Histology of CVS Flashcards
What does the epicardium consist of
Single layer of mesothelial cells and underlying connective tissues and adipose tissue
Blood vessels and nerves they supply the heart present in epicardium surrounded by apidose tissue
What does the myocardium consist of
Cardiac muscle
What does endocardium consist of
Endothelium consisting of simple squamous epithelial cells
Subendothelial layer of connective tissue consisting of collagen and elastic fibres and smooth muscle cells
Subendocardium consisting of loose connective tissue and branches of the purkinje
What is fibrosa
Ventricular surface of AV vales and arterial surface of SL valves
Covered by layer of endothelial cells
Composed primarily of densely packed type I and II collagen fibres and elastic fibres
What is the spongiosa
Middle layer of valve leaflet
Consists of loosely arranged collagen and elastic fibres surrounded by ground substances
What is ventricularis/atrialis
Immediately adjacent to ventricular/atrial surface of each valve
Covered with endothelium; dense connective tissue layer with collagen and elastic fibres
What is tunica intima
Innermost layer of the vessel
Consists of endothelium, subendothelial layer and elastic membrane
What is tunica media
Middle layer of the vessel
Consists primarily of vascular smooth muscle cells
What is tunica adventitia
Outermost connective tissue layer
Consists primarily of collagenous tissue and relatively few elastic fibres
Theee types of arteries
Large arteries
Medium arteries
Arterioles
What does tunica intima of large artery consist of
Endothelial lining with its basal lamina- single layer of squamous epithelial cells
Subendothelial layer - loose connective tissue containing collagen and elastic fibres smooth muscles cells
Internal elastic membrane
What does tunica media consist of in large arteries
Elastin in the form of fenestrated sheets or lamellae between muscle cell layers
Vascular smooth muscle cells arranged in layers
Collagen fibres and proteoglycans synthesised and secreted by the moth muscle cells
Tunica adventitia of the large arteries
Collagen and elastic fibres
Fibroblasts and macrophages
Vasa Vasorum
Tunica intima of medium arteries
Consists of endothelial lining with its basal lamina
Contains prominent internal elastic membrane
Thinner than TI in elastic arteries
Tunica adventitia of medium arteries
Relatively thick
Consists of fibroblasts collagen and elastic fibres and in some adipose tissue
Separated from TM by external elastic membrane
Contains vasa vasorum
Tunica media of medium arteries
Composed almost entirely of vascular smooth muscle cells arranged in spiral pattern
Cells scattered among collagen fibres
Contains very little elastic material
Tunica intima of small arteries/arterioles
Consists of endothelium and Subendothelial connective tissue
Small artery- internal elastic membrane present
Arteriole- internal elastic membrane may or may not be present
Tunica media of small arteries/arterioles
Smooth muscle cells arranged in layers
Tunica media of small arteries/arterioles
Smooth muscle cells arranged in layers
Tunica adventitia of small arteries/arterioles
Connective tissue containing collagen fibres and fibroblasts
Thin and undefined
what do venules contain
postcapillary - contain endothelial lining with a basal lamina and pericytes
muscular - contain one or two layers of vascular smooth muscle that constitutes a TM; have a thin TA
what do small veins constitute
TI, TM and TA all present
TM usually consists of two or three layers os vascular smooth muscle
have thicker TA compared to venules
tunica intima of medium veins
endothelium with basla lamina
subendothelial layer of connective tissue
internal elastic membrane sometimes oresent
tunica media of medium veins
several layers of smooth muscle cells in circular pattern, interspersed with collagen and elastic fibres
Tunica adventitia of medium veins
composed of collagen and elastic fibres thicker than TM
Tunica intima of large veins
endothelium with basal lamina
Small amount of subendothelial layer of connective tissue
some smooth muscle cells
tunica media of large veins
relatively thin
consists of circumferentially arranged smooth muscle cells, collagen fibres and fibroblasts
tunica adventitia of large veins
thickest layer, consists of collagen and elastic fibres, fibroblasts, smooth muscle cells
three types of capillaries
continuous
fenestrated
discontinous
what is continous capillaries
uninteruppted vasular endothelium resting on contious basal lamina
what is fenestrated capillaries
cells have opening called fenestrations; have continuous basal lamina
what are discontinous capillaries
cells have large openings, separated by wide irregular gaps
