Enhanced pain reliving effect with a combination of TCV-309 and morphine in FBC mice.

<p>TCV-309, 3 and 10 μg/kg were injected i.v. at 10 days post tumor implantation and morphine 0.1 mg/kg and 0.3 mg/kg were injected s.c. 1 day after the injection of TCV-309 (A). Gabapentine 10 and 30 mg/kg i.v. were injected 11 days post tumor transplantation and morphine, 1 mg/kg was injected at 30 min after gabapentin injection (B). Morphine 0.3–30 mg/kg was injected at 11days post tumor transplantation (C). Pain-like behaviors were evaluated at 20 min after morphine injection. Various doses of TCV-309 were injected i.v. at 11 days post tumor implantation and morphine 0.3 mg/kg were injected s.c. 1 days after the injection of TCV-309 (D). One day after the injection of TCV-309, various doses of morphine were injected (E). Control mice received injections with a vehicle: saline. The pain-related behaviors that developed after tumor implantation in mice were not affected by vehicle treatments. Each group contained 11 mice. ^†P<0.05, *P<0.01 compared with the corresponding control (vehicle treated) values, as determined by analysis of variance followed by Tukey-Kramer test. ^§P<0.01 compared with the corresponding control (vehicle treated without morphine) values, as determined by analysis of variance followed by an unpaired Student's <i>t</i>-test.