[Radioimmunological determination of plasma VIP and serum gastrin concentrations as affected by nutrition].

In 10 volunteers, the plasma VIP and serum gastrin concentrations before and after a test meal were measured at thirty minute intervals over a period of 5 hours. The precision of the VIP radioimmunoassay (double antibody method) is indicated by a coefficient of variation of 6%; its accuracy is reflected by the percentage deviation in the dilution test of between 0.6 and 8.5%. There was no significant difference in VIP concentrations before and after consumption of the test meal (p less than 0.05), WILCOXON test). In contrast, the gastrin concentration had already risen significantly (p less than 0.01) after thirty minutes. It then dropped back to the fasting range over a period of 5 hours. The lack of a rise in VIP after ingestion of the test meal supports the contention that VIP is purely a neurotransmitter. In contrast, the test meal induced a luminal stimulation of G-cells with endocrine secretion.