Plasma cholecystokinin response to oral fat in patients with Billroth I and Billroth II gastrectomy.

The present study was undertaken to determine whether bypassing the duodenum in patients with Billroth II gastrectomy affects plasma cholecystokinin (CCK) release in response to ingestion of fat. Plasma CCK concentrations were measured by radioimmunoassay using two antibodies; antibody 1703 binds to all carboxyl-terminal CCK-peptides containing at least 14 amino acid residues, while antibody T204 is specific for the sulphated tyrosine region of CCK. There were no significant differences among fasting plasma CCK concentrations in seven patients with Billroth II gastrectomy (1.3 +/- 0.4 fmol/ml, antibody 1703; 2.6 +/- 0.4 fmol/ml, antibody T204), six patients with Billroth I gastrectomy (0.6 +/- 0.3 fmol/ml, antibody 1703; 2.9 +/- 0.5 fmol/ml, antibody T204), and nine normal subjects (0.7 +/- 0.1 fmol/ml, antibody 1703; 1.9 +/- 0.3 fmol/ml, antibody T204). Ingestion of 250 ml 20% Intralipid induced similar increases in plasma CCK in patients with Billroth II gastrectomy (11.2 +/- 2.0 fmol/ml, antibody 1703; 10.1 +/- 2.4 fmol/ml, antibody T204) as in patients with Billroth I gastrectomy (11.8 +/- 2.0 fmol/ml, antibody 1703; 8.4 +/- 1.1 fmol/ml, antibody T204). However, the increments in plasma CCK in patients with gastrectomy (11.5 +/- 1.4 fmol/ml, antibody 1703; 9.3 +/- 1.4 fmol/ml, antibody T204) were significantly (p less than 0.01) greater than those in normal subjects (4.7 +/- 0.8 fmol/ml, antibody 1703; 4.1 +/- 0.7 fmol/ml). Similarly, the integrated plasma CCK secretion in patients with Billroth II gastrectomy (510 +/- 58 fmol/ml X 120 min, antibody 1703; 458 +/- 69 fmol/ml X 120 min, antibody T204) and in patients with Billroth I gastrectomy (457 +/- 143 fmol/ml X 120 min, antibody 1703; 365 +/- 61 fmol/ml X 120 min, antibody T204) were significantly (p less than 0.05) greater than in normal subjects (230 +/- 49 fmol/ml X 120 min, antibody 1703; 162 +/- 24 fmol/ml X 120 min, antibody T204). It is concluded that the plasma CCK response to oral fat is significantly greater in patients with partial gastrectomy than in normal subjects, and that patients with Billroth I and Billroth II gastrectomy have similar increases in plasma CCK after ingestion of fat.