el-Shahawy M A, Fadda G Z, Wisner J R, Renner I G, Omachi H, Massry S G
Department of Medicine, University of Southern California School of Medicine, Los Angeles.
Nephron. 1991;57(1):69-74. doi: 10.1159/000186219.
Chronic renal failure is associated with structural and functional abnormalities of the exocrine system of the pancreas. Certain data suggest that the excess parathyroid hormone (PTH) in these patients may participate in the genesis of these pancreatic derangements. However, direct evidence that PTH exerts a direct effect on the exocrine pancreatic system is not well documented. The present study examined the effects of the intact molecule (1-84 PTH) and of the amino-terminal fragment (1-34 PTH) of the hormone on the basal output of pure pancreatic juice (PPJ) volume and pancreatic protein secretion in the rat. 1-84 PTH but not 1-34 PTH significantly (p less than 0.01) stimulated the output of PPJ volume without an effect on protein secretion. The magnitude of this stimulatory effect of 1-84 PTH depended on the dose of the hormone administered, and it was related to its biological activity, since inactivation of PTH abolished its action on the output of PPJ volume. The simultaneous administration of the calcium channel blocker, verapamil, reduced but did not abolish the stimulatory effect of PTH on the volume of PPJ output. The data demonstrate that: (1) the ductal cells of the pancreatic acini are targets for PTH and (2) the action of the hormone on these cells is mediated, at least in part, via PTH-induced entry of calcium into the target cells.
慢性肾衰竭与胰腺外分泌系统的结构和功能异常有关。某些数据表明，这些患者体内过量的甲状旁腺激素（PTH）可能参与了这些胰腺紊乱的发生。然而，PTH对胰腺外分泌系统产生直接作用的直接证据尚未得到充分证实。本研究检测了该激素的完整分子（1-84 PTH）和氨基末端片段（1-34 PTH）对大鼠纯胰液（PPJ）分泌量和胰腺蛋白质分泌基础量的影响。1-84 PTH而非1-34 PTH显著（p<0.01）刺激了PPJ的分泌量，而对蛋白质分泌无影响。1-84 PTH这种刺激作用的强度取决于所给予激素的剂量，并且与它的生物活性有关，因为PTH失活会消除其对PPJ分泌量的作用。同时给予钙通道阻滞剂维拉帕米可降低但不能消除PTH对PPJ分泌量的刺激作用。这些数据表明：（1）胰腺腺泡的导管细胞是PTH的作用靶点；（2）该激素对这些细胞的作用至少部分是通过PTH诱导钙离子进入靶细胞介导的。
