Fig. 5.

Morphine-induced hypothermia and straub tail. A, acute morphine-induced hypothermia. Mice were injected with various doses of morphine subcutaneously, and test rectal temperatures were obtained 30 min later. Results are expressed as the change in body temperature (ΔTb). In the wild-type animals morphine dose-dependently induced hypothermia. However, there was no hypothermia found in the CD38 KO animals even at doses where maximal hypothermia was found in wild-type animals. Each bar represents five mice. B, acute effects of morphine on straub tail. Mice were injected with 10 mg/kg morphine subcutaneously, and straub tail was measured 30 min later. Each bar represents 6 to 10 mice. There was a significant reduction in straub tail in the CD38 KO mice compared with wild type (p < 0.05). Each bar represents five mice.