Hermansen K, Lindskog S, Ahrén B
Department of Endocrinology, Arhus University Hospital, Denmark.
Int J Pancreatol. 1996 Oct;20(2):103-7. doi: 10.1007/BF02825508.
3-O-methylglucose stimulates somatostatin secretion from the dog pancreas by a glucose-dependent and glucose-like effect. Therefore, it is possible that 3-O-methylglucose-stimulated somatostatin secretion is dependent on glucose metabolism.
Somatostatin secretion from the endocrine pancreas is stimulated by glucose, glyceraldehyde, and dihydroxyacetone but not affected by fructose, galactose, or ribose. Whether the nonmetabolizable glucose analog, 3-O-methylglucose affects somatostatin secretion is, however, not known.
We therefore, examined whether the glucose analog affects somatostatin secretion in the perfused dog pancreas.
We found that when added to a medium containing 2.7 mM or 5.5 mM D-glucose, 3-O-methylglucose (10 mM) stimulated somatostatin secretion to the same extent as did an equivalent dose of D-glucose. The same stimulation was observed also with arginine at 2.5 mM in the perfusion medium. In contrast, 3-O-methylglucose did not stimulate somatostatin secretion in the absence of glucose in the perfusion medium. Mannoheptulose (5 mM), which inhibits glucose metabolism, completely blocked the secretion to both hexoses.
3 - O - 甲基葡萄糖通过葡萄糖依赖性和类葡萄糖效应刺激犬胰腺分泌生长抑素。因此,3 - O - 甲基葡萄糖刺激的生长抑素分泌可能依赖于葡萄糖代谢。
内分泌胰腺分泌生长抑素受葡萄糖、甘油醛和二羟基丙酮刺激,但不受果糖、半乳糖或核糖影响。然而,不可代谢的葡萄糖类似物3 - O - 甲基葡萄糖是否影响生长抑素分泌尚不清楚。
因此,我们研究了这种葡萄糖类似物是否影响灌注犬胰腺中生长抑素的分泌。
我们发现,当添加到含有2.7 mM或5.5 mM D - 葡萄糖的培养基中时,3 - O - 甲基葡萄糖(10 mM)刺激生长抑素分泌的程度与等量的D - 葡萄糖相同。在灌注培养基中加入2.5 mM精氨酸时也观察到相同的刺激作用。相反,在灌注培养基中不存在葡萄糖的情况下,3 - O - 甲基葡萄糖不刺激生长抑素分泌。抑制葡萄糖代谢的甘露庚酮糖(5 mM)完全阻断了两种己糖的分泌。