Ultrastructure study of the transgenic REN2 rat aorta – part 2: media, external elastic lamina, and adventitia

1.Patients with an elevated plasma level of either homocysteine or cholesterol are at increased risk of cardiovascular disease. Both methionine, the precursor of homocysteine, and cholesterol are found primarily in the same foods; therefore we investigated the effect of methionine feeding alone, cholesterol feeding alone, and both, on the thickness of the aortic wall and the aortic elastic lamina of normotensive animals. 2.Twenty normotensive rats were divided into four groups of five animals. The following diet was administered for 15 weeks: normal chow; normal chow supplemented with 2% methionine; normal chow supplemented with 2% cholesterol; normal chow supplemented with 2% methionine+2% cholesterol. 3.The results showed a 3-fold decrease (P< 0.003) in the aortic elastic lamina in the 2% methionine group and a 2.5-fold decrease in the 2% cholesterol group compared with the normal chow group. There was a 9-fold (P< 0.0003) decrease in the 2% methionine+2% cholesterol group compared with the normal chow group. Furthermore, feeding with methionine plus cholesterol significantly increased aortic wall thickness compared with the methionine group, cholesterol group or control. 4.These results demonstrate an augmented effect of cholesterol plus methionine in the deterioration of the aortic elastic lamina, and furthermore, the combination of these two agents increases the thickness of the aortic wall. The results indicate a more important role for these two agents in combination than for either agent alone.

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Ultrastructure Study of Transgenic Ren2 Rat Aorta – Part 1: Endothelium and Intima

Cardiorenal Medicine ◽

10.1159/000335565 ◽

2012 ◽

Vol 2 (1) ◽

pp. 66-82 ◽

Cited By ~ 5

Author(s):

Melvin R. Hayden ◽

Javad Habibi ◽

Tejaswini Joginpally ◽

Poorna R. Karuparthi ◽

James R. Sowers

Keyword(s):

Rat Aorta ◽

Ultrastructure Study

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Ultrastructure and Staining of Developing Elastic Tissue

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100065274 ◽

1971 ◽

Vol 29 ◽

pp. 244-245

Author(s):

E. N. Albert

Keyword(s):

Fine Structure ◽

Phosphotungstic Acid ◽

Staining Method ◽

Rat Aorta ◽

Uranyl Acetate ◽

The Other ◽

Elastic Fibers ◽

Elastic Tissue ◽

Lead Citrate ◽

New Born

Silver tetraphenylporphine sulfonate (Ag-TPPS) was synthesized in this laboratory and used as an electron dense stain for elastic tissue (Fig 1). The procedures for the synthesis of tetraphenylporphine sulfonate and the staining method for mature elastic tissue have been described previously.The fine structure of developing elastic tissue was observed in fetal and new born rat aorta using tetraphenylporphine sulfonate, phosphotungstic acid, uranyl acetate and lead citrate. The newly forming elastica consisted of two morphologically distinct components. These were a central amorphous and a peripheral fibrous. The ratio of the central amorphous and the peripheral fibrillar portion changed in favor of the former with increasing age.It was also observed that the staining properties of the two components were entirely different. The peripheral fibrous component stained with uranyl acetate and/or lead citrate while the central amorphous portion demonstrated no affinity for these stains. On the other hand, the central amorphous portion of developing elastic fibers stained vigorously with silver tetraphenylporphine sulfonate, while the fibrillar part did not (compare figs 2, 3, 4). Based upon the above observations it is proposed that developing elastica consists of two components that are morphologically and chemically different.

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Anchoring Fibrils in Arterial Endothelium

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100063287 ◽

1969 ◽

Vol 27 ◽

pp. 274-275

Author(s):

A. Trillo

Keyword(s):

Carotid Arteries ◽

Animal Species ◽

Cell Layer ◽

Present Communication ◽

Internal Elastic Lamina ◽

Endothelial Cell Layer ◽

Structural Details ◽

Rats And Mice ◽

Arterial Endothelium ◽

Elastic Lamina

There are conflicting reports regarding some fine structural details of arteries from several animal species. Buck denied the existence of a sub-endothelial space, while Karrer and Keech described a space of variable width which separates the endothelium from the underlying internal elastic lamina in aortas of aging rats and mice respectively.The present communication deals with the ultrastrueture of the interface between the endothelial cell layer and the internal elastic lamina as observed in carotid arteries from rabbits of varying ages.

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Targeting Platelets Containing Electro-encapsulated lloprost to Balloon Injured Aorta in Rats

Thrombosis and Haemostasis ◽

10.1055/s-0038-1653809 ◽

1995 ◽

Vol 73 (03) ◽

pp. 535-542 ◽

Cited By ~ 1

Author(s):

N Crawford ◽

A Chajara ◽

G Pfliegler ◽

B EI Gamal ◽

L Brewer ◽

...

Keyword(s):

Time Course ◽

Therapeutic Potential ◽

Simple Procedure ◽

Rat Aorta ◽

Balloon Injury ◽

Post Injury ◽

Antiproliferative Effects ◽

Platelet Deposition ◽

Total Dna ◽

Novel Drug

SummaryDrugs can be electro-encapsulated within platelets and targeted to damaged blood vessels by exploiting the platelet’s natural haemostatic properties to adhere to collagen and other vessel wall constituents revealed by injury. A rat aorta balloon angioplasty model has been used to study the effect on platelet deposition of giving iloprost loaded platelets i.v. during the balloon injury. After labelling the circulating platelets with 111-Indium before balloon injury, time course studies showed maximum platelet deposition on the injured aorta occurred at about 1 h post-injury and the deposition remained stable over the next 2-3 h. When iloprost-loaded platelets were given i.v. during injury and the circulating platelet pool labelled with 111-Indium 30 min later, platelet deposition, measured at 2 h postinjury, was substantially and significantly reduced compared with control platelet treatment. Some antiproliferative effects of iloprost-loaded platelets given i.v. during injury have also been observed. Whereas the incorporation of [3H]-thymidine into aorta intima-media DNA at 3 days post injury was 62-fold higher in balloon injured rats than in control sham operated rats, thymidine incorporation into intima/media of rats which had received iloprost loaded platelets during injury was reduced as compared with rats subjected only to the injury procedure. The reduction was only of near significance, however, but at 14 days after injury the total DNA content of the aorta intima/media of rats given iloprost loaded platelets during injury was significantly reduced. Although iloprost loaded platelets can clearly inhibit excessive platelet deposition, other encapsulated agents may have greater anti-proliferative effects. These studies have shown that drug loaded platelets can be targeted to injured arteries, where they may be retained as depots for local release. We believe this novel drug delivery protocol may have therapeutic potential in reducing the incidence of occlusion and restenosis after angioplasty and thrombolysis treatment. Electro-encapsulation of drugs into platelets is a simple procedure and, using autologous and fully biocompatible and biodegradable platelets as delivery vehicles, might overcome some of the immunological and toxicological problems which have been encountered with other delivery vectors such as liposomes, microbeads, synthetic microcapsules and antibodies.

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