Zawalich W S, Zawalich K C, Rasmussen H
Yale University School of Nursing, New Haven, Conn.
Diabetologia. 1989 Jun;32(6):360-4. doi: 10.1007/BF00277259.
The effect of monooleoylglycerol on cholecystokinin- and tolbutamide-induced insulin secretion was examined in isolated perifused rat islets. In the presence of 5.5 mmol/l glucose, addition of 10 nmol/l cholecystokinin or 50 mumol/l tolbutamide had practically no effect on insulin secretion. Combined tolbutamide and cholecystokinin led to a biphasic insulin secretory response which was significantly enhanced by addition of 50 mumol/l monooleoylglycerol, an inhibitor of diacylglycerol kinase. Monooleoylglycerol (50 mumol/l) alone had a minimal stimulatory effect on insulin release in the presence of 5.5 mmol/l glucose. Perifusion of islets with 1 mumol/l forskolin had no significant effect on basal insulin secretion in the presence of 5.5 mmol/l glucose, but markedly enhanced the responses to both cholecystokinin plus tolbutamide, and to the combination of cholecystokinin, tolbutamide and monooleoylglycerol. Lowering the glucose level to 2.75 mmol/l abolished the profound stimulatory effect to these agonist combinations on insulin release. Finally, monooleoylglycerol also enhanced the first and second phase insulin secretory responses induced by 20 mmol/l glucose. These results are discussed in relationship to the possible role of protein kinase C in mediating insulin secretion.
在分离的灌注大鼠胰岛中研究了单油酸甘油酯对胆囊收缩素和甲苯磺丁脲诱导的胰岛素分泌的影响。在5.5 mmol/l葡萄糖存在的情况下，添加10 nmol/l胆囊收缩素或50 μmol/l甲苯磺丁脲对胰岛素分泌几乎没有影响。甲苯磺丁脲和胆囊收缩素联合使用导致双相胰岛素分泌反应，添加50 μmol/l单油酸甘油酯（二酰基甘油激酶抑制剂）可显著增强该反应。在5.5 mmol/l葡萄糖存在的情况下，单独使用50 μmol/l单油酸甘油酯对胰岛素释放的刺激作用最小。在5.5 mmol/l葡萄糖存在的情况下，用1 μmol/l福斯高林灌注胰岛对基础胰岛素分泌没有显著影响，但显著增强了对胆囊收缩素加甲苯磺丁脲以及对胆囊收缩素、甲苯磺丁脲和单油酸甘油酯组合的反应。将葡萄糖水平降至2.75 mmol/l消除了这些激动剂组合对胰岛素释放的强烈刺激作用。最后，单油酸甘油酯还增强了由20 mmol/l葡萄糖诱导的第一相和第二相胰岛素分泌反应。结合蛋白激酶C在介导胰岛素分泌中的可能作用对这些结果进行了讨论。
