[The effect of caerulein on gastric mucosal blood-flow and gastric secretion (author's transl)]

The effect of Caerulein, a decapeptide produced from the skin of the Australian frog Hyla caerulea, on the mucosal blood-flow and the gastric acid secretion as well as the pepsin secretion has been investigated in 15 patients. Caerulein administered at a dose rate of 0.1 mug/kg-h significantly inhibited the gastric mucosal blood-flow (p greater than 0.005) and the acid secretion (0.05 greater than p greater than 0.01), which had been stimulated by pentagastrin at a dose rate of 1.5 mug/kg-h. The pepsin secretion stimulated with pentagastrin also decreased, but not significantly. Caerulein at the above mentioned dose rate however caused a slight but not significant increase of the acid secretion stimulated by 40 mug histamine/kg-h. At the same time, gastric mucosal blood-flow and pepsin output decreased slightly but not significantly. Caerulein given alone stimulates acid secretion, yet it causes a significant reduction of the acid output when administered together with pentagastrin. This response has to be explained by the fact, that the similar chemical structure of pentagastrin and caerulein leads to a competitive inhibition. The mucosal blood-flow of the stomach measured with the heat-clearance technique also decreases with the administration of caerulein after pentagastrin stimulation. The fact that the mucosal blood-flow remains unchanged after the administration of histamine, suggests that the reduction in mucosal blood-flow observed with pentagastrin is a consequence and not the cause of the acid inhibition occurring at the same stage.