Alino S F, Uvnäs-Morberg K
Department of Cell Biology and Morphology Science, University of Pais Vasco, Bilbao, Spain.
Acta Physiol Scand. 1989 Apr;135(4):565-71. doi: 10.1111/j.1748-1716.1989.tb08618.x.
The aim of the present investigation was to study how bombesin, gastrin-17, cholecystokinin-8 (CCK-8) and electrical vagal stimulation influence the release of gastrin and somatostatin into the gastric lumen. Bombesin (3 and 30 nmol kg-1 h-1), gastrin-17 and CCK-8 (10 nmol kg-1h-1) were infused i.v. and vagal stimulations at 5 V, 2 ms, 5 Hz were performed in anaesthetized rats, in which the stomach was perfused with a dextran solution (pH approximately 6 or approximately 1.5). pH, gastrin and somatostatin levels were measured in the perfusate after having passed the stomach. In addition, blood samples were drawn from the jugular vein in the experiments in which bombesin was infused. Gastrin and somatostatin levels were determined with radioimmunoassay, and gastrin- and somatostatin-like immunoreactivity will be referred to as gastrin and somatostatin below. Infusion of bombesin, 3 and 30 nmol kg-1 h-1, did not influence acid secretion as evidenced by an unchanged intraluminal pH. Nor was the intraluminal secretion of gastrin or somatostatin influenced by bombesin, whereas plasma gastrin and somatostatin levels were significantly increased at the higher dose. In contrast, infusion of CCK-8 and gastrin-17 (10 nmol kg-1 h-1), as well as electrical vagal stimulation, significantly decreased the pH and increased the somatostatin levels in the perfusate. Vagal activation in addition increased the gastrin levels. The present results, demonstrating that bombesin influences plasma and perfusate levels of gastrin and somatostatin differently, indicate that intraluminal and intravascular gastrin and somatostatin release may be separately regulated.
本研究的目的是探讨蛙皮素、胃泌素 -17、胆囊收缩素 -8（CCK -8）和迷走神经电刺激如何影响胃泌素和生长抑素释放到胃腔中。将蛙皮素（3和30 nmol kg⁻¹ h⁻¹）、胃泌素 -17和CCK -8（10 nmol kg⁻¹ h⁻¹）静脉输注，并在麻醉大鼠中进行5 V、2 ms、5 Hz的迷走神经刺激，这些大鼠的胃用葡聚糖溶液（pH约为6或约为1.5）灌注。在灌注液通过胃后测量灌注液中的pH、胃泌素和生长抑素水平。此外，在输注蛙皮素的实验中从颈静脉采集血样。用放射免疫分析法测定胃泌素和生长抑素水平，以下将胃泌素样和生长抑素样免疫反应性分别称为胃泌素和生长抑素。输注3和30 nmol kg⁻¹ h⁻¹的蛙皮素对酸分泌没有影响，腔内pH未改变即证明了这一点。蛙皮素也不影响胃泌素或生长抑素的腔内分泌，而在较高剂量时血浆胃泌素和生长抑素水平显著升高。相反，输注CCK -8和胃泌素 -17（10 nmol kg⁻¹ h⁻¹）以及迷走神经电刺激显著降低了灌注液的pH并提高了生长抑素水平。迷走神经激活还增加了胃泌素水平。本研究结果表明蛙皮素对胃泌素和生长抑素的血浆和灌注液水平影响不同，提示腔内和血管内胃泌素及生长抑素的释放可能是分别调节的。
