafilm stimulated secretion. Subsequently, we observed a further significant decline of sEGF output (p < 0.05) which was sustained during perfusion of the esophagus with saline. Interestingly, esophageal perfusion with HCl prevented the decline of sEGF secretion observed during perfusion with saline. sEGF output during esophageal perfusion with HCl/pepsin exhibited a strong increase, reaching the value of 5.86 +/- 0.70 ng/ml. This value corresponds to a 58% increase over the secretory rate observed during mechanical stimulation by placement of esophageal tubing (3.71 +/- 0.47; p < 0.05). HCl/pepsin-induced potentiation of sEGF secretion was also highly significantly increased over both the value recorded during basal (p < 0.0005) and parafilm-stimulated (p < 0.002) conditions. Subsequent substitution of HCl/pepsin solution with a final saline perfusate still maintained enhanced sEGF output, compared with both basal (p < 0.02) and parafilm-stimulated conditions (p < 0.02).(ABSTRACT TRUNCATED AT 400 WORDS)
尽管各种动物和临床研究已证明唾液表皮生长因子（sEGF）对食管形态和功能有显著影响，但其分泌模式仍未得到充分研究。因此，我们研究了食管机械和化学刺激对人体sEGF的影响。在基础状态、咀嚼石蜡膜、放置食管导管、充气食管气囊以及用氯化钠、盐酸和盐酸/胃蛋白酶溶液灌注期间收集的唾液中测量sEGF。使用来自Amersham（伊利诺伊州阿灵顿高地）的放射免疫分析试剂盒测量sEGF的浓度。基础唾液中sEGF的浓度为（平均值±标准误）2.08±0.22 ng/ml。咀嚼石蜡膜导致sEGF浓度显著下降至1.39±0.16 ng/ml（p<0.0005）。放置食管导管（p<0.03）和充气食管气囊（p<0.01）后，sEGF浓度也出现类似下降。当长时间用盐水灌注食管时，这种下降显著加剧（与导管放置相比，p<0.03）。在第二和第三灌注期用盐酸替代氯化钠可防止sEGF浓度下降，而盐酸与胃蛋白酶一起则提高了sEGF浓度。基础状态下sEGF的输出率为0.90±0.13 ng/分钟，在咀嚼石蜡膜期间显著增加（1.53±0.25 ng/分钟；p<0.05）。然而，放置食管导管和气囊充气期间sEGF的分泌分别比基础值增加了4.1倍和4.9倍（p<0.002和<0.00005），分别比石蜡膜刺激分泌增加了2.4倍和2.9倍。随后，我们观察到sEGF输出进一步显著下降（p<0.05），在用盐水灌注食管期间持续存在。有趣的是，用盐酸灌注食管可防止在用盐水灌注期间观察到的sEGF分泌下降。用盐酸/胃蛋白酶灌注食管期间sEGF输出显著增加，达到5.86±0.70 ng/ml。该值比放置食管导管机械刺激期间观察到的分泌率（3.71±0.47；p<0.05）增加了58%。盐酸/胃蛋白酶诱导的sEGF分泌增强也比基础状态（p<0.0005）和石蜡膜刺激状态（p<0.002）下记录的值显著增加。随后用最终的盐水灌注液替代盐酸/胃蛋白酶溶液，与基础状态（p<0.02）和石蜡膜刺激状态（p<0.02）相比，仍保持sEGF输出增强。（摘要截断于400字）
