TY - JOUR
T1 - Rectal distension inhibits postprandial small intestinal motor activity partially via the adrenergic pathway in dogs
AU - Qi, Huibin
AU - Brining, Doug
AU - Chen, Jiande D.Z.
PY - 2007
Y1 - 2007
N2 - Objective. Rectal distension is known to induce numerous upper gastrointestinal symptoms. The aim of this study was to investigate the effects and mechanisms of rectal distension on small intestinal myoelectrical and motor activities in 8 dogs using a pair of intestinal electrodes and an intestinal fistula. Material and methods. Experiment 1 entailed a 30-min baseline recording and a 30-min recording during rectal balloon distension at various volumes (60, 80, 100 and 120 ml) randomly. Experiment 2 comprised three sessions, each including a 30-min baseline recording, a 20-min recording after intravenous infusion of saline, phentolamine (3 mg/kg) or propranolol (3 mg/kg), respectively, and another 30-min recording during rectal balloon distending. Results. 1) Rectal distension resulted in reduced intestinal motility in a dose-dependent manner (r=0.68, p<0.001). 2) The reduction in intestinal motility was significantly diminished when infusions of phentolamine (2.7±1.0 versus 8.4±1.5, p<0.01) or propranolol (3.7±1.4 versus 8.4±1.5, p<0.05) were given, suggesting partial involvement of the alpha- and beta-adrenergic pathways. 3) Rectal distension did not affect the percentage of normal 17-22 cycles/min intestinal slow waves (97.5±2.5 versus 93.0±5.3, p>0.05), or their dominant frequency (17.2±1.2 counts per minute (cpm) versus 17.7±1.0 cpm, p>0.05), or dominant power (-4.8±2.5 versus -8.2±2.9 dB, p>0.05). Conclusions. Rectal distension inhibits postprandial small intestinal motor activity in a distension volume-dependent manner in dogs, and this inhibitory effect is at least partially mediated via the alpha and beta adrenergic pathways and does not involve any alterations in intestinal slow waves.
AB - Objective. Rectal distension is known to induce numerous upper gastrointestinal symptoms. The aim of this study was to investigate the effects and mechanisms of rectal distension on small intestinal myoelectrical and motor activities in 8 dogs using a pair of intestinal electrodes and an intestinal fistula. Material and methods. Experiment 1 entailed a 30-min baseline recording and a 30-min recording during rectal balloon distension at various volumes (60, 80, 100 and 120 ml) randomly. Experiment 2 comprised three sessions, each including a 30-min baseline recording, a 20-min recording after intravenous infusion of saline, phentolamine (3 mg/kg) or propranolol (3 mg/kg), respectively, and another 30-min recording during rectal balloon distending. Results. 1) Rectal distension resulted in reduced intestinal motility in a dose-dependent manner (r=0.68, p<0.001). 2) The reduction in intestinal motility was significantly diminished when infusions of phentolamine (2.7±1.0 versus 8.4±1.5, p<0.01) or propranolol (3.7±1.4 versus 8.4±1.5, p<0.05) were given, suggesting partial involvement of the alpha- and beta-adrenergic pathways. 3) Rectal distension did not affect the percentage of normal 17-22 cycles/min intestinal slow waves (97.5±2.5 versus 93.0±5.3, p>0.05), or their dominant frequency (17.2±1.2 counts per minute (cpm) versus 17.7±1.0 cpm, p>0.05), or dominant power (-4.8±2.5 versus -8.2±2.9 dB, p>0.05). Conclusions. Rectal distension inhibits postprandial small intestinal motor activity in a distension volume-dependent manner in dogs, and this inhibitory effect is at least partially mediated via the alpha and beta adrenergic pathways and does not involve any alterations in intestinal slow waves.
KW - Adrenergic pathway
KW - Gastrointestinal motility
KW - Rectal distension
KW - Slow waves
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U2 - 10.1080/00365520601127257
DO - 10.1080/00365520601127257
M3 - Article
C2 - 17558903
AN - SCOPUS:34250171162
SN - 0036-5521
VL - 42
SP - 807
EP - 813
JO - Scandinavian Journal of Gastroenterology
JF - Scandinavian Journal of Gastroenterology
IS - 7
ER -