TY - JOUR
T1 - Selective Role of Vagal and Nonvagal Innervation in Initiation and Coordination of Gastric and Small Bowel Patterns of Interdigestive and Postprandial Motility
AU - Tanaka, Toshiyuki
AU - VanKlompenberg, Luke H.
AU - Sarr, Michael G.
N1 - Funding Information:
From the Gastroenterology Research Unit, Mayo Clinic, Rochester, Minn. Supported in part by United States Public Health Service grant DK 39337 from the National Institutes of Health (M.G.S.) and by the Mayo Foundation. Presented at the Forty-First Annual Meeting of The Society for Surgery of the Alimentary Tract, San Diego, Calif., May 2 l-24,2000 (Poster presentation), and published as an abstract in Gustroenterology 118:AlOSO,2 000. Reprint requests: Michael G. Sarr, M.D., Gastroenterology Research Unit, Mayo Clinic, 200 First Street SW, Rochester, MN 55905.
PY - 2001
Y1 - 2001
N2 - Our previous studies suggested that extrinsic innervation modulates upper gut motility but is not requisite for cyclic interdigestive and postprandial motility of the stomach. However, the specific role of vagal and nonvagal extrinsic innervation in the initiation, coordination, and pattern of gastric motility in dogs after denervation of the entire upper gastrointestinal tract remains unclear. The aim of this study was to determine the role of vagal and nonvagal extrinsic innervation in control of gastric motility patterns. Mongrel dogs were subjected first to extrinsic denervation (in situ neural isolation) of the stomach, small bowel, proximal colon, liver, and pancreas but specifically maintaining vagal innervation to the stomach alone. After fasting and fed motility patterns were measured with indwelling gastric and small bowel manometry catheters, the dogs underwent transthoracic truncal vagotomy (completion of total extrinsic denervation of stomach), and motility studies were repeated. Vagal integrity to the stomach and pancreas was confirmed by means of a modified Hollander test and serum pancreatic polypeptide concentrations after the injection of exogenous insulin, respectively. We found that a cyclic motility pattern (migrating motor complex) persisted during fasting in both the stomach and the small bowel and that the patterns of the stomach and the duodenum remained temporally coordinated before and after vagotomy. However, although a cyclic phase in activity persisted in the stomach after vagotomy, the number of contractions and the motility index during phase III were decreased, and the duration between groupings of contractions was increased. No differences were noted in the duration of postprandial inhibition after feeding meals before and after vagotomy. These observations support our hypothesis that the vagal nerves are not necessary for the initiation or temporal coordination of global fasting or postprandial gastroduodenal motility patterns but are involved in modulating the pattern of contractions during gastric phase III.
AB - Our previous studies suggested that extrinsic innervation modulates upper gut motility but is not requisite for cyclic interdigestive and postprandial motility of the stomach. However, the specific role of vagal and nonvagal extrinsic innervation in the initiation, coordination, and pattern of gastric motility in dogs after denervation of the entire upper gastrointestinal tract remains unclear. The aim of this study was to determine the role of vagal and nonvagal extrinsic innervation in control of gastric motility patterns. Mongrel dogs were subjected first to extrinsic denervation (in situ neural isolation) of the stomach, small bowel, proximal colon, liver, and pancreas but specifically maintaining vagal innervation to the stomach alone. After fasting and fed motility patterns were measured with indwelling gastric and small bowel manometry catheters, the dogs underwent transthoracic truncal vagotomy (completion of total extrinsic denervation of stomach), and motility studies were repeated. Vagal integrity to the stomach and pancreas was confirmed by means of a modified Hollander test and serum pancreatic polypeptide concentrations after the injection of exogenous insulin, respectively. We found that a cyclic motility pattern (migrating motor complex) persisted during fasting in both the stomach and the small bowel and that the patterns of the stomach and the duodenum remained temporally coordinated before and after vagotomy. However, although a cyclic phase in activity persisted in the stomach after vagotomy, the number of contractions and the motility index during phase III were decreased, and the duration between groupings of contractions was increased. No differences were noted in the duration of postprandial inhibition after feeding meals before and after vagotomy. These observations support our hypothesis that the vagal nerves are not necessary for the initiation or temporal coordination of global fasting or postprandial gastroduodenal motility patterns but are involved in modulating the pattern of contractions during gastric phase III.
KW - Extrinsic denervation
KW - Migrating motor complex
KW - Motility
KW - Vagotomy
KW - Vagus nerves
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U2 - 10.1016/S1091-255X(01)80072-X
DO - 10.1016/S1091-255X(01)80072-X
M3 - Article
C2 - 11985985
AN - SCOPUS:0035412040
SN - 1091-255X
VL - 5
SP - 418
EP - 433
JO - Journal of Gastrointestinal Surgery
JF - Journal of Gastrointestinal Surgery
IS - 4
ER -