Capsaicin antinociceptive activity

At present, BP 2.94 (36) is under clinical development in Phase II trials for the treatment of asthma, pneumoallergic diseases, and others. Preclinical studies in rodents clearly displayed anti-inflammatory as well as antinociceptive activity of BP 2.94 (36) given orally at low doses. These effects are mediated by inhibitory H3 receptors located on sensory C-fibres in several different tissues. In particular, capsaicin-induced plasma protein extravasation was dose-dependently inhibited in airways, digestive tract, skin, conjunctiva, urinaiy bladder, nasal mucosa, and dura mater of the rat. In the p-phenylbenzoquinone-induced writhing test in mice, BP 2.94 (36) had a pronounced antinociceptive activity similar to that of acetylsalicylic acid. This effect was significantly abolished by the H3 receptor antagonist thioperamide but not by naloxone. Furthermore, BP 2.94 (36) reduced zymosan-induced edema. This antiinflammatory effect was also abolished by thioperamide [6]. 

Kamei J, Saitoh A, Suzuki T, Misawa M, Nagase H, Kasuya Y (1995b) Buprenorphine exerts its antinociceptive activity via mu 1-opioid receptors. Life Sci 56 PL285-290 Kamei J, Morita K, Ohsawa M, Onodera K (1999) Effects of epinastine on the antitussive and rewarding effects of dihydrocodeine in mice. Methods Lind Exp Clin Pharmacol 21 663-668 Kamei J, Morita K, Saitoh A, Nagase H (2003) The antitussive effects of endomorphin-1 and endomorphin-2 in mice, Eur J Pharmacol 467 219-222 Kamei J, Yoshikawa Y, Saitoh A (2006) Effect of A-arachidonoyl-(2-methyl-4-hydroxyphenyl) amine (VDMll), an anandamide transporter inhibitor, on capsaicin-induced cough in mice. Cough 2 2... 

The antinociceptive activity of capsaicin administered intrathecally to the lumbar enlargement of the spinal cord through a catheter chronically implanted in the subarachnoid space was first investigated by Yaksh et al. (1979). They observed that most of the animals receiving this treatment were unresponsive to noxious thermal stimuli in the hot-plate and tail-... 

In addition to its effects on cell growth, CLP elicits antinociceptive and anti-inflammatory activities. Peripheral antinociceptive activity was investigated by acetic acid-induced writhing model. CLP (0.1-100 mcM/kg) inhibited acetic acid-induced abdominal constrictions dose dependently (1C50 = 0.0945). Central antinociceptive activity of CLP was demonstrated in the hot plate test. CLP (100 mcM/kg, p.o.) increased latency time 90, 120, and 150 min after treatment. Similarly, CLP caused an inhibition of nociception in formalin test. Anti-inflammatory activity of CLP was evaluated in capsaicin-induced ear edema and carrageenan-induced peripheral inflammation tests. Following oral administration at a dose of 100 mcM/kg, CLP inhibited capsaicin-induced ear edema by 55.8% and reduced leukocyte migration to the inflammatory sites by 48.3% [61]. 

Urban [20] described a capsaicin-analogue compound (SDZ 249-665), with antinociceptive and anti-hyperalgesic activity as well as reduced pungency. In addition, it does not cause bronchoconstriction or changes in blood pressure. 

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