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This study was undertaken to answer two questions: (a) does antrectomy disturb sieving or grinding of solid food, or both, and (b) how abnormal are jejunal flows and concentrations of pancreatic enzymes and bile salts after a meal of solid food. Six normal subjects and 9 subjects with truncal vagotomy plus antrectomy were intubated with a triple-lumen tube attached to a bubble trap sited in the jejunum, 60 cm from the stomach. All subjects ate a meal of 100 ml of H2O, 60 g of beefsteak, and 30 g of 99mTc-liver diced into 10-mm cubes. By previously validated techniques, the tube-bubble trap system allowed comparison of the rate of passage of 99mTc-liver particles smaller than 1 mm through the jejunum with the rate of entry of all sizes of eaten 99mTc-liver into the intestine described by gamma camera. The tube system also measured concentrations and rates of passage of enzymes and bile salts. 99mTc-liver emptied very rapidly from the stomach in the first 50 min in most subjects with truncal vagotomy plus antrectomy and thereafter emptied slowly, while in the normal subjects there was a 30 min lag before a steady, slow rate of emptying. Nearly 30% of the 99mTc-liver that emptied into the intestine in the subjects with truncal vagotomy plus antrectomy was larger than 1 mm, but in the normal subjects less than 3% of the liver entered the intestines as larger particles. In this study with a solid meal, jejunal flows in the subjects with truncal vagotomy plus antrectomy were lower than normal, and concentrations of bile salts and pancreatic enzymes were close to normal.

Alterations in gastric emptying are considered contributory to many sequelae of peptic ulcer surgery. The application of a validated method of firmly tagging solid food has enabled the measurement of the rates and patterns of gastric emptying in normal subjects, subtotal gastrectomy, and vagotomy and pyloroplasty (VP (2) rapid emptying with exponential pattern and mean rate constant of 0.039 min−1, t1/2 of 17.7 min. The slow gastric emptying rate and slow passage of chyme through the small intestine in one-half of the V&P group presumably allows greater efficiency of digestion and absorption and may account for the over-all less severe nutritional disturbances after V&P.

Prior attempts at in vivo reversible vagal denervation of the gastrointestinal tract have been limited to cervical cooling techniques that also denervate both sympathetic and vagal pulmonary and cardiac branches. Denervation of vagal efferent fibers at this level has produced results that are inconsistent with those obtained after surgical truncal vagotomy. We have, therefore, developed a technique to provide reversible vagal denervation below the pulmonary and cardiac branches for the study of gastric motility. Five dogs, previously equipped with gastric strain gages and electrodes, underwent implantation of a tubular cooling jacket around a distal thoracic vagal trunk with contralateral vagotomy (4 dogs), or around both vagal trunks (1 dog). The jacket was made of stainless steel tubing in a "J" design. Its inside channel was lined with a sterling silver sheet, and a thermistor was attached to record temperature change. Silicone tubing coursed externally to a pump and flask to which 95% ethanol at -70 degrees C was circulated at variable speeds. Thoracic vagal cooling, extending up to 5 h, reversibly blocked gastric contractions induced by insulin hypoglycemia. Contractile waves were terminated at device temperatures of 2 degrees-6 degrees C but promptly returned with warming. Dogs were tranquil during denervation, and enclosed nerves remained functional for greater than 40 days.

Gastric emptying of solid egg meals tagged with 99mtechnetium sulfur colloid was studied in 10 normal subjects and in 6 patients after truncal vagotomy, antrectomy, and gastrojejunostomy (Billroth II) for peptic ulcer disease. Technetium sulfur colloid was found to bind more firmly to cooked egg whites than did the water soluble marker DTPA. Water accelerated gastric empyting in Billroth II patients to a greater degree than in normal subjects, in whom the effect of water was minimal and transient. Fat inhibited solid emptying both in normals and in Billroth II patients. These findings suggest that in humans there are jejunal receptors for fat that may inhibit gastric emptying even following truncal vagotomy.

We have demonstrated that at doses lower than those used by others in dogs, atropine consistently inhibited food-stimulated gastrin release irrespective of vagal innervation of the stomach. Gastrin release induced by food placed directly into the stomach was studied in four gastric fistula dogs with intact vagi and in three other similar dogs with fundic vagotomy. The studies were repeated in the dogs after conversion to truncal vagotomy. Fasting serum gastrin was lower in the intact dogs (33 ± 1.7 pg/ml) than after fundic vagotomy (61 ± 13 pg/ml) or truncal vagotomy (97 ± 20 pg/ml). The same relationship held for absolute postprandial values. However, the integrated gastrin response to food over 2 h was similar in the three groups of dogs (intact 14 ± 4.6, fundic vagotomy 10.3 ± 4.3, truncal vagotomy 17.4 ± 2.4 ng min/ml). Regardless of the state of gastric vagal innervation atropine 20 μg/kg · h reduced gastrin release due to food by 66–76% (p 50 of 5.1 μg/kg or 7.2 × 10 -9 mol/kg. Findings of this study indicate a previously undescribed muscarinic cholinergic pathway leading to gastrin release by food.

Reproducibility of the insulin response has been tested in 50 peptic ulcer patients with regard to the time after insulin at which the response occurred. The response was found to be reproducibile to within 15 min of initial timing in patients with intact vagus nerves, in patients within 1 month following truncal vagotomy with a simple drainage procedure, and in a small group of patients 1 to 7 years after vagotomy and drainage. Comparison of basal acid secretion and acid output after insulin revealed no significant differences between the paired tests.

Using the arbitrary criteria of Hollander, the results of insulin tests in the 2nd week after truncal vagotomy and either gastrojejunostomy or pyloroplasty have been compared with repeat insulin tests in the same patients 3 months to 4 years later. Approximately 50% of those with negative responses at the initial postoperative tests were found to have positive responses at the follow-up tests. There was also a tendency for those with borderline positive responses at the first test to show greater, earlier positive responses at the repeat tests. The findings support the desirability of delaying insulin assessment of postvagotomy patients until several months after operation.

Changes in serum gastrin in response to feeding a meal of beef liver (15 g kg−1) were studied in 5 gastric fistula dogs with and without administration of atropine sulfate (0.2 mg kg−1 intravenously). The studies were repeated after a truncal vagotomy that abolished acid secretion in response to 2-deoxyglucose. Before vagotomy atropine had little effect on the gastrin response to a meal. After vagotomy the gastrin response to feeding was greatly enhanced, but now atropine depressed the gastrin response at all times after the meal. It is concluded that vagotomy enhances the serum gastrin response to feeding and that atropine counteracts this enhancement.