ABSTRACT
Atherosclerosis is a kind of complex progressive inflammation.Exposure to atherogenic risk factors,particularly OxLDL,induces the activity of BKCa in endothelial cell,monocyte/macrophage(M?),vascular smooth muscle cell,platelet and other cells to activate,which precipitates dysfunction of the cells and therefore contributes to the development of atherosclerosis.This article briefly reviews the reseach progress in BKCa participating in the development of atherosclerosis.
ABSTRACT
Objective To evaluate the changes of left ventricular regional function in normal subjects with aging and the influencing factors by Doppler tissue imaging. Methods One hundred and twelve normal subjects were divided into four groups according to age: I group with age≤18 years old ; II group with 18 60 years old. Using a quantitative tissue velocity analysis system and tissue tracking, the peak velocities of different ventricular segments at systole, early and late diastole (Vs, Ve,Va) , the Ve/Va ratios were obtained and the effects of age, gender, heart rate and STd were analyzed. Results (1) Peak velocities of different segments of each wall were decreased one by one from mitral annulus, the basal, middle segment to the apical portion. (2) Peak velocities of different ventricular walls were significantly different, with the antero- and posterio-inter-ventricular septum being the lowest CVe (6. 89?2. 60) ,(7. 94?2. 64)cm/s]and with the latero-,posterio-,antero, and inferior walls of the left ventricle being higherCVe (9. 85?3. 02) , (9. 80?3. 09), (8. 86?3. 16), (8. 23?2. 48) cm/s] . (3) Peak velocities of different segments were associated with age, STd, BMI, heart rate and not associated with gender. (4) The Ve/Va ratios were increased one by one from mitral annulus, basal, middle segment to apical portion, and were significantly lower in III group and IV group than in I group and II group. Conclusions Peak velocities of different segments at different walls change regularly and age is the most important influencing factor to the diastolic velocities.
ABSTRACT
Objective To study the effects of Nitric oxide(NO),Nitric oxide synthases (NOS)on calcium-activated potassium channels (KCa) of mesenteric artery smooth muscle(SMC)between patients with essential hypertension (EH) and normotensive patients.Methods (1)Mesenteric artery branch from 21 EH and 18 normotensive patients respectively was digested by enzyme.Patch clamp technique was used to pull cell-attached and inside-out patches on mesenteric artery SMC from EH.The signal channel open number probability (Po),open dwell-time(To) and close dwell- time(Tc),were recorded.(2)The levels of plasma NO?NOS were measured by colorimetry analysis method.(3)The analysis of linear correlation was performed to estimate the relationship between the levels of plasma NO and Po?To?Tc of KCa of mesenteric artery SMC in the subjects of the two groups.Results (1)Compared to that of normotensive patients,the activities of KCa channels of patients with EH was higher.After adding Ca 2+ to cytoplasm,the Po of KCa channels in normotensive patients increased significantly.But there were few changes in EH group.(2)The levels of plasma NO?NOS were lower in EH group than in control group.(3)Linear correlation analysis showed that the levels of plasma NO were correlated positively with Po?To in normotensive patients,wherese the positive correlation were decreased in EH group.Conclusion The activities of KCa channels of patients with EH increase significantly.but the sensitivity to Ca 2+ decreased.NO?NOS may stimulate the KCa channels of normotensive and EH patients,but they may not be main factors in EH patients.