八种脑-肠肽侧脑室内注射对大鼠基础胃酸分泌的影响

用乌拉坦麻醉大鼠作急性实验,采用连续灌流胃并收集流出液的方法,观察向侧脑室内注射微量脑-肠肽对大鼠基础胃酸分泌的影响。实验结果如下:(1)雨蛙肽、八肽胆囊收缩素、促甲状腺素释放激素及四肽胃泌素均使总酸排出量增加;(2)生长抑素、胰多肽、P 物质、胰高血糖素则使总酸排出量减少;(3)上述肽类用侧脑室注射的剂量作肌肉注射,除四肽胃泌素也产生明显的刺激胃酸分泌作用外,对胃酸分泌均无明显影响。以上结果提示,脑内的一些肽类可能以神经递质或调制物的方式,参与中枢对胃酸分泌的调节。

EFFECT OF INTRACEREBRO-VENTRICULAR INJECTION OF SOME BRAIN-GUT PEPTIDES ON BASAL ACID SECRETION IN RATS

Anaesthetized rats with stomach continuously perfused with saline as describedby Ghosh and Schild were used.A small cannula was inserted into either one ofthe lateral cerebral ventricules and eight kinds of brain-gut peptides were injectedindividually through the cannula into the brain.Timed perfusates were collectedand titrated to pH 7 to quantify the change of acid secretion after each peptide wasgiven.The results were as follows:(1)The gastric acid secretion was significantlyincreased after intracerebro-ventricular injection of caerulein,cholecystokininoctapeptide(CCK-8),thyrotropin releasing hormone(TRH),or gastrin tetra-peptide(G-4).(2)Intracerebro-ventricular injection of substance P,pancreaticpolypeptide(PP),glucagon,or somatostatin,on the other hand,decreased gastricacid output.(3)No significant change of acid output was found when the abovepeptides in the same dosage were given intramuscularly except G-4,which causeda weak but still significant increase of acid secretion.The results suggest that some brain-gut peptides may through their centralaction take part in the regulation of gastric acid secretion.