Influence of Cortex mori on the Capsaicin-induced Neurogenic Inflammation

Yoon, Chang Yong; Shin, Dong Whan; Hong, Choong Man; Lee, Won Kyu; Jang, Dong Deuk; Chai, Ok Hee; Kang, Kyoung Jin; Lee, Moo Sam

Abstract

The root bark of mulberry (Morus alba L. Cortex Mori and other plant of the genus Morus) has been used as an antiphlogistic, diuretic, and expectorant in herbal medicine, and the crude drug is known as "Sangbaikpi" in Korea. Capsaicin, a neurotoxin extracted from a red peppers, has selective effects on peptide-containing C-fiber and induces the release of neuropeptides from sensory nerve ending. But, any reports about the influences of Cortex mori (CM) on the capsaicin-induced neurogenic inflammation were not found, and the precise mechanism of capsaicin-induced neurogenic inflammation remains incompletely understood. The purpose of this study was to determine whether CM could inhibit the capsaicin-induced cutaneous reaction, and to find out its action mechanism. For this purpose, influences of CM on the capsaicin-induced cutaneous reaction (vascular permeability) in back skin of Sprague-Dawley rat, capsaicin-induced histamine release, calcium influx and the change of intracellular cAMP level in rat peritoneal mast cell were estimated. Results obtained were as follows; 1. Pretreatment of CM inhibited remarkably the capsaicin-induced cutaneous reaction. 2. The capsaicin-induced histamine release was inhibited by pretreatment with CM. 3. Capsaicin-induced calcium influx into mast cell was also inhibited by pretreatment with CM. 4. Capsaicin-induced decrease of cAMP level in the mast cell was inhibited significantly by pretreatment with CM. These results suggest that CM contains some substances with an anti-neurogenic inflammatory activity which inhibit the capsaicin-induced cutaneous reaction through the mechanism of mast cell stabilization.