Sensitization to psychostimulant drugs, as well as morphine, subjected to cross-sensitization with stress. The development of morphine sensitization is associated with enhancements in dopamine overflow in the Nucleus accumbens (NAc). This study aimed to examine the role of accumbal D1/D2-like dopamine receptors in restraint stress (RS) induced sensitization to morphine antinociceptive effects. Adult male Wistar rats weighing 220–250 g underwent stereotaxic surgery. Two stainless steel guide cannulae were bilaterally implanted, 1 mm above the NAc injection site. Different solutions of SCH-23390, as a D1-like receptor antagonist or sulpiride, as a D2-like receptor antagonist, were microinjected into the NAc five min before exposure to RS. Restraint stress lasted for 3 h, 10 min after RS termination; animals received a subcutaneous injection of morphine (1 mg/kg) for 3 consecutive days. The procedure was followed by a 5-day drug and/or stress-free period. After that, on the 9th day, the nociceptive response was evaluated by the tail-flick test. The results revealed that intra-NAc administration of D1/D2-like dopamine receptor antagonists, SCH-23390 or sulpiride, respectively, blocked morphine sensitization-induced by RS and morphine co-administration in rats for three consecutive days. This work provides new insight into the determinant role of accumbal dopamine receptors in morphine sensitization produced by RS-morphine co-administration.
相似文献In this research work, a systematic design of a novel anti-reflective layer using embedded plasmonic nanoparticles is investigated for a thin-film GaAs solar cell. First, an anti-reflective layer that is made from ITO or SiO2 is assumed in which Al nanoparticles are embedded inside them to manipulate the absorption and hence the photocurrent of a 500-nm GaAs solar cell. It is investigated that the Al nanoparticles embedded inside the anti-reflective coating improve the photocurrent of a GaAs solar cell. For instance, the 15.37 mA photocurrent is obtained for 500-nm bare GaAs cell, and it reached to 17.25 mA/cm2 and 20.18 mA/cm2 when an ITO anti-reflection is used with Al nanoparticles on top and inside that, respectively. It increases to 21.94 mA/cm2 and 24.98 mA/cm2 in the case of the anti-reflective layer made from SiO2 and Al nanoparticles at the top side or inside that, respectively. Finally, using a double anti-reflective layer that is made from SiO2-TiO2, the maximum photocurrents of 23.79 mA/cm2 and 24.68 mA /cm2 are obtained when Al nanoparticles are at the top side or inside that, respectively. The simulation results show that the embedding Al nanoparticles in the anti-reflective layer can improve the photocurrent of a thin-film GaAs solar cell.
相似文献Glioblastoma multiform (GBM) is known as an aggressive glial neoplasm. Recently incorporation of mesenchymal stem cells with anti-tumor drugs have been used due to lack of immunological responses and their easy accessibility. In this study, we have investigated the anti-proliferative and apoptotic activity of atorvastatin (Ator) in combination of mesenchymal stem cells (MSCs) on GBM cells in vitro and in vivo. The MSCs isolated from rats and characterized for their multi-potency features. The anti-proliferative and migration inhibition of Ator and MSCs were evaluated by MTT and scratch migration assays. The annexin/PI percentage and cell cycle arrest of treated C6 cells were evaluated until 72 h incubation. The animal model was established via injection of C6 cells in the brain of rats and subsequent injection of Ator each 3 days and single injection of MSCs until 12 days. The growth rate, migrational phenotype and cell cycle progression of C6 cells decreased and inhibited by the interplay of different factors in the presence of Ator and MSCs. The effect of Ator and MSCs on animal models displayed a significant reduction in tumor size and weight. Furthermore, histopathology evaluation proved low hypercellularity and mitosis index as well as mild invasive tumor cells for perivascular cuffing without pseudopalisading necrosis and small delicate vessels in Ator?+?MSCs condition. In summary, Ator and MSCs delivery to GBM model provides an effective strategy for targeted therapy of brain tumor.
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