Background/Aim. The main complication of the atherosclerotic abdominal aortic
aneurism (AAA) is her rupture that begins with lesion in intima and rupture.
The purpose of this work was to determine immunocytochemical and
morphofunctional characteristics of the cells in aortic wall in ruptured
atherosclerotic abdominal aortic aneurysm. Method. During the course of this
study, 20 samples of atherosclerotic AAA were analyzed, all of them obtained
during authopsy. The samples were fixed in 4% formalin and embedded in
paraffin. Sections of 5 ?m thickness were stained histochemically (of
Heidenhain azan stain and Periodic acid Schiff - PAS stain) and
immunocytochemically using a DAKO LSAB+/HRP technique to identify ?-smooth
muscle actin (?-SMA), vimentin, myosin heavy chains (MHC), desmin, S-100
protein, CD45 and CD68 (DAKO specification). Results. The results of our
study showed that ruptured atherosclerotic AAA is characterized by a complete
absence of endothelial cells, the disruption of basal membrane and internal
elastic lamina, as well as a presence of the remains of hypocellular
complicated atherosclerotic lesion in intima. On the plaque margins, as well
as in the media, smooth muscle cells (SMCs) are present, which express a
?-SMA and vimentin (but without MHC or desmin expression), as well as
leukocyte infiltration, and a large number of foam cells. Some of the foam
cells show a CD68-immunoreactivity, while the others show vimentin- and S-100
protein-immunoreactivity. Media is thinned out with a disorganized elastic
lamellas, while adventitia is characterized by inflammatory inflitrate
(infection). Conclusion. Rupture of aneurysm occurs from the primary intimal
disruption, which spreads into thinned out media and adventitia. Rupture is
caused by unstable atherom, hypocellularity, loss of contractile
characteristics of smooth muscle cells in intima and media,
neovascularization of the media, as well as by the activity of the
macrophages in the lesion.
ESTROGEN STABILIZES MITOCHONDRIAL MEMBRANE POTENTIAL IN ANGIOTENSIN-II CHALLENGED PORCINE AORTIC SMOOTH MUSCLE CELLS: RELEVANCE TO THE LOWER INCIDENCE AND LATER ONSET OF ABDOMINAL AORTIC ANEURYSM IN WOMEN