The external elastic lamina (EEL) serves as a barrier for cells and macromolecules between the media and adventitia in the vascular wall. We evaluated the morphological changes and quantitative assessments of the EEL architecture in the coronary circulation of pigs fed with a high cholesterol diet. Confocal microscopy analysis of the EEL from hypercholesterolemic coronary arteries revealed an altered pattern characterized by fragmentation and disorganization of the EEL associated with an increase in the thickness. Computerized digital analysis of the images obtained by confocal scanning microscopy demonstrated that compared to normal coronary arteries, the EEL of hypercholesterolemic coronary arteries decreased in the percentage of their elastin content (30.80 +/- 1.64% vs. 47.85 +/- 1.82%, p = 0.001). The percentage of elastin content was negatively correlated with the vessel wall area (r = -0.82, p = 0.001). The immunoreactivity for matrix metalloproteinase-3 (MMP-3) increased in cholesterol-fed coronary arteries, predominantly in the neointima and adventitia. This study demonstrates that experimental hypercholesterolemia induced ultrastructural changes of the EEL in coronary circulation. The EEL may also be an atherosclerosis-prone area compared with the intima. The EEL may play an important role in the development of structural changes which characterizes the early phase of coronary atherosclerosis and vascular remodeling.
Animal ; Arteries/ultrastructure ; Arteries/enzymology ; Coronary Vessels/ultrastructure* ; Coronary Vessels/enzymology ; Elastic Tissue/ultrastructure* ; Elastic Tissue/enzymology ; Female ; Hypercholesterolemia/pathology* ; Hypercholesterolemia/enzymology ; Stromelysin 1/metabolism ; Swine

OBJECTIVETo observe the developing changes of adventitia in restenosis after precutaneous transluminal angioplasty(PTA), and investigate the effect of androgen on restenosis through contrasting the castrated male rat models and its mechanism.

METHODSModels were constructed of castrated male rats and restenosis of the common carotid artery, and specimens were collected at the 3rd, 7th, 14th and 28th day respectively after modeling. Hematoxylin and eosin staining, immunohistochemical staining, and electronic microscopy were performed to observe the condition of restenosis.

RESULTSProliferating cells occurred in adventitia first and phenotype of adventitial cells was changed at the 3rd day after PTA. The adventitial proliferating index was the highest at the 7th day after PTA, and proliferating migration towards intimal was observed. The proliferating cells mostly occurred in the middle layer and neointima at the 14th day after PTA. The areas of adventitia and neointima were larger and the degrees of restenosis were higher in the castrated rats than in the non-castrated ones at different time points. Take the 14 d group, the adventitial area was[(3,566 +/- 337) micron2 vs (2,751 +/- 401) micron2, P = 0.008], the neointimal area[(3,553 +/- 477) micron2 vs (2,757 +/- 435) micron2, P = 0.025], the restenosis rate[(76 +/- 2)% vs (60 +/- 8)%, P = 0.005], and the proliferating index [(29 +/- 2)% vs (13 +/- 1)%, P < 0.001].

CONCLUSIONAdventitial proliferation and migration contribute to restenosis after PTA; Androgen in rats can physiologically relieve restenosis, probably through intervening in the activation of adventitia.

Actins ; analysis ; Androgens ; physiology ; Angioplasty, Balloon, Coronary ; Animals ; Bromodeoxyuridine ; metabolism ; Coronary Restenosis ; etiology ; pathology ; Coronary Vessels ; pathology ; ultrastructure ; Immunohistochemistry ; Male ; Orchiectomy ; Rats ; Rats, Sprague-Dawley

BACKGROUNDCoronary microembolization (CME) has been frequently seen in acute coronary syndromes and percutaneous coronary intervention. Small animal models are required for further studies of CME related to severe prognosis. This study aimed to explore a new mouse model of CME.

METHODSThe mouse model of CME was established by injecting polystyrene microspheres into the left ventricular chamber during 15-s occlusion of the ascending aorta. Based on the average diameter and dosage used, 30 C57BL/6 male mice were randomly divided into five groups (n = 6 in each): 9 μm/500,000, 9 μm/800,000, 17 μm/200,000, 17 μm/500,000, and sham groups. The postoperative survival and performance of the mice were recorded. The mice were sacrificed 3 or 10 days after the surgery. The heart tissues were harvested for hematoxylin and eosin staining and Masson trichrome staining to compare the extent of inflammatory cellular infiltration and fibrin deposition among groups and for scanning transmission electron microscopic examinations to see the ultrastructural changes after CME.

