title: Antinociceptive effect of shakuyakukanzoto, a Kampo medicine, in diabetic mice.
abstract: In this study, the antinociceptive effect of shakuyakukanzoto was investigated using streptozotocin-induced diabetic mice to certify its analgesic effect on diabetic patients. Shakuyakukanzoto (0.5 and 1.0 g/kg, p.o.) significantly increased the nociceptive threshold in diabetic mice. The antinociceptive activity of shakuyakukanzoto in diabetic mice was not antagonized by beta-funaltrexamine, naltrindole, or nor-binaltorphimine. The increased antinociceptive activity of (1.0 g/kg, p.o.) in diabetic mice was abolished by yohimbine (15 microg, i.t.), but not by NAN-190 (1 microg, i.t.), methysergide (15 microg, i.t.), or MDL-72222 (15 microg, i.t.). In shakuyakukanzoto diabetic mice treated with 6-hydroxydopamine (20 microg, i.t.) chemically lesioned noradrenergic pathways, shakuyakukanzoto (1.0 g/kg, p.o.) failed to exhibit an antinociceptive effect. Furthermore, the antinociceptive activity induced by norepinephrine (0.06 - 2 microg, i.t.) was markedly more potent in diabetic mice than in non-diabetic mice at the same dose. These results suggest that the antinociceptive effect of shakuyakukanzoto in diabetic mice is not mediated by the opioid systems and that this effect appears via selective activation of the spinal descending inhibitory alpha2-adrenergic systems without activating the serotonergic systems. The spinal alpha2-adrenoceptor-mediated analgesic mechanism was enhanced in diabetic mice, suggesting that shakuyakukanzoto exhibits its effect by activating the descending noradrenergic neurons.
authors.affiliation: Central Research Laboratories, Tsumura & Co, Japan. oomiya_yuuji@mail.tsumura.co.jp
authors.forename: Yuji
authors.initials: Y
authors.lastname: Omiya
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Mitsutoshi
authors.initials: M
authors.lastname: Yuzurihara
authors.forename: Mikio
authors.initials: M
authors.lastname: Murata
authors.forename: Masaki
authors.initials: M
authors.lastname: Aburada
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Kase
authors.forename: Shuichi
authors.initials: S
authors.lastname: Takeda
mesh_terms: D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology; D000700:Analgesics; D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000523:psychology*; D004305:Dose-Response Relationship, Drug; D004338:Drug Combinations; D004365:Drugs, Chinese Herbal / Q000494:pharmacology*; D006035:Glycyrrhiza; D008297:Male; D020835:Medicine, Kampo; D008784:Methysergide / Q000494:pharmacology; D051379:Mice; D009271:Naltrexone / Q000031:analogs & derivatives / Q000494:pharmacology; D009292:Narcotic Antagonists / Q000494:pharmacology; D016627:Oxidopamine / Q000494:pharmacology; D029596:Paeonia; D010147:Pain Measurement / Q000187:drug effects; D017288:Pain Threshold / Q000187:drug effects; D010879:Piperazines / Q000494:pharmacology; D012702:Serotonin Antagonists / Q000494:pharmacology; D013565:Sympatholytics / Q000494:pharmacology; D014326:Tropanes / Q000494:pharmacology; D015016:Yohimbine / Q000494:pharmacology
chemical_list: D000317:Adrenergic alpha-Antagonists; D000700:Analgesics; D004338:Drug Combinations; D004365:Drugs, Chinese Herbal; D009292:Narcotic Antagonists; D010879:Piperazines; D012702:Serotonin Antagonists; D013565:Sympatholytics; D014326:Tropanes; C038462:shakuyaku-kanzoh-toh; C058895:1-(2-methoxyphenyl)-4-(4-(2-phthalimido)butyl)piperazine; D015016:Yohimbine; C051844:norbinaltorphimine; D009271:Naltrexone; C024524:beta-funaltrexamine; D016627:Oxidopamine; C055382:naltrindole; C042253:bemesetron; D008784:Methysergide