ABSTRACT
Tinnitus can be described as the conscious perception of sound without external stimulation, and it is often accompanied by anxiety, depression, and insomnia. Current clinical treatments for tinnitus are ineffective. Although recent studies have indicated that the caudate-putamen nucleus may be a sensory gating area involved in noise elimination in tinnitus, the underlying mechanisms of this disorder are yet to be determined. To investigate the potential role of the caudate-putamen nucleus in experimentally induced tinnitus, we created a rat model of tinnitus induced by intraperitoneal administration of 350 mg/kg sodium salicylate. Our results revealed that the mean spontaneous firing rate of the caudate-putamen nucleus was increased by sodium salicylate treatment, while dopamine levels were decreased. In addition, electrical stimulation of the caudate-putamen nucleus markedly reduced the spontaneous firing rate of neurons in the primary auditory cortex. These findings suggest that the caudate-putamen nucleus plays a sensory gating role in sodium salicylate-induced tinnitus. This study was approved by the Institutional Animal Care and Use Committee of Peking University Health Science Center (approval No. A2010031) on December 6, 2017.
ABSTRACT
OBJECTIVE: To study the effect of Jianpi Liqi Recipe (JLR) on 5-fluorouracil (5-FU) relevant metabolic enzymes and CYP3A4 (the same enzyme of many chemotherapeutics) of mice with human gastric cancer transplanted tumor. METHODS: Totally 80 mice were randomly divided into the model group, the chemotherapy group, the JLR group, and the combination group (using chemotherapy combined JLR), 20 in each group. The human gastric cancer transplanted tumor mouse model was duplicated by hypodermic inoculating MKN-8 tumor cell suspension from the left armpit. Physiological saline or JLR was given to those in the model group or the JLR group at 0.25 mL each time, twice daily by gastrogavage from the 2nd day after transplantation. Mice in the chemotherapy group were given 0.25 mL physiological saline, twice daily by gastrogavage 2 days after transplantation, for 5 days in succession, and then they were peritoneal injected with 5-FU at the daily dose of 20 mg/kg, once daily for 5 days in succession from the 7th day of transplantation. Those in the combination were given 0.25 mL JLR, twice daily by gastrogavage, for 5 days in succession, and then they were peritoneal injected with 5-FU at the daily dose of 20 mg/kg, once daily for 5 days in succession from the 7th day of transplantation. The mRNA expressions of thymidine phosphorylase (TP), dihydropyrimidine dehydrogenase (DPD), and CYP3A4 were detected using RT-PCR. RESULTS: Compared with the model group and the chemotherapy group, mRNA expressions of TP and CYP3A4 obviously increased, mRNA expression of DPD obviously decreased in the JLR group and the combination group (P < 0.01). There was no statistical difference in mRNA expressions of TP, DPD, and CYP3A4 between the JLR group and the combination group (P > 0.05). CONCLUSION: JLR could promote the activation of 5-FU, suppress the decomposition and inactivation of 5-FU in the tumor tissue of mice, and improve the chemotherapeutic efficacy through up-regulating mRNA expressions of TP and CYP3A4, and suppressing the mRNA expression of DPD.
