Serotonin and experimental pain in healthy young volunteers.
OBJECTIVE
The role of serotonin in the modulation of nociceptive input has been widely studied, and a link between serum serotonin (S-5HT) and pain thresholds elicited in patients with chronic painful pathologies has been shown. In the light of contradictory concepts on pain message modulation by S-5HT, this study tries to define whether S-5HT displays a nociceptive or antinociceptive role in experimental pain evaluation in healthy volunteers.


METHODS
In 20 healthy young volunteers, 10 men and 10 women (21 +/- 2 years old), blood serotonin measurements were made, pressure pain thresholds was determined, and statistical analysis was performed.


RESULTS
This study showed a significant negative correlation of total blood serotonin with experimental pain detection threshold (P < 0.05, r = 0.444), but not with pain tolerance, while sex-related correlations of serotonin and thresholds were not significant. Lower serotonin concentration (P = 0.02), higher pain threshold (P < 0.01), and higher pain tolerance (P = 0.02) in men than in women were observed.


CONCLUSIONS
Low pain detection thresholds may be explained by a peripheral nociceptive effect of serotonin. Pain tolerance does not, however, encompass a similar pattern of serotoninergic involvement in pain control and may include other components that remain to be elucidated. These results call for further studies on a larger population.
Pickering
Gisèle
G
INSERM EMI 9904, Department of Clinical Pharmacology, University Hospital, Clermont-Ferrand, France. gisele.pickering@u-clermont.fr
Januel
Faïza
F
Dubray
Claude
C
Eschalier
Alain
A
D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D010146:Pain / Q000097:blood* / Q000175:diagnosis / Q000378:metabolism / Q000503:physiopathology*; D017288:Pain Threshold / Q000502:physiology*; D010812:Physical Stimulation / Q000379:methods; D012701:Serotonin / Q000097:blood* / Q000378:metabolism*; D013223:Statistics as Topic
D012701:Serotonin