ABSTRACT
<p><b>OBJECTIVE</b>To investigate the changes of large conductance Ca(2+)-activated K(+) channel (BK channel) on coronary smooth muscle cells from diabetic rats.</p><p><b>METHODS</b>Streptozotocin-induced rat diabetic animal model was used. Coronary smooth muscle cells were isolated by enzyme digestion. BK currents in control and diabetic groups were recorded by patch clamp technique in whole cell configuration, and BK channel protein expression was detected by Western blot. Calcium concentration was measured by fluorescence assay.</p><p><b>RESULTS</b>Compared with control group, BK current densities in diabetic group were significantly decreased when test potentials > 100 mV (P < 0.05). BK current densities were (275 ± 40) pA/pF in control group (n = 8) and (70 ± 10) pA/pF in diabetic group (n = 6) at 150 mV test potentials. α-subunit protein expression was similar between the groups (P > 0.05), however, β1-subunit protein expression was significantly reduced in diabetic group than in control group (P < 0.05). Calcium concentrations were significantly increased in diabetic group control group (151 ± 18) nmol/L (n = 6) than in control group (92 ± 7) nmol/L (n = 5, P < 0.05).</p><p><b>CONCLUSION</b>Observed β1-subunit downregulation, BK current density decrease and cytosolic calcium concentration increase in smooth muscle cells of diabetic coronary arteries may be associated with coronary dysfunction in diabetic rats.</p>
Subject(s)
Animals , Male , Rats , Calcium , Metabolism , Coronary Vessels , Metabolism , Diabetes Mellitus, Experimental , Metabolism , Large-Conductance Calcium-Activated Potassium Channels , Metabolism , Muscle, Smooth, Vascular , Metabolism , Patch-Clamp Techniques , Rats, Sprague-DawleyABSTRACT
OBJECTIVE@#To investigate the pathological change of mice organ intoxicated by Alangium Chinese and its poisoning mechanism.@*METHODS@#Mice were intoxicated by gavage with extract of Alangium Chinese. Then the histopathologic examination was made for evaluating the pathological changes in the organs of the poisoned mice by HE staining.@*RESULTS@#The main pathological changes included alveolar hemorrhage, pulmonary interstitial hemorrhage, sinus hepaticus expansion and congestion, hepatocyte edema, subarachnoid hemorrhage, congestion and hemorrhage of other organs.@*CONCLUSION@#The main target organs or tissue of Alangium Chinese are the lungs, liver and vascular smooth muscle. There is correlation between the toxic effect and the dosage.