RESULTSSurvival analysis demonstrated that the cumulative survival rate of the 17 μm/500,000 group was significantly lower than that of the sham group (0/6 vs. 6/6, P = 0.001). The cumulative survival rate of the 17 μm/200,000 group was lower than those of the sham and 9 μm groups with no statistical difference (cumulative survival rate of the 17 μm/200,000, 9 μm/800,000, 9 μm/500,000, and sham groups was 4/6, 5/6, 6/6, and 6/6, respectively). The pathological alterations were similar between the 9 μm/500,000 and 9 μm/800,000 groups. The extent of inflammatory cellular infiltration and fibrin deposition was more severe in the 17 μm/200,000 group than in the 9 μm/500,000 and 9 μm/800,000 groups 3 and 10 days after the surgery. Scanning transmission electron microscopic examinations revealed platelet aggregation and adhesion, microthrombi formation, and changes in cardiomyocytes.

CONCLUSIONThe injection of 500,000 polystyrene microspheres at an average diameter of 9 μm is proved to be appropriate for the mouse model of CME based on the general conditions, postoperative survival rates, and pathological changes.

Animals ; Brain ; pathology ; Coronary Occlusion ; pathology ; surgery ; Coronary Vessels ; pathology ; surgery ; ultrastructure ; Disease Models, Animal ; Embolization, Therapeutic ; Kidney ; pathology ; Male ; Mice ; Mice, Inbred C57BL ; Microscopy, Electron, Scanning Transmission ; Myocardium ; pathology ; Platelet Aggregation ; physiology

OBJECTIVETo assess the effect of beta blocker on blood flow velocity and reserve on the intramural coronary artery of patients with myocardial bridging.

METHODSIn 8 patients with myocardial bridge, intracoronary Doppler was performed before and after esmolol was given intravenously. The basic average peak velocity (bAPV), hyperaemic average peak velocity (hAPV) of blood flow, and coronary flow reserve (CFR) proximal and distal to the mural myocardial bridging was measured and compared.

RESULTSAfter esmolol injection, the mural coronary diameter systolic reduction decreased from (58.0 +/- 14.7)% to (26.0 +/- 9.8)% (P < 0.01); the bAPV proximal and distal to myocardial bridging separately decreased from (19.4 +/- 4.9) cm/s and (18.4 +/- 3.6) cm/s to (4.7 +/- 3.9) cm/s (P < 0.01) and (15.1 +/- 1.5) cm/s (P < 0.05). Under hyperemization, esmolol changed the hAPV of proximal and distal to myocardial bridging separately from (54.1 +/- 14.9) cm/s and (44.7 +/- 9.4) cm/s to (49.7 +/- 16.4) cm/s and (48.9 +/- 10.1) cm/s (all P > 0.05); thus, the value of CFR both proximal and distal to myocardial bridge increased separately from 2.8 +/- 0.3 and 2.5 +/- 0.5 to 3.4 +/- 0.5 and 3.2 +/- 0.6 (all P < 0.01).

CONCLUSIONEsmolol can decreased the compression of the intramural coronary artery and increased the CFR to normal level of it.

Adrenergic beta-Antagonists ; pharmacology ; therapeutic use ; Coronary Circulation ; drug effects ; physiology ; Coronary Vessels ; diagnostic imaging ; drug effects ; physiopathology ; Female ; Humans ; Male ; Middle Aged ; Myocardial Bridging ; drug therapy ; physiopathology ; ultrastructure ; Propanolamines ; pharmacology ; therapeutic use ; Ultrasonography, Interventional

