Published online Jul 14, 2013. doi: 10.3748/wjg.v19.i26.4214
Revised: May 2, 2013
Accepted: May 8, 2013
Published online: July 14, 2013
AIM: To study the effects of low-dose amitriptyline (AMT) on gastrointestinal function and brain-gut peptides in healthy Chinese volunteers.
METHODS: This was a double-blind, randomised, placebo-controlled, two-period cross-over trial. Twenty-eight healthy volunteers were randomised and administered 1-wk treatments of AMT (12.5 mg tid) or placebo. Before and during the final two days of treatment, gastric emptying, proximal gastric accommodation and visceral sensitivity were measured by drinking-ultrasonography test; the orocecal transit time (OCTT) was measured by lactulose hydrogen breath test, and fasting blood was collected. Plasma levels of ghrelin, motilin and neuropeptide Y (NPY) were measured by enzyme-linked immunosorbent assay kits.
RESULTS: AMT slowed the OCTT (109.2 ± 29.68 min vs 96.61 ± 23.9 min, P = 0.004) but did not affect liquid gastric emptying and had no effect on proximal gastric accommodation. AMT resulted in decreases in the visual analogue scale (VAS) for difficulty in drinking 600 and 800 mL of water (3.57 ± 0.94 vs 2.98 ± 0.85, 5.57 ± 0.82 vs 4.57 ± 0.98, P < 0.01 for both), although it had no significant effect on the VAS for difficulty in drinking 200 mL and 400 mL of water. AMT significantly increased the plasma ghrelin level (442.87 ± 176.79 pg/mL vs 526.87 ± 158.44 pg/mL, P = 0.04) and the neuropeptide-Y level (890.15 ± 131.46 pg/mL vs 965.64 ± 165.63 pg/mL, P = 0.03), whereas it had no effect on the MTL level.
CONCLUSION: Low-dose AMT could slow OCTT, make the stomach less sensitive and increase the plasma levels of ghrelin and NPY. Thus, we recommend the use of low-dose AMT for functional gastrointestinal disorders.
Core tip: Low-dose amitriptyline has been used to treat functional gastrointestinal disorders for many years, but the precise mechanism is still not clear. Brain-gut peptides, such as motilin, ghrelin and neuropeptide Y, may regulate gastrointestinal functions. However, evidence indicating the possible effects of amitriptyline on the levels of brain-gut peptides in healthy Chinese volunteers is limited. In this study, we conclude that low-dose amitriptyline can slow orocecal transit time, make the stomach less sensitive and increase the plasma levels of ghrelin and neuropeptide Y. Thus, we recommend the use of low-dose amitriptyline for functional gastrointestinal disorders.