Résumé
<p><b>OBJECTIVE</b>To explore the impact of electroacupuncture (EA) on the protein expression of adenosine receptors in the heart of the rats with myocardial ischemia (MI).</p><p><b>METHODS</b>Thirty healthy male SD rats were divided randomly into a control group (=6), a model group (=12) and an EA group (=12). We ligated the left anterior descending artery (LAD) for MI model in the model group and EA group, and exposed the heart after opening the chest without ligation in the control group. EA, 2 Hz /15 Hz and 1.5-2 mA, was applied at bilateral"Neiguan"(PC 6) in the EA group for 20 min, once a day for continuous 5 days. No intervention except grabbing and fixation was used in the control group and model group. We applied 2% TTC staining to observe the infarct size of myocardium, colorimetry to analyze serum lactic dehydrogenase (LDH), creatine kinase (CK), creatine kinase isoenzyme (CK-MB), radio-immunity assessment to detect cardiac troponin T (cTnT), Western blot to evaluate the adenosine A1 receptor (A1AR), A2aAR, A2bAR and A3AR.</p><p><b>RESULTS</b>After treatment, myocardial infarction of (27.56±3.24)% was obvious in the model group; the myocardial infarction in the EA group was (21.04±3.61)%, with statistical significance (<0.05). The expressions of serum LDH, CK, CK-MB and cTnT levels in the model group increased compared with those in the control group (all<0.01), and the expressions of LDH, CK, CK-MB and cTnT levels in the EA group decreased compared with those in the model group (<0.05,<0.01). The A1AR expression in the model group was not different from that in the control group (>0.05), and A2aAR、A2bAR、A3AR expressions decreased (<0.05,<0.01). A2aAR and A2bAR expressions in the EA group increased compared with those in the model group (both<0.01), and there was no statistical significance between A1AR and A3AR expressions (both>0.05). .</p><p><b>CONCLUSION</b>EA may achieve cardioprotective effect by regulating the expressions of A2aAR and A2bAR in myocardial tissue, which induce the corresponding signal cascade for reducing myocardial infarction area.</p>
Résumé
OBJECTIVE@#To explore the impact of electroacupuncture (EA) on the AMPKα-HDAC5-HIF-1α signaling in the heart of the rats with myocardial ischemia (MI) via detecting the expressions of AMP-activated protein kinase α (AMPKα), histone deacetylase 5 (HDAC5), hypoxia inducible factor (HIF-1α) and vascular endothelial growth factor (VEGF).@*METHODS@#Thirty-six healthy male SD rats were randomized into a sham operation group (6 rats), a sham + EA group (6 rats), a model group (12 rats) and an EA group (12 rats). We ligated the left anterior descending artery (LAD) for MI model, and exposed the heart of rats after opening the chest without ligation for the rats in the sham operation gorup and the sham + EA group. On the 2nd day after LAD ligation, EA was applied at "Neiguan" (PC 6) with 2 Hz/15 Hz and 1.5-2 mA for 30 min in the EA group and sham+EA group, once a day for 4 days. The same fixation was used in the sham operation group and the model group, without EA. Myocardial infarction area was observed by TTC staining and serum cardiac troponin T (cTnT) was detected by radioimmunoassay. The expression of VEGF mRNA was detected by real time PCR. The protein expressions of AMPKα, HDAC5, HIF-1α and VEGF were detected by western blot.@*RESULTS@#Compared with the sham operation group, 4 days after LAD ligation, the myocardial infarction was obvious and the expression of serum cTnT increased in the model group (0.05). After EA for 4 days, the myocardial infarction area and cTnT expression decreased in the EA group (both <0.01); the VEGF mRNA and protein expressions and AMPKα, HDAC5, HIF-1α protein expressions increased (<0.05, <0.01).@*CONCLUSION@#EA could regulate the AMPKα-HDAC5-HIF-1α signaling in myocardial tissue, which may activate VEGF expression for angiogenesis signaling, reduce myocardial infarction area so as to achieve cardioprotective effect.
Sujets)
Animaux , Mâle , Rats , AMP-Activated Protein Kinases , Électroacupuncture , Histone deacetylases , Sous-unité alpha du facteur-1 induit par l'hypoxie , Ischémie myocardique , Rat Sprague-Dawley , Transduction du signal , Facteur de croissance endothéliale vasculaire de type ARésumé
Objective:To evaluate the occluding effect of 2 kinds of Er laser on dentinal tubules.Methods:27 dentine discs were prepared,etched with 0.5 mol/L EDTA and then divided into 3 groups(n =9).The samples in group A without treatment were used as the controls,in group B treated with Er:YAG laser irradiation and in group C treated with Er,Cr:YSGG laser irradiation.The occluding effect was examined by scanning electron microscopy (SEM).Results:Micrographs of SEMshowed obvious occluding effect in group B and C.The dentinal tubule exposure rates of group A,B and C were 33.61 0% ±7.545%,4.1 86% ±0.723% and 3.798% ± 0.843% respectively(among 3 groups,P 0.05).Conclusion:The 2 kinds of Er laser can block dentinal tu-bules.