OBJECTIVE: The differences in the thickness of fibrous cap and the percentage of fatty core of the coronary atherosclerotic plaques between sudden coronary death (SCD) group and the control group were investigated. METHODS: Sixty-four autopsy cases were divided into SCD and control groups. Samples were taken from the most severely damaged portions of the coronary atherosclerotic plaques, sectioned, stained with HE, and the percentage of examined by light microscopy for morphologic changes and structural alternations. Image analysis system was adopted to compare the thickness of fibrous cap and percentage of fatty core in the whole plaque between the two groups, and allthe data were analyzed and calculated with SPSS 11.5 statistic software. RESULTS: There were 15 grade III and 21 grade IV atherosclerotic cases found in the SCD group, while there were 16 and 12 found in the control group, respectively. Although no significant differences on the severity of atherosclerosis were found between the two groups (P > 0.05), there were significant differences on the thickness of the fibrous cap and the percentage of fatty core found between the two groups (P < 0.01). CONCLUSION Our study indicates that there are significant differences in the thickness of fibrous cap and the percentage of fatty core in atherosclerosis plaques between the SCD group and the control group. These observed differences may be helpful for morphological diagnosis of SCD.
Adult ; Aged ; Cadaver ; Coronary Artery Disease/pathology* ; Coronary Vessels/ultrastructure* ; Death, Sudden, Cardiac/pathology* ; Female ; Fibrosis ; Humans ; Male ; Middle Aged ; Myocardium/pathology* ; Rupture, Spontaneous/pathology* ; Severity of Illness Index ; Young Adult

OBJECTIVETo observe the effects of oral administration of guanxin II decoction (GX II) on cardiovascular function, especially on the dynamics of coronary blood flow in healthy males.

METHODSChanges of heart rate, diastolic pressure, systolic pressure, left ventricular ejection fraction (LVEF), E peak, A peak, E/A value of mitral flow, diastolic peak velocity (Vmax) and diastolic flow velocity time integrals (VTI) of left anterior descending coronary artery (LAD) in 11 healthy male subjects were measured before and after oral administration of GX II, using non-invasive echocardiogram.

RESULTSCompared with those before GX II administration, the changes after administration in heart rate, systolic pressure, diastolic pressure, LVEF, E peak, A peak and E/A value, were insignificantly different (P>0.05), but the Vmax and VTI significantly increased at 30 min, 60 min, 90 min and 120 min after GX II administration (P<0.05).

CONCLUSIONTo increase the coronary blood flow is possibly one of the mechanisms of GX II in treating coronary heart disease and angina pectoris.

Adolescent ; Adult ; Blood Flow Velocity ; drug effects ; Coronary Circulation ; drug effects ; Coronary Disease ; drug therapy ; Coronary Vessels ; drug effects ; ultrastructure ; Diastole ; drug effects ; Drugs, Chinese Herbal ; pharmacology ; Echocardiography ; Heart Rate ; drug effects ; Humans ; Male ; Middle Aged ; Systole ; drug effects ; Vasodilator Agents ; pharmacology ; Ventricular Function, Left ; drug effects

OBJECTIVETo study the effects of enhanced external counterpulsation (EECP) on the vascular morphology, and endothelial function using experimentally induced hypercholesterolemic pigs.

METHODSThirty five male pigs were randomly divided into three groups: 7 normal control animals, 11 hypercholesterolemic animals, and 17 hypercholesterolemic animals receiving EECP. Serum cholesterol was measured. The coronary arteries and aortas were sampled for histopathologic and ultrastructural examination. The NF-kappaB protein expression of porcine coronary arteries was investigated by immunofluorescence.

RESULTSCompared with the normal controls, serum cholesterol levels were significantly higher in the hypercholesterolemic animals with or without EECP. The plaque/intimal area ratio of the aorta decreased significantly in animals receiving EECP [(3.33 +/- 2.40)%, versus (12.03 +/- 7.12)% in those without EECP, P < 0.05]. Lipid deposition, endothelial damage and proliferation of smooth muscle cells were less severe in animals receiving EECP than those not. Moreover, activation and expression of NF-kappaB also decreased significantly (P < 0.05) in animals receiving EECP.

CONCLUSIONSEECP improves the morphology and function of vascular endothelium, and retards the development and progression of atherosclerosis, likely through the inhibition of NF-kappaB signaling pathway.

Animals ; Aorta, Abdominal ; metabolism ; pathology ; ultrastructure ; Atherosclerosis ; blood ; metabolism ; pathology ; Cholesterol ; blood ; Coronary Vessels ; metabolism ; pathology ; ultrastructure ; Counterpulsation ; methods ; Endothelial Cells ; metabolism ; pathology ; Hypercholesterolemia ; blood ; metabolism ; pathology ; Lipoproteins, LDL ; blood ; Male ; Microscopy, Confocal ; Microscopy, Electron, Scanning ; Microscopy, Electron, Transmission ; Muscle, Smooth, Vascular ; metabolism ; pathology ; NF-kappa B ; metabolism ; Random Allocation ; Swine