Mokuda O, Shibata M, Ooka H, Okazaki R, Sakamoto Y
Third Department of Internal Medicine,Teikyo University School of Medicine, Ichihara-City, Japan.
Diabetes Nutr Metab. 2002 Aug;15(4):260-4.
To study the role of B-cells in the regulation of glucagon secretion by glucose, the rat pancreas was perfused with 0.4 mmol/l diazoxide. Perfusate glucose was 5 mmol/l of a basal concentration, and then was decreased to 1 mmol/l, or was increased to 15 mmol/l. Insulin secretion was suppressed by diazoxide below the detectable level at each glucose concentration. Glucagon secretion was increased two-fold during the glucopenic perfusion without diazoxide, but was not changed at a low glucose concentration in the presence of diazoxide. During the glucose-excessive perfusion for 15 min, glucagon secretion was lowered from 0.69 +/- 0.17 pmol at 5 mmol/l glucose to 0.36 +/- 0.10 pmol at 15 mmol/l glucose (p < 0.05) without diazoxide, whereas that was inversely increased from 0.55 +/- 0.14 at 5 mmol/l glucose to 0.85 +/- 0.13 pmol at 15 mmol/l glucose (p < 0.05) in the presence of diazoxide. These results suggest that appropriate insulin secretion is necessary for the normal responses of glucagon secretion to hypoglycemia and hyperglycemia in the non-diabetic rat pancreas.
为研究B细胞在葡萄糖对胰高血糖素分泌调节中的作用，用0.4 mmol/l二氮嗪灌注大鼠胰腺。灌注液中葡萄糖的基础浓度为5 mmol/l，随后降至1 mmol/l或升至15 mmol/l。在每个葡萄糖浓度下，二氮嗪均将胰岛素分泌抑制至检测水平以下。在无二氮嗪的低血糖灌注期间，胰高血糖素分泌增加两倍，但在存在二氮嗪的低葡萄糖浓度下则无变化。在15分钟的高糖灌注期间，无二氮嗪时，胰高血糖素分泌从5 mmol/l葡萄糖时的0.69±0.17 pmol降至15 mmol/l葡萄糖时的0.36±0.10 pmol（p<0.05），而在存在二氮嗪时则相反，从5 mmol/l葡萄糖时的0.55±0.14升至15 mmol/l葡萄糖时的0.85±0.13 pmol（p<0.05）。这些结果表明，在非糖尿病大鼠胰腺中，适当的胰岛素分泌对于胰高血糖素分泌对低血糖和高血糖的正常反应是必要的。
