Résumé
<p><b>OBJECTIVE</b>To investigate the correlation between uncoupling protein 2 (UCP2) expression and myocardial mitochondria injury in rats with sepsis induced by lipopolysaccharide (LPS).</p><p><b>METHODS</b>The rat model of sepsis was established through an intraperitoneal injection of LPS. Forty male Sprague-Dawley rats were randomly and equally divided into control group (an intraperitoneal injection of normal saline), sepsis 6 h group (LPS-6 h group), sepsis 12 h group (LPS-12 h group), sepsis 24 h group (LPS-24 h group), and sepsis 48 h group (LPS-48 h group). The serum and heart tissues were harvested at corresponding time points and myocardial mitochondria was extracted. The microplate reader was applied to measure creatine kinase (CK), creatine kinase-MB (CK-MB), and reactive oxygen species (ROS). Flow cytometry was applied to measure the degree of mitochondrial swelling and mitochondrial membrane potential (MMP). Western blot was used to measure the expression level of UCP2. Electron microscopy was applied to observe the morphological changes in heart tissues and myocardial mitochondria.</p><p><b>RESULTS</b>Compared with the control group, the LPS groups had significantly increased serum levels of CK, CK-MB, and myocardial ROS, as well as a significantly increased degree of mitochondrial swelling (P<0.05), and these values reached their peaks at 24 hours after LPS injection. The LPS groups had a significant decrease in MMP (P<0.05), which reached the lowest level at 24 hours after LPS injection. Western blot showed that the LPS groups had a significant increase in the expression level of myocardial UCP2 compared with the control group (P<0.05), which reached its peak at 24 hours after LPS injection. The results of electron microscopy showed mitochondrial swelling, partial rupture of the mitochondrial membrane, and cavity formation in rats in the LPS groups. The most severe lesions occurred in the LPS-24 h group. In rats with LPS, the ROS level in the myocardial mitochondria and the degree of mitochondrial swelling were positively correlated with the expression level of UCP2 (r=0.796 and 0.893, respectively; P<0.05), while MMP was negatively correlated with the expression level of UCP2 (r=-0.903, P<0.05).</p><p><b>CONCLUSIONS</b>In the rat model of sepsis, the myocardium and myocardial mitochondria have obvious injuries, and the expression level of UCP2 is closely correlated with mitochondrial injury. Therefore, UCP2 might play an important role in myocardial mitochondrial injury in sepsis.</p>
Sujets)
Animaux , Humains , Mâle , Rats , Cardiomyopathies , Génétique , Métabolisme , Modèles animaux de maladie humaine , Canaux ioniques , Génétique , Métabolisme , Lipopolysaccharides , Mitochondries du myocarde , Métabolisme , Protéines mitochondriales , Génétique , Métabolisme , Myocarde , Métabolisme , Rat Sprague-Dawley , Sepsie , Génétique , Métabolisme , Protéine-2 de découplageRésumé
<p><b>OBJECTIVE</b>To explore the relation between gap junction and meridian phenomenon.</p><p><b>METHODS</b>The oxygen partial pressure in acupoints [see text for formula] and in their corresponding non-acupoints of the Bladder Meridian was observed with the needle-type tissue oxygen tension sensor in the gap junction blocking goats by 1-Heptanol injection and the Connexin 43 (Cx43) gene knockout mice.</p><p><b>RESULTS</b>(1) The oxygen partial pressure in acupoints of Bladder Meridian on goats was higher than that in non-acupoints after 1-Heptanol injection with significant differences between them (both P < 0.01). (2) The oxygen partial pressure in acupoints of Bladder Meridian on goats increased significantly after injecting 1-Heptanol as compare with that either injecting normal saline or injecting nothing with significant differences between them (all P < 0.01). (3) The oxygen partial pressure in acupoints of the Bladder Meridian was significantly higher than that in the non-acupoint controls in Cx43 wild type (WT) mice (all P < 0.01). In Cx43 heterozygote (HT) mice, the oxygen partial pressure between acupoints and non-acupoint controls showed no significant differences (all P > 0.05). (4) In acupoints, the oxygen partial pressure in Cx43 WT mice was significantly higher than that in Cx43 HT mice (all P < 0.05), while in the corresponding non-acupoints, this difference had no statistically significant (all P > 0.05).</p><p><b>CONCLUSION</b>Gap junction maybe the essential factor in signal transduction of acupuncture.</p>
Sujets)
Animaux , Femelle , Mâle , Souris , Points d'acupuncture , Connexine 43 , Génétique , Métabolisme , Jonctions communicantes , Chimie , Génétique , Métabolisme , Capra , Méridiens , Souris knockout , Modèles animaux , Oxygène , Métabolisme , Pression partielle , Vessie urinaire , Chimie , MétabolismeRésumé
