Effects of 5-HT(3) antagonism on postprandial gastric volume and symptoms in humans.
BACKGROUND
Alosetron reduces symptoms of dyspepsia, but the physiological basis for the symptomatic benefit is unclear.


OBJECTIVE
To assess 5-HT3 antagonism on postprandial gastric volume and symptoms after ingestion of maximum tolerable volume of a liquid meal.


METHODS
In 36 healthy volunteers, we assessed effects of placebo, 0.5 and 1 mg b.d. alosetron on fasting and postprandial gastric volumes (using single photon emission computed tomography) and symptoms based on 100 mm VAS, 30 min after maximum volume ingested.


RESULTS
The 5-HT3 antagonist reduced postprandial symptoms (aggregate score: P < 0.05), nausea (P < 0.001), and tended to reduce bloating (P=0.08). Both 0.5 and 1 mg alosetron reduced nausea (P < 0.025); 1 mg alosetron reduced aggregate symptoms (P < 0.05) and bloating (P < 0.05). Effects on pain (P=0.19) and fullness (P=0.14) were not statistically significant. There were no significant effects of the 5-HT3 antagonist on volume of meal tolerated or on SPECT-measured fasting or postprandial gastric volumes.


CONCLUSIONS
5-HT3 antagonism reduces aggregate symptoms, nausea and bloating after a liquid meal without increase in gastric volumes, suggesting a role for 5-HT3 in afferent functions in healthy humans during the postprandial period.
Kuo
B
B
Enteric Neuroscience Program, Gastroenterology Research Unit, Mayo Clinic and Foundation, 200 First Street SW, Rochester, MN 55905, USA.
Camilleri
M
M
Burton
D
D
Viramontes
B
B
McKinzie
S
S
Thomforde
G
G
O'Connor
M K
MK
Brinkmann
B H
BH
D000328:Adult; D002243:Carbolines / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D019422:Dietary Sucrose / Q000008:administration & dosage* / Q000009:adverse effects; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D005215:Fasting; D005260:Female; D005526:Food, Formulated; D006801:Humans; D016014:Linear Models; D008297:Male; D009325:Nausea / Q000517:prevention & control*; D010147:Pain Measurement; D019518:Postprandial Period / Q000187:drug effects*; D012702:Serotonin Antagonists / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D013270:Stomach / Q000187:drug effects*; D015899:Tomography, Emission-Computed, Single-Photon
D002243:Carbolines; D019422:Dietary Sucrose; D012702:Serotonin Antagonists; C082131:Ensure formulated food; C090840:alosetron