Introduction: Ascorbic acid (AA) is present as a vitamin and neuromodulator in most part of the mammalian brain, especially in nucleus accumbens shell (Acbsh), which is one of the important areas controlling motor activity and anxiety. This study evaluates the effect of injection of AA and its co-administration with bromocriptin (Br) in Acbsh on motor activity and anxiety of rats by Open Field test.Methods: Forty nine adult male Wistar rats (220-270 g) were allocated into 7 groups: control (intact), sham AA (normal saline injected as AA vehicle), 3 groups of AA (12, 24 and 48 mg/rat/side), AA plus Br (AA 24 mg/rat/side and Br 25 mg/rat/side), sham AA plus Br. Drugs were injected (volume=1 mL) once, and duration of the test was 5 minutes.Results: Intra-accumbance injection of AA increased locomotor activity and decreased anxiety. Co-administration of AA and Br resulted in less motor activity and attenuation of Br-induced anxiety.Conclusion: Our results support the previous findings which introduced AA as an effective factor in regulation of locomotor activity and anxiety in Acbsh, that may be mediated by D2 receptors.

The distributions of axial static pressure coefficient and flow fluctuation in the test section which affect aerodynamic measurement in an open jet wind tunnel is presented. In this paper, the flow characteristics of the open jet automotive wind tunnel with passive reinjection and active reinjection were simultaneously investigated by experimental and numerical approaches. The axial static pressure coefficient variations can be reduced by passive or active reinjection, and recycle flow returns to the test section from the loophole is the main reason. The more mass flow rate improves the effect. Meanwhile, it is found that the improvement of the axial static pressure coefficient by reinjection is always better in the condition of 0° collector angle. The turbulence intensity in the collector angle of 15° is lower than that of 0° , and the reinjection increases the turbulence intensity near the collector. The increase of the turbulence intensity by active reinjection in the collector angle of 0° is greater than the collector angle of 15° for the 3. 28° diffusion angle. There are some peaks emerging at the frequencies of 40 Hz and 50 Hz, which indicates that the flow field fluctuations may have induced structural vibration. The peaks at several frequencies increase when the passive and active reinjection are conducted, and the increase of peak is correlate with the increase of the reinjection flow rate. Due to the reduction of average static pressure coefficient and increase of flow fluctuations, the application of passive and active reinjection should be considered at the same time.

We have previously shown that thymoquinone, the major active constituent of Nigella sativa L. seeds, exhibited anticonvulsant effect in pentylenetetrazole model. In the present study, in order to clarify the other actions of thymoquinone, on the CNS, we investigated its hypnotic and muscle relaxant effects using pentobarbital - induced hypnosis and the traction test, respectively. Also, we evaluated the effects of thymoquinone, on locomotors activity and motor coordination using the open - field activity and the rotarod tests respectively. The results showed that thymoquinone, did not show any hypnotic effect but exerted muscle relaxation in 30% of mice treated with the dose of 80 mg/Kg i.p. In rotarod test, thymoquinone, (40 and 80 mg/Kg. i.p.) produced motor incoordination dose denendently. In open - field test, we found that thymoquinone, with lower doses (1 and 2 mg/Kg, i.p.) could suppress locomotor activity and locomotor - associated behaviors. These findings indicate that thymoquinone, has not any hypnotic effect, but produces muscle relaxation, as well as motor incoordination, and reduces the locomotor activity.