The aim of this study was to investigate simultaneously the endogenously stimulated exocrine pancreatic secretion and the cholecystokinin (CCK) response in patients suffering from coeliac sprue. A Lundh-test was performed in nine patients and twenty-six healthy volunteers. Basal plasma-CCK levels (3.4 +/- 0.5 pmol/l in sprue patients vs. 4.1 +/- 0.5 pmol/l in controls) and the integrated 120 min postprandial CCK values showed no differences in both groups. However, in controls the peak CCK value of 27.5 +/- 5.6 pmol/l appeared after 15 minutes whereas in sprue patients the peak of 18.9 +/- 4.5 pmol/l appeared after 60 minutes. CCK concentrations in duodenal biopsies of patients with coeliac sprue revealed significantly lower values compared to controls (123.4 +/- 37.4 versus 240.0 +/- 11.3 pmol/g wet weight). The stimulated lipase output was significantly lower throughout the whole sampling period in coeliac sprue patients whereas amylase output showed an inconstant reduction. The trypsin output was not altered. These results suggest that other mediators than CCK are responsible for the maintenance of trypsin output and for the reduction of lipase output in patients with coeliac sprue.