title: Involvement of the Heme-Oxygenase Pathway in the Antiallodynic and Antihyperalgesic Activity of Harpagophytum procumbens in Rats.
abstract: Harpagophytum procumbens (H. procumbens), also known as Devil's Claw, has been used to treat a wide range of pathological conditions, including pain, arthritis and inflammation. Inflammatory mediators, released at the site of injury, can sensitize nociceptive terminals and are responsible for allodynia and hyperalgesia. Carbon monoxide (CO), produced in a reaction catalyzed by the enzyme heme oxygenase (HO), may play a role in nociceptive processing and has also been recognized to act as a neurotransmitter or neuromodulator in the nervous system. This study was designed to investigate whether the HO/CO pathway is involved in the analgesic response of H. procumbens in carrageenan-induced hyperalgesia in rats. Mechanical allodynia and thermal hyperalgesia were evaluated by using von Frey filaments and the plantar test, respectively. The results of our experiments showed that pretreatment with the HO inhibitor ZnPP IX significantly decreased the antihyperalgesic effect produced by H. procumbens (800 mg/kg, i.p.) in carrageenan-injected rats. Consistently, the pretreatment with hemin, a HO-1 substrate, or CORM-3, a CO releasing molecule, before a low dose of H. procumbens (300 mg/kg, i.p.) induced a clear antiallodynic response in carrageenan injected rats. These results suggest the involvement of HO-1/CO system in the antiallodynic and antihyperalgesic effect of H. procumbens in carrageenan-induced inflammatory pain.
authors.affiliation: Department of Drug Sciences, Pharmacology and Toxicology Section, University of Catania, Viale A. Doria 6, Catania 95125, Italy. cparenti@unict.it.
authors.forename: Carmela
authors.initials: C
authors.lastname: Parenti
authors.affiliation: Department of Drug Sciences, Medicinal Chemistry Section, University of Catania, Viale A. Doria 6, Catania 95125, Italy. garico@unict.it.
authors.forename: Giuseppina
authors.initials: G
authors.lastname: Aricò
authors.affiliation: Department of Drug Sciences, Pharmacology and Toxicology Section, University of Catania, Viale A. Doria 6, Catania 95125, Italy. chiechio@unict.it.
authors.forename: Santina
authors.initials: S
authors.lastname: Chiechio
authors.affiliation: Department of Biomedical and Biotechnological Sciences, Pharmacology Section, University of Catania, Viale A. Doria 6, Catania 95125, Italy. giuliadibenedetto@libero.it.
authors.forename: Giulia
authors.initials: G
authors.lastname: Di Benedetto
authors.affiliation: Department of Biomedical and Biotechnological Sciences, Phisiology Section, University of Catania, Viale A. Doria 6, Catania 95125, Italy. parenti@unict.it.
authors.forename: Rosalba
authors.initials: R
authors.lastname: Parenti
authors.affiliation: Department of Drug Sciences, Pharmacology and Toxicology Section, University of Catania, Viale A. Doria 6, Catania 95125, Italy. scotog@unict.it.
authors.forename: Giovanna M
authors.initials: GM
authors.lastname: Scoto
mesh_terms: D000700:Analgesics / Q000494:pharmacology*; D000818:Animals; D002248:Carbon Monoxide / Q000378:metabolism; D002351:Carrageenan / Q000633:toxicity; D031684:Harpagophytum / Q000737:chemistry*; D006419:Heme Oxygenase (Decyclizing) / Q000037:antagonists & inhibitors*; D006930:Hyperalgesia / Q000139:chemically induced / Q000188:drug therapy*; D007249:Inflammation / Q000139:chemically induced / Q000188:drug therapy*; D008297:Male; D010146:Pain / Q000188:drug therapy*; D010936:Plant Extracts / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D000700:Analgesics; D010936:Plant Extracts; D002248:Carbon Monoxide; D002351:Carrageenan; D006419:Heme Oxygenase (Decyclizing)
keywords: Harpagophytum procumbens; allodynia; carbon monoxide; carrageenan; hyperalgesia; rat