Neurotensin and substance P and dumping syndrome.

To investigate the pathophysiological relation between releases of gut hormones and dumping syndrome, plasma radioimmunoassayable neurotensin, substance P, glucagon-like immunoreactivity (GLI), insulin and blood sugar were measured in both gastrectomized patients and control subjects after 50 g oral glucose tolerance tests. Remarkable rises of radioimmunoassayable neurotensin and GLI were found in all gastrectomized patients, but not in control subjects. In contrast, plasma radioimmunoassayable substance P responses were not detected in either gastrectomized patients or control subjects. There were three patients with symptoms of dumping syndrome in the early stage of the test. Plasma radioimmunoassayable neurotensin responses in two out of these three were higher than those in other patients, though the other patient with symptoms had the same degree of neurotensin elevation as patients with no symptoms. In view of the pharmacological effects of neurotensin, it could not be ruled out that a part of the early symptoms of dumping syndrome may result from the remarkably enhanced plasma neurotensin release in some patients, although the enhanced neurotensin responses did not always accompany symptoms of dumping syndrome.