Powers R E, Grady T, Orchard J L, Gilrane T B
Department of Medicine, University of South Carolina School of Medicine.
Pancreas. 1993 Jan;8(1):58-63. doi: 10.1097/00006676-199301000-00012.
Cholecystokinin and its analogues such as cerulein, muscarinic cholinergic agonists, and gastrin-releasing peptide (bombesin) bind to distinct receptors on the surface of pancreatic acinar cells and stimulate digestive protein secretion by a calcium-dependent mechanism. The mechanisms of the calcium-dependent secretagogue classes has been assumed to be similar. In this study we have noted that dispersed pancreatic acini secrete comparable maximal rates of amylase in response to cerulein and bombesin; however, the maximal level of phosphatidylinositol 4,5-bisphosphate hydrolysis was less with bombesin than with cerulein. The high agonist dose-inhibited secretion in vitro observed with cerulein was absent with bombesin. In vivo administration of supramaximal secretory stimulating doses of both cerulein and bombesin caused pancreatic edema; however, the increase in serum concentrations of amylase and lipase induced by cerulein treatment was not detected with bombesin. These data indicate that cerulein and bombesin display distinctly different effects on the exocrine pancreas both in vivo and in vitro. That pancreatic edema and elevated serum enzyme levels may be the result of different cellular mechanisms in experimental pancreatitis is strongly suggested.
胆囊收缩素及其类似物，如蛙皮素、毒蕈碱型胆碱能激动剂和胃泌素释放肽（蛙皮素），与胰腺腺泡细胞表面不同的受体结合，并通过钙依赖机制刺激消化蛋白分泌。钙依赖型促分泌剂类别的作用机制被认为是相似的。在本研究中，我们注意到分散的胰腺腺泡对蛙皮素和蛙皮素的反应分泌出相当的最大淀粉酶速率；然而，蛙皮素引起的磷脂酰肌醇4,5 -二磷酸水解的最大水平低于蛙皮素。蛙皮素不存在蛙皮素在体外观察到的高激动剂剂量抑制分泌的情况。体内给予超最大分泌刺激剂量的蛙皮素和蛙皮素都会导致胰腺水肿；然而，蛙皮素治疗诱导的淀粉酶和脂肪酶血清浓度升高在蛙皮素治疗中未被检测到。这些数据表明，蛙皮素和蛙皮素在体内和体外对胰腺外分泌均表现出明显不同的作用。强烈提示胰腺水肿和血清酶水平升高可能是实验性胰腺炎中不同细胞机制的结果。