<p><b>OBJECTIVE</b>Nuclear factor-kappa B (NF-kappaB) is a critical transcription factor governing the expression of many cytokines that are involved in the pathogenesis of inflammatory diseases, such as asthma and rheumatoid arthritis. Melatonin (MT), a relatively safe and potent antioxidant which has shown efficacy in several chronic inflammatory models, may inhibit the expression of NF-kappaB and therefore might have a therapeutic use in asthma. This study aimed at observing the effect of MT on the expression of NF-kappaB and airway inflammation in a rat model of bronchial asthma.</p><p><b>METHODS</b>Twenty-four male Sprague-Dawley (SD) rats weighing 120 g to 170 g were randomly divided into three experimental groups (8 in each): (1) Asthmatic group: Rats were immunized on day 1 by intraperitoneal injection of 100 mg ovalbumin (OVA) in 1 ml of saline with 100 mg of alu minum hydroxide. From day 15 the animals were challenged with aerosolized OVA (1% in saline) for 20 minutes per day for 7 consecutive days. (2) MT group: OVA-sensitized rats were injected intraperitoneally with 10 mg/kg MT 30 minutes before each OVA challenge. (3) CONTROL GROUP: OVA for inhalation and MT for intraperitoneal injection was replaced with normal saline (NS). Airway responsiveness to aerosolized acetylcholine of 24 rats was detected six hours after the last challenge. Then the rats were lavaged and total and differentiated leukocytes counts in bronchoalveolar lavage fluid (BALF) were performed after staining with Wright-Giemsa staining. At the same time, levels of nitric oxide (NO) in BALF, inducible nitric oxide synthesis (iNOS) and constitute nitric oxide synthesis (cNOS) in the lung tissues were assessed with the use of nitrate reductase and chemical colorimetry, respectively. The expression of NF-kappaB in the lung tissues was observed by means of immunohistochemical staining.</p><p><b>RESULTS</b>(1) After OVA challenge, there was a significant decrease in airway responsiveness, lymphocytes and eosinophils in BALF in MT group compared with asthmatic group (P < 0.01 respectively); (2) There was a significant decrease in amounts of NO(2)(-)/NO(3)(-) in the BALF and levels of iNOS in the lung tissues in MT group comparing with asthmatic group (P < 0.01 respectively); and the levels of iNOS in the lung tissues was correlated positively with NO(2)(-)/NO(3)(-) in the BALF (P < 0.01), but there were no significant differences in activity of cNOS in any of the groups analyzed. (3) There was a significant increase in expression of NF-kappaB in lung tissues in asthmatic group compared with the other groups (P < 0.01), and so was in MT group compared with control group (P < 0.05).</p><p><b>CONCLUSIONS</b>MT could partially inhibit the expression of NF-kappaB and down-regulate the activity of iNOS in lung tissue, decrease the production of NO in BALF. These data suggest that the inhibitory effect of MT probably play a role in decreasing airway hyperresponsiveness and airway inflammation of asthmatic rats model.</p>
Sujets)
Animaux , Mâle , Rats , Antioxydants , Pharmacologie , Asthme , Traitement médicamenteux , Métabolisme , Liquide de lavage bronchoalvéolaire , Biologie cellulaire , Allergie et immunologie , Modèles animaux de maladie humaine , Poumon , Chimie , Anatomopathologie , Mélatonine , Pharmacologie , Facteur de transcription NF-kappa B , Monoxyde d'azote , Rat Sprague-DawleyRésumé
Objective To evaluated the effect of hyperbaric oxygenation therapy(HBO)on the RhoA ex- pression and nerve function after transient focal cerebral ischemia in a rat model of middle cerebral artery occlusion. Methods One hundred and twenty-six healthy Sprague-Dawley rats were used and randomly divided into a sham op- eration group(shame group,n=42),a treatment group(n=42),and a control group(n=42).The animal model of middle cerebral artery occlusion(MCAO)was established by using the Zea-Longa method with the animals in the treatment and the control groups,and sham operation was performed with those in the sham group.HBO was applied to the animals in the treatment group.The RhoA protein expression was observed by using immunohistochemistry technique,and the neurological function was evaluated by Bederson's scale at different time points after MCAO.Re- sults(1)Weakly positive expression of RhoA could be located in bilateral cortex and the basal ganglia in the sham group.The expression of RhoA in the treatment group and control group was increased as early as 6 hours after MCAO when compared with that of the sham group,and peaked at 48 h after MCAO and decreased after then,but was still higher than that of the shame group at 7th day to 14th day after MCAO.It was also found that the expression of RhoA of the treatment group was significantly lower than that of the control group(P
Résumé
<p><b>OBJECTIVE</b>To study the relationship between enhanced degree in the cancer lesion and angiogenesis in the tumor through early manifestations in enhanced helical CT in patients with bladder cancer.</p><p><b>METHODS</b>Fifty-three patients with bladder carcinoma were examined by pelvic plain CT and helical CT scan at peak enhancement of cancer lesion. Histologic grade, vascular endothelial growth factor (VEGF) and micro-vascular density (MVD) were analyzed for each resected cancer lesion. Pearson and Spearman correlation tests were used to assess the relationship between CT enhancement and histologic grade, VEGF or MVD.</p><p><b>RESULTS</b>In early enhancing phase of helical CT, different degrees of enhancement were observed in 73 bladder cancer lesions. The difference between average CT attenuation and MVD in different histologic grade cancer lesions was statistically significant (P < 0.001). A positive correlation was found between the CT enhancement and MVD (gamma = 0.936, P < 0.001), histologic grade (gamma = 0.75, P < 0.001), but VEGF of bladder cancer did not correlate with the CT enhancement or MVD.</p><p><b>CONCLUSION</b>The early enhancement of helical CT enhancement of bladder cancer, showing a positive relation to MVD and histologic grade, can reflect the tumor angiogenesis and blood supply.</p>