Meal-stimulated neurotensin immunoreactivity in plasma following gastric surgery: characterisation with two region-specific antisera.

Plasma neurotensin (NT) response to a simple fatty meal, administered via an indwelling naso-gastric tube, has been assessed in two groups of subjects following gastric surgery without resection, and in healthy controls. Two region-specific NT antisera were employed in the radioimmunoassay (RIA) of plasma samples. The first, NT3, recognises only NT 1-13 in plasma extracts, while the second, GNT 21, recognises NT 1-13, NT 1-11 and NT 1-8 equally. In addition, plasma extracts were subjected to reverse-phase high performance liquid chromatography, fractions from which were subjected to each region-specific RIA. There was no significant response to the test meal in the healthy controls. However, both groups of post-gastric surgery subjects, who had undergone either vagotomy and pyloroplasty (V & P) or vagotomy and gastrojejunostomy (V & GJ), displayed significant increases in both intact and N-terminal plasma NT immunoreactivity (IR). The integrated responses of the V & P and V & GJ groups were also significantly higher than the control response but did not differ significantly from one another. The proportion of intact NT to total N-terminal NT-IR in each group was not significantly different.