Mårvik R, Johnsen A H, Rehfeld J F, Sandvik A, Waldum H L
Dept. of Surgery, Trondheim University Hospital, Norway.
Scand J Gastroenterol. 1994 Jul;29(7):591-4. doi: 10.3109/00365529409092477.
The protochordean octapeptide cionin is structurally a hybrid of mammalian cholecystokinin (CCK) and gastrin. An earlier study has shown that cionin in mammals stimulates gallbladder contraction and gastric somatostatin release, similarly to CCK-8.
In the present study we examined the effect of cionin on histamine release and acid secretion of the stomach, both effects being mediated by CCK-B/gastrin receptors.
Cionin induced a concentration-dependent increase in histamine release and acid secretion in the isolated, vascularly perfused rat stomach, detectable at a concentration of 4 pM and reaching a maximum at a concentration of 512 pM. The CCK-B/gastrin receptor antagonist L 365,260 abolished the stimulating effect of cionin on both histamine release and acid secretion, whereas the CCK-A receptor antagonist L 364,718 only had a faint effect.
Cionin is a potent and efficient stimulator of gastric histamine release and acid secretion interacting via a CCK-B receptor.
原索动物八肽海鞘素在结构上是哺乳动物胆囊收缩素（CCK）和胃泌素的杂合体。一项早期研究表明，哺乳动物体内的海鞘素能刺激胆囊收缩和胃生长抑素释放，这与CCK - 8类似。
在本研究中，我们检测了海鞘素对胃组胺释放和胃酸分泌的影响，这两种效应均由CCK - B/胃泌素受体介导。
在离体、血管灌流的大鼠胃中，海鞘素能诱导组胺释放和胃酸分泌呈浓度依赖性增加，在浓度为4 pM时即可检测到，在浓度为512 pM时达到最大值。CCK - B/胃泌素受体拮抗剂L 365,260消除了海鞘素对组胺释放和胃酸分泌的刺激作用，而CCK - A受体拮抗剂L 364,718仅有微弱作用。
海鞘素是一种强效且有效的胃组胺释放和胃酸分泌刺激剂，通过CCK - B受体发挥作用。
