ABSTRACT
Objective To observe the effect of intrathecal agmatine(AG) at the spinal cord level on morphine tolerance. Methods (1) Twenty-four SD rats were divided into four groups: control group, pure intrathecal injection(i.t.) of saline(15 μL); morphine group, i.t. morphine(15 μg/15 μL); AG group, i.t. AG (12.5 μg/15 μL); and morphine+AG group, i.t. morphine (15 μg/5 μg) and AG (12.5 μg/10 μL). Rats of the four groups were injected with 0.2 mg bee venom subcutaneously in the plantar 5 min after i.t, and the numbers of spontaneous paw withdrawal reflex were recorded within 1 hour. (2) Twenty-four SD rats were divided into three groups: control group, pure intrathecal saline(15 μL); morphine tolerance group, i.t. morphine(15 μg/5 μL) twice a day for 4 consecutive days; and morphine tolerance+AG group, i.t. morphine(15 μg/5 μL)twice a day for 4 consecutive days, on the fourth day the rats also received AG(12.5 μg/10 μL). Half of the rats were examined for thermal paw withdrawal latency and mechanical withdrawal threshold after i.t, and the other half was injected with 0.2 mg bee venom subcutaneously in the plantar 10 min after last dose; the number of spontaneous paw withdrawal reflex were recorded within 1 hour. Results (1)Compared with the control group, the numbers of flinches of intrathecal morphine and AG groups were significantly reduced(P<0.05). (2) In intrathecal morphine tolerance model, the thermal paw withdrawal latency and mechanical withdrawal threshold were significantly increased in the morphine tolerance+AG group compared with the control group (P<0.05);morphine tolerance + AG group had significantly stronger inhibitory effect against spontaneous s.c. BV-induced pain, with the number of spontaneous flinches within 1 hour decreased significantly in the morphine tolerance + AG group(P<0.05). Conclusion Intrathecal AG has synergistic effect with morphine in pain relieving, and it can also reverse the morphine tolerance induced by repeated i.t. injection.
ABSTRACT
<p><b>OBJECTIVE</b>To observe the effect of compound of gardenia oil and jujube seed oil learning and memory in ovariectomized rats and its mechanism.</p><p><b>METHODS</b>Animals were randomly divided into six groups: sham group, model group, estrogen group, low dose group, middle dose group and high dose group. The ovariectomized rat models were established by resection of the lateral ovaries. The effect of compound of gardenia oil and jujube seed oil on learning and memory in ovariectomized rats was observed by means of Morris water maze. Acetylcholinesterase (AchE) and nitric oxide synthase (NOS) activities in rat brain were determined.</p><p><b>RESULTS</b>The compound of gardenia oil and jujube seed oil could shorten the incubation period of appearance in castration rats and increase the number passing through Yuan Ping table in ovariectomized rats. As the training time extended, the incubation period of appearance was gradually shortened. The compound of gardenia oil and jujube seed oil could increase NOS activity, and decrease AChE activity in brain of ovariectomized rats.</p><p><b>CONCLUSION</b>The compound of jujube seed oil and gardenia oil could promote the learning and memory in ovariectomized rats. This effect may be related with the increase in activities of NOS, AchE in rat brain.</p>