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Objective: To investigate the relationship between the sensitization state of acupoints on the surface of the myocardial ischemia (MI) model mice and the changes in the electrophysiological properties of the dorsal root ganglion (DRG) neurons in the corresponding spinal cord segment, and its underlying mechanism., Methods: Sixty-eight male C57BL/6J mice were randomly divided into control and model groups (34 mice in each group). The model group received an intraperitoneal injection of 160 mg/kg isoproterenol (ISO) to establish the MI model, and the control group received an injection of the same dose of normal saline as the model group. After modeling for about 6 days, MI proportion was measured by HE staining to verify the pathological changes in the heart tissue. Evans blue (EB) dye was injected into the tail vein of mice to reflect the size, location, distribution, and number of exudates on the body surface. Then, whole-cell membrane currents, intrinsic excitability and membrane properties of different types of DRG neurons were evaluated by electrophysiological experiment in vitro ., Results: Compared with the control group, the heart size was larger, with pathological outcomes showing enlarged myocardial hypertrophy, destroyed structure of cardiomyocytes, with mononuclear cell infiltration among the cardiomyocytes in the model group. Compared with the control group, the number of EB exudation points was significantly increased ( P <0.01), which were mainly concentrated in the epidermis near the T1-T5 segment of the spinal cord, "Feishu" (BL13), "Jueyinshu" (BL14) and "Xinshu" (BL15) in the model group. Compared with the control group, the rheobase and action potential amplitude (APA) of DRG medium-sized neurons were obviously decreased ( P <0.01, P <0.05), while the whole-cell membrane currents, the spike numbers, the average instantaneous frequency, and the average discharge frequency were markedly increased ( P <0.01). There were no significant alterations in the membrane properties and intrinsic excitability induced by depolarized currents of small-sized neurons between groups. Compared with the control group, the whole-cell membrane currents, spike numbers, and the average instantaneous frequency were significantly increased in the model group( P <0.05, P <0.01) while rheobase was significantly decreased ( P <0.05) in DRG medium-sized neurons labeled with biotin and CGRP., Conclusion: After the mice were modeled by ISO, the DRG medium-size neurons in the T1-T5 segment of the spinal cord may mediate the sensitization of acupoints on the body surface through their different neuronal membrane properties and intrinsic excitabilities.

Objective: To investigate the relationship between acupoint sensitization on the body surface and neuronal intrinsic excitability of the medium- and small-size dorsal root ganglion (DRG) neurons from the perspective of ion channel kinetics in mice with gastric ulcer., Methods: Male C57BL/6J mice were randomly divided into control ( n =32) and model groups ( n =34). The gastric ulcer model was established by injection of 60% glacial acetic acid (0.2 mL/100 g) into the gastric wall muscle layer and submucosa near the pylorus in the minor curvature of the stomach. In contrast, the same dose of normal saline was injected in the same way in the control group. Six days after modeling, Evans blue (EB) solution was injected into the mouse's tail vein for observing the number and distribution of the exudation blue spots on the body surface. Histopathological changes of the gastric tissue were observed by H.E. staining. Then, whole-cell membrane currents and intrinsic excitability of medium- and small-size neurons in the spinal T9-T11 DRGs were measured by in vitro electrophysiology combining with biocytin-ABC method., Results: In the control group, EB exudation blue spots were not obvious, while in the model group, the blue spots on the body surface were densely distributed in the area of spinal T9-T11 segments, the epigastric region, and the skin around "Zhongwan" (CV12) and "Huaroumen" (ST24) regions, and near the surgical incision region. Compared with the control group, the model group had a high level of eosinophilic infiltrates in the submucosa of gastric tissues, severe gastric fossa structure damage, gastric fundus gland dilation and other pathological manifestations. The number of exudation blue spots was proportional to the degree of inflammatory reaction in the stomach. In comparison with the control group, the spike discharges of type II of medium-size DRG neurons in T9-T11 segments were decreased, and the current of whole-cell membrane was increased, basic intensity was decreased ( P <0.05), discharge frequency and discharge number were increased ( P <0.01, P <0.000 1); while the discharges of type I small-size DRG neurons were decreased, those of type II neurons increased, the whole-cell membrane current was decreased, and discharge frequency and discharge number were decreased ( P <0.01, P <0.000 1)., Conclusion: Both the medium- and small-size DRG neurons from the spinal T9-T11 segments involve in gastric ulcer-induced acupoint sensitization via their different spike discharge activities. And intrinsic excitability of these DRG neurons can not only dynamically encode the plasticity of acupoint sensitization, but also can help us understand the neural mechanism of acupoint sensitization induced by visceral injury.

Background & Objective: Liver metastasis is the most common cause of death due to colorectal cancer. Above 50% colorecal cancer patients have liver metastasis. This study was to investigate the effect of transfection of arresten gene on liver metastasis from human colorectal cancer (LoVo) xenografts in nude mice., Methods: The eukaryotic expression plasmid pSecTag2-arresten was transfected into human colorectal cancer cell line LoVo using Lipofectamine 2000. Cells were divided into pSecTag2-arresten group, pSecTag2 group and control group. Expressions of arresten at mRNA and protein levels were detected by RT-PCR and Western blot, respectively. The effect of arresten on proliferation of LoVo cells was measured using MTT assay. LoVo cells transfected with pSecTag2-arresten were implanted into nude mice to investigate the effect of arresten on hepatic metastasis of colorectal cancer. Microvessel density (MVD) of xenograft tumors was assessed using immunohistochemistry with FVIIIRag monoclonal antibody., Results: Arresten was successfully transfected and expressed in LoVo cells. Inhibition of cell proliferation did not differ significantly in all three groups (P > 0.05). The metastastic rate was lower in pSecTag2-arresten group [(25.1+/-2.1)%] than in pSecTag2 group [(87.1+/-1.2)% or control group [(87.1+/-1.5)%] in LoVo cells (P < 0.05). The number of xenograft tumors and MVD were higher in pSecTag2-arresten group [(4.5 +/-0.5) and (15.3+/-3.5)] than in pSecTag2 group [(19.6+/-2.5) and (42.2+/-2.6)] or in control group [(20.4+/-2.5)and (45.6+/-5.1)] in nude mice., Conclusion: Arresten can inhibit hepatic metastasis from colorectal cancer, which may be through its inhibition on tumor angiogenesis.

Objective: To explore the eukaryotic expression of arresten in CHO cells and to investigate its basic biological activities., Methods: CHO cells were divided into three groups: transfected pSecTag-arresten group, transfected pSecTag group and control group without transfection. PSecTag-arresten was transfected into CHO cells by Lipofectamine 2000 method. The arresten mRNA in CHO cells was assayed by RT-PCR. The protein expression of arresten gene was examined by Western-Blot. The cells expressing arresten were screened out by Zeocin. The effect of arresten on huvec cell migration and anchoring to three-dimensional vascular structures was measured., Results: The result of RT-PCR and Western-blot showed that arresten gene has been successfully transfected into CHO cells and expressed in those cells. Arrssten inhibited huvec cell migration and anchoring to three-dimensional vascular structures., Conclusion: CHO cells expressing arresten have been obtained successfully. Arresten can inhibit huvec cell migration and anchoring to three-dimensional vascular structures, indicating that it might be one of its anti-angiogenetic approaches.