Sakurada T, Yogo H, Katsumata K, Tan-No K, Sakurada S, Kisara K, Ohba M
Department of Pharmacology, Tohoku College of Pharmacy, Sendai, Japan.
Brain Res. 1994 Jun 27;649(1-2):319-22. doi: 10.1016/0006-8993(94)91080-4.
The peptide NK1-receptor antagonists, sendide and [D-Trp7]sendide, have been evaluated for antinociceptive activity in the capsaicin test. Both peptides, injected intrathecally (i.t.) 5 min prior to intraplantar capsaicin, produced a dose-dependent reduction of the capsaicin-induced paw licking response. Naloxone (4.0 mg/kg) pretreatment did not affect sendide- and [D-Trp7]sendide-induced antinociception, whereas naloxone at a dose of 0.5 mg/kg antagonized the antinociceptive effect of i.t. administered morphine. Conversely, the antinociceptive action induced by both NK1-receptor antagonists was reduced significantly by i.t. co-administration of substance P. Morphine-induced antinociception was not antagonized by co-administration of substance P. These results led us to the understanding of differential action mechanism of NK1-receptor antagonist- and morphine-induced antinociception as assayed by the capsaicin test.
肽类NK1受体拮抗剂sendide和[D-Trp7]sendide已在辣椒素试验中评估其抗伤害感受活性。在足底注射辣椒素前5分钟鞘内注射（i.t.）这两种肽，均可使辣椒素诱导的舔足反应呈剂量依赖性降低。纳洛酮（4.0毫克/千克）预处理不影响sendide和[D-Trp7]sendide诱导的抗伤害感受，而剂量为0.5毫克/千克的纳洛酮可拮抗鞘内注射吗啡的抗伤害感受作用。相反，鞘内共同给予P物质可显著降低两种NK1受体拮抗剂诱导的抗伤害感受作用。共同给予P物质未拮抗吗啡诱导的抗伤害感受作用。这些结果使我们了解了通过辣椒素试验测定的NK1受体拮抗剂和吗啡诱导的抗伤害感受的不同作用机制。
