Harada E, Habara Y, Kanno T
Jpn J Physiol. 1984;34(1):167-80. doi: 10.2170/jjphysiol.34.167.
Influence of amino acids upon pancreatic exocrine secretion has been investigated in the isolated perfused pancreas of rats. Arg produced significant and dose-related inhibition of pancreatic juice flow, protein output and amylase output evoked by CCK-PZ (1.25 pM). The secretory response evoked by CCK-PZ was inhibited by other amino acids (Ala, Asp, Asn, Gly, Ile, Leu, Lys, Met, Phe, Pro, Thr, Trp, Val, in each 20 mM). A similar inhibitory pattern was observed using 10 mixed amino acids of 2 mM each (Pro, Phe, Thr, Met, Lys, Asp, Leu, Trp, Val, Gly). Gly at a concentration of 20 mM produced significant inhibition of exocrine secretion evoked by ACh (50 nM) or GRP (36 pM). The inhibitory response induced by amino acids could not be repeated by using exogenous insulin (1 microM) and glucagon (280 nM). The inhibitory response was also not changed by increased extracellular Ca (5 or 10 mM). However, Gly (20 mM) produced inhibition of exocrine secretion evoked by Ca reintroduction into a pancreas which was pretreated with A 23187. It was suggested that the inhibitory effects of some amino acids on exocrine secretion are mainly caused by suppression of Ca influx in a stimulus-secretion coupling process.
已在大鼠离体灌注胰腺中研究了氨基酸对胰腺外分泌的影响。精氨酸对胆囊收缩素-胰酶泌素（CCK-PZ，1.25 pM）诱发的胰液分泌、蛋白质分泌和淀粉酶分泌产生显著且与剂量相关的抑制作用。其他氨基酸（丙氨酸、天冬氨酸、天冬酰胺、甘氨酸、异亮氨酸、亮氨酸、赖氨酸、蛋氨酸、苯丙氨酸、脯氨酸、苏氨酸、色氨酸、缬氨酸，各20 mM）也抑制CCK-PZ诱发的分泌反应。使用10种各2 mM的混合氨基酸（脯氨酸、苯丙氨酸、苏氨酸、蛋氨酸、赖氨酸、天冬氨酸、亮氨酸、色氨酸、缬氨酸、甘氨酸）时观察到类似的抑制模式。20 mM浓度的甘氨酸对乙酰胆碱（50 nM）或胃泌素释放肽（36 pM）诱发的外分泌产生显著抑制作用。使用外源性胰岛素（1 microM）和胰高血糖素（280 nM）无法重现氨基酸诱导的抑制反应。细胞外钙浓度增加（5或10 mM）时，抑制反应也未改变。然而，甘氨酸（20 mM）对用A 23187预处理的胰腺重新引入钙后诱发的外分泌产生抑制作用。研究表明，某些氨基酸对外分泌的抑制作用主要是由刺激-分泌偶联过程中钙内流的抑制引起的。
