Nociception, capsaicin effect

Numerous neuropeptides are beheved to be involved with the transmission or inhibition of pain, and the hope is to utilize this approach as a strategy to induce analgesia. Substance P is reported to be a transmitter of nociceptive impulses (39), and therefore antagonists should be analgesic. Capsaicin [404-86-4], C2gH2yN02, is known to deplete substance P and cause analgesia (40), but its side effects are intolerable. Antagonists to bradykinin [58-82-2], a substance known to induce pain (41), have shown some success in preclinical trials. 

Activation of vanilloid receptors by capsaicin results in a release of several neuropeptides, among which is the neurokinin substance P. Substance P normally signals pain in nociceptive afferents, so capsaicin creates a false pain/burning sensation even though no actual tissue damage occurs. General Effects... 

INTRAPLANTAR INJECTION OF BERGAMOT ESSENTIAL OIL INTO THE MOUSE HINDPAW EFFECTS ON CAPSAICIN-INDUCED NOCICEPTIVE BEHAVIORS... 

Fig. 2. Antinociceptive effects of intraplantar BEO in the capsaicin test. BEO was injected into the plantar surface of the hindpaw 10 min prior to injection of capsaicin (50 ng/paw). Jojoba oil was used as a control, which was without affecting the capsaicin-induced nociceptive response. Data are means + S.E.M. in — 10 mice per group). p < 0.001, p < 0.01 when compared with Jojoba oil-treated controls by Dunnett s test.

Sakurada, T., Sakurada, S., Morrone, L. A., and Bagetta, G. (2008). Intraplantar injection of bergamot essential oil into the mouse hindpaw Effects on capsaicin-induced nociceptive behavior. In XI Workshop on Apoptosis in Biology and Medicine , Abstract book. 

Hayes, A.G., Skingle, M., and Tyers, M.B., Effects of single doses of capsaicin on nociceptive threshold in the mdesit. Neuropharmacology, 20, 505-511, 1981. 

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