Jaworek J, Konturek S J
Institute of Physiology, University School of Medicine, Cracow, Poland.
J Physiol Pharmacol. 1993 Dec;44(4):365-81.
Exogenous eicosanoids were reported to affect pancreatic secretion, but it is unknown whether this effects is mediated by the changes in pancreatic circulation or by direct action on pancreatic secretory cells. In this study the effects of prostaglandins (PG), leukotriene C4 (LTC4) and platelet activating factor (PAF) and the blockers of their biosynthesis or receptor antagonists on amylase release from the isolated rat pancreatic acini were examined. The acini were incubated with pancreatic secretagogues, such as caerulein or urecholine in the presence or absence of various concentrations (10(-9)-10(-5) M) of PGE2, Nocloprost (stable analog of PGE2), PGI2, PGF1 alpha, LTC4, PAF, indomethacin (inhibitor of endogenous PG formation) and A-63162 (blocker of endogenous LT biosynthesis). PGE2, PGI2 and PGF1 alpha inhibited secretagogues-stimulated enzyme secretion from isolated pancreatic acini but their inhibitory potency was about 1000 times lower, on molar basis, than that of Nocloprost. PAF and LTC4 produced concentration-dependent stimulation of amylase release from the unstimulated acini reaching about 50% of caerulein-induced maximal response and enhanced amylase release induced by caerulein or urecholine. The effects of PAF and LTC4 were reversed by the addition of respective receptor antagonist for PAF (TCV-309) and for LTC4 (FPL-55712). These results indicate that PG inhibit, while PAF and LTC4 stimulate pancreatic enzyme secretion and thus could be implicated in the control of this secretion.
据报道，外源性类二十烷酸会影响胰腺分泌，但尚不清楚这种作用是由胰腺循环的变化介导，还是对胰腺分泌细胞的直接作用介导。在本研究中，检测了前列腺素（PG）、白三烯C4（LTC4）和血小板活化因子（PAF）及其生物合成阻滞剂或受体拮抗剂对分离的大鼠胰腺腺泡淀粉酶释放量的影响。将腺泡与胰腺促分泌剂（如蛙皮素或乌拉胆碱）一起孵育，同时存在或不存在不同浓度（10(-9)-10(-5)M）的PGE2、诺氯前列素（PGE2的稳定类似物）、PGI2、PGF1α、LTC4、PAF、吲哚美辛（内源性PG形成抑制剂）和A-63162（内源性LT生物合成阻滞剂）。PGE2、PGI2和PGF1α抑制促分泌剂刺激的分离胰腺腺泡的酶分泌，但按摩尔计算，它们的抑制效力比诺氯前列素低约1000倍。PAF和LTC4对未受刺激的腺泡淀粉酶释放产生浓度依赖性刺激，达到蛙皮素诱导的最大反应的约50%，并增强蛙皮素或乌拉胆碱诱导的淀粉酶释放。添加PAF（TCV-309）和LTC4（FPL-55712）各自的受体拮抗剂可逆转PAF和LTC4的作用。这些结果表明，PG抑制，而PAF和LTC4刺激胰腺酶分泌，因此可能参与这种分泌的控制。
