치수에서 Eugenol이 iCGRP(immunoreactive calcitonin gene-related peptide)의 분비 조절에 미치는 영향

EFFECT OF EUGENOL ON REGULATION OF iCGRP RELEASE FROM THE BOVINE DENTAL PULP

Eugenol has been reported to reduce odontogenic pain and is known to have a structure similar to capsaicin, a potent stimulant of certain nociceptors. We have hypothesized that the analgesic effect of eugenol may be due, in part, to inhibition of capsaicin-sensitive nociceptors. To test this hypothesis, we evaluate whether eugenol inhibits capsaicin-sensitive release of immunoreactive calcitonin generated peptide(iCGRP) from bovine dental pulp. Freshly extracted bovine incisors were transported to the lab. on ice, Spilitted and pulp tissue was removed. The tissue was chopped into 200${\mu}m$ slices. Dental pulp was superfused(340 ${\mu}l/min$) in vitro with oxygenated Kreb's buffer. Eugenol and vehicle(0.02% 2-hydroxyl-${\beta}$-cyclodextrin) were administered prior to stimulation of pulp with capsaicin and iCGRP was measured by RIA. The results were as follows: 1. Administration of eugenol has no effect on basal release of iCGRP. 2. In the vehicle treated group, capsaicin evoked a 2.5-fold increase over basal iCGRP levels. 3. Administration of eugenol(600 ${\mu}M$) reduced capsaicin evoked release of iCGRP by more than 40%(153.4${\pm}$41.1% vs 258.9${\pm}$21.7%). 4. 2-hydroxylpropyl-${\beta}$-cyclodextrin of less than 0.02% is found to be an effective vehicle to dissolve eugenol without evoking iCGRP release from dental bovine pulp. These data indicate that eugenol inhibits pulpal capsaicin-sensitive fibers and suggest that intracanal medicament of eugenol may relieve pain, in part, by this mechanism.