Effect of renal failure or portacaval shunt on release of neurotensin in man.

Neurotensin-like immunoreactivity (NTLI) is released into the circulation following a meal. However, the factors influencing its degradation and metabolism are uncertain, but it is presumed that the kidneys and liver are involved. This study has determined the release of NTLI after a liquid fat meal (200 ml 20% Intralipid) in 10 healthy control subjects, five patients with stable chronic renal failure (CRF), and five patients after a portacaval shunt (PCS), to assess the possible role of the liver and kidney in NTLI metabolism. NTLI was measured by radioimmunoassay using both specific C and N terminally directed antisera. The results showed: Basal NTLI levels are similar in controls, after PCS, and in CRF. A liquid fat meal produces a single early peak of NTLI and levels are greater after PCS than in controls or CRF. Levels return much more slowly to basal in CRF and after PCS. Thus it is likely that both the liver and kidney are involved in the metabolism and clearance of NTLI.