Rho-kinase inhibitor, Y-27632, has an antinociceptive effect in mice

• Published in: European journal of pharmacology 2006-07, Vol.541 (1), p.49-52
• Main Authors: Büyükafşar, Kansu, Yalçın, İpek, Kurt, A. Hakan, Tiftik, R. Nalan, Şahan-Fırat, Seyhan, Aksu, Fazilet
• Format: Article
• Language: English
• Subjects: Amides - pharmacology; Analgesia; Analgesics - pharmacology; Animals; Behavior, Animal - drug effects; Biological and medical sciences; Blotting, Western; Brain - drug effects; Brain - enzymology; Dose-Response Relationship, Drug; Enzyme Inhibitors - pharmacology; Hot-plate; Inflammation; Intracellular Signaling Peptides and Proteins - antagonists & inhibitors; Intracellular Signaling Peptides and Proteins - metabolism; Male; Medical sciences; Mice; Mice, Inbred BALB C; Nociception; Pain - metabolism; Pain - physiopathology; Pain - prevention & control; Pain Measurement - methods; Pharmacology. Drug treatments; Protein-Serine-Threonine Kinases - antagonists & inhibitors; Protein-Serine-Threonine Kinases - metabolism; Pyridines - pharmacology; rho-Associated Kinases; Rho-kinase; Spinal Cord - drug effects; Spinal Cord - enzymology; Writhing; Y-27632
• ISSN: 0014-2999; 1879-0712
• DOI: 10.1016/j.ejphar.2006.04.042

The possible antinociceptive effect of a Rho-kinase inhibitor, (+)-( R)- trans-4-(1-aminoethyl)- N-(4-pyridyl) cyclohexanecarboxamide dihydrochloride monohydrate (Y-27632), was investigated in mice by using the hot-plate and abdominal constriction response (writhing) tests. In addition, the expression of Rho-kinase protein (ROCK-2) was studied in the mouse brain and spinal cord by Western blotting. Male balb/ c mice ( n = 8, for each group) were used in the experiment. Hot-plate latency and the number of writhes were recorded in control and in Y-27632-treated (1–5 mg/kg, i.p.) groups. Y-27632 (1 mg/kg) did not affect hot-plate latency; however, it considerably diminished the number of writhes, from 89 ± 12 in control to 30 ± 6 in the mice treated with 1 mg/kg Y-27632 ( P = 0.001). At a higher dose (5 mg/kg), Y-27632 prolonged the hot-plate latency from 8.7 ± 1.0 s to 14.4 ± 1.7 s ( P = 0.005) and decreased the number of writhes from 80 ± 8 to 24 ± 7 ( P = 0.002). Western blot analysis revealed that mouse spinal cord and brain homogenates expressed ROCK-2 protein. These results indicate that Rho-kinase may be involved in nociception and that its inhibitors, such as Y-27632, may represent a new type of antinociceptive drug.