A possible role for saliva as a diagnostic fluid in patients with chronic pain.
OBJECTIVE
The focus of this review was on proteins and peptides found in saliva. Of greatest interest were those neuropeptides relevant to nociception and to the pathogenesis of chronic pain syndromes. An additional goal was to develop a standardized protocol to collect saliva for laboratory assessment.


METHODS
Data were obtained through discussion with experts at the medical schools in San Antonio and Heidelberg and a Medline literature search involving all relevant studies from 1966 to 1997. The literature search was based on the following key terms: saliva, serotonin, neuropeptide, substance P (SP), calcitonin gene-related peptide (CGRP), and nerve growth factor (NGF).


RESULTS
The mean concentration of SP in the saliva of healthy normal controls ranged from 9.6 to 220 pg/mL. Generally, the concentration of SP was approximately three times higher in saliva than in plasma. In a number of painful conditions, particularly tension headache, substantial elevations of salivary SP were found. Mean values for salivary CGRP in healthy controls were approximately 22 pmol/L and were significantly elevated in patients with migraine attacks or cluster headache. There were no data to indicate prior quantitative determination of NGF in human saliva.


CONCLUSIONS
After sampling and processing techniques have been standardized, measurement of neuropeptides in human saliva could provide a valuable tool for study of patients with chronic painful disorders such as rheumatoid arthritis, osteoarthritis, and even fibromyalgia syndrome.
Fischer
H P
HP
Ruprecht-Karls-Universität Heidelberg, Medizinische Klinik und Poliklinik, Germany.
Eich
W
W
Russell
I J
IJ
D000818:Animals; D001172:Arthritis, Rheumatoid / Q000175:diagnosis / Q000378:metabolism; D002908:Chronic Disease; D005260:Female; D005356:Fibromyalgia / Q000175:diagnosis / Q000378:metabolism; D006801:Humans; D008297:Male; D009479:Neuropeptides / Q000378:metabolism; D010003:Osteoarthritis / Q000175:diagnosis / Q000378:metabolism; D010146:Pain / Q000175:diagnosis* / Q000378:metabolism; D012463:Saliva; D012471:Salivary Proteins and Peptides / Q000378:metabolism; D012701:Serotonin / Q000378:metabolism; D013048:Specimen Handling / Q000379:methods / Q000592:standards
D009479:Neuropeptides; D012471:Salivary Proteins and Peptides; D012701:Serotonin