cardiovascular system blood vessels
DESCRIPTION
CARDIOVASCULAR SYSTEM BLOOD VESSELS. General Organization Arteries Large (Elastic) Arteries Muscular (Distributing) Arteries Arterioles (Small) Arteries Precapillary (Terminal) Arterioles Capillaries Veins Venules Medium Veins Large Veins Lymphatics. General Organization. - PowerPoint PPT PresentationTRANSCRIPT
CARDIOVASCULAR SYSTEMBLOOD VESSELS General OrganizationGeneral Organization ArteriesArteries
Large (Elastic) ArteriesLarge (Elastic) Arteries Muscular (Distributing) ArteriesMuscular (Distributing) Arteries Arterioles (Small) ArteriesArterioles (Small) Arteries Precapillary (Terminal) ArteriolesPrecapillary (Terminal) Arterioles
CapillariesCapillaries VeinsVeins
VenulesVenules Medium VeinsMedium Veins Large VeinsLarge Veins
LymphaticsLymphatics
General Organization
Blood Vascular SystemPortal SystemLymph Vascular
System
Tissue Components
EndotheliumElastic elementsMuscular elementsConnective tissue
elements
Arteries - General Structural PlanTunica IntimaTunica MediaTunica
Adventitia
Arteriosclerosis
Tunica Intima
EndotheliumBasement membraneSubendothelial connective
tissueInternal elastic lamina (IEL)
Tunica Media
Smooth muscle Elastic fibers/lamina
Tunica Adventitia
External elastic lamina (EEL)
Connective tissueVasa vasorumSympathetic nerves
Arteriosclerosis - “Hardening of Art.”
AtherosclerosisMonckeberg’s Medical Calcific
SclerosisArteriolosclerosis
Myointimal Cells
Intimal smooth muscle cells
Potential of fibroblasts, macrophages & SM
Foam cells (lipophages)
BV CLASSIFICATIONS ArteriesArteries
Large (Elastic)Large (Elastic) Medium (Muscular)Medium (Muscular) Small (Arterioles)Small (Arterioles)
CapillariesCapillaries ContinuousContinuous Sinusoids Sinusoids Lymphatics Lymphatics
VeinsVeins Small (Venules)Small (Venules) MediumMedium Large (Cava)Large (Cava)
Large (Elastic) ArteriesTunica intimaTunica intima
thicker subendothelial c.t.thicker subendothelial c.t.poorly defined IELpoorly defined IEL
Tunica mediaTunica media - thickest, largely elastic - thickest, largely elasticTunica adventitiaTunica adventitia
EEL poorly definedEEL poorly definedvasa vasorumvasa vasorum
Muscular (Distributing) Arteries
Tunica intimaTunica intima - thin with prominent IEL - thin with prominent IELTunica mediaTunica media - largely smooth muscle - largely smooth muscleTunica adventitiaTunica adventitia
thick with prominent EELthick with prominent EELvasa vasorum, lymphatics, nervesvasa vasorum, lymphatics, nerves
Arterioles (Small Arteries)
Tunica intimaTunica intima - absence of IEL - absence of IEL Tunica mediaTunica media - gradual reduction in layers - gradual reduction in layersTunica adventitiaTunica adventitia - no EEL - no EEL
Precapillary (Terminal) Arterioles
MetarteriolesMetarteriolesno IELno IEL1-2 smooth muscle cells1-2 smooth muscle cellsserve as AV shuntsserve as AV shunts true capillaries are branchestrue capillaries are branches
Precapillary SphinctersPrecapillary Sphinctersguard openings of true capillariesguard openings of true capillaries
Capillaries - General Structural Plan
EndotheliumEndothelium Basement Memb.Basement Memb. PericytesPericytes Other CellsOther Cells
Endothelium
Cells elongated along capillary axisCells elongated along capillary axisAttached by both occluding (tight) and Attached by both occluding (tight) and
communicating (gap) junctionscommunicating (gap) junctionsOval or elongated nucleus (bulges into lumen)Oval or elongated nucleus (bulges into lumen)Contractile - cytoplasmic filamentsContractile - cytoplasmic filamentsPinocytotic vesicles and vacuolesPinocytotic vesicles and vacuoles
Basement Membranes
Continuous in blood vascular system Continuous in blood vascular system (prominent in brain as BBB)(prominent in brain as BBB)
Discontinuous in sinusoids and lymphaticsDiscontinuous in sinusoids and lymphaticsCollagen Type IVCollagen Type IVElastic fibersElastic fibers
Pericytes
Enclosed in own basement membraneEnclosed in own basement membraneDiscontinuous and irregularly spacedDiscontinuous and irregularly spacedParticularly numerous in brain (BBB)Particularly numerous in brain (BBB)Nucleus bulges away from lumenNucleus bulges away from lumen
Other Cells
Fixed macrophagesFixed macrophagesMast cells - secrete heparinMast cells - secrete heparinRare nerve fibersRare nerve fibers
Capillary FunctionBarrierBarrier
Endocapillary layerEndocapillary layerEndotheliumEndotheliumBasal lamina and pericytesBasal lamina and pericytesAdventitiaAdventitia
Exchange ForcesExchange ForcesHydrostaticHydrostaticOsmoticOsmoticConcentrationConcentration
Capillaries - Structural Types
True CapillariesTrue CapillariesContinuous capillariesContinuous capillariesFenestrated capillaries with diaphragmsFenestrated capillaries with diaphragmsFenestrated capillaries without diaphragmsFenestrated capillaries without diaphragms
SinusoidsSinusoids Lymphatic CapillariesLymphatic Capillaries
Venules (Small Veins)
Tunica intima - endothelial tubeTunica intima - endothelial tube Tunica mediaTunica media
PericytesPericytesIsolated smooth muscle cellsIsolated smooth muscle cells
Tunica Adventitia - minimalTunica Adventitia - minimal
Medium Veins
Tunica intima - thin, forms valvesTunica intima - thin, forms valves Tunica media - scattered smooth muscle Tunica media - scattered smooth muscle
Inner layer longitudinally arranged in large veinsInner layer longitudinally arranged in large veins Tunica adventitia - thick with longitudinal Tunica adventitia - thick with longitudinal
Large Veins
Tunica intima - slightly thicker than mediumTunica intima - slightly thicker than medium Tunica media - sparse smooth muscle cellsTunica media - sparse smooth muscle cells Tunica adventitia - thick with longitudinal Tunica adventitia - thick with longitudinal
bundles of smooth muscle cellsbundles of smooth muscle cells
Lymphatics Tunica intima & adventitia onlyTunica intima & adventitia only Discontinuous basement membraneDiscontinuous basement membrane Very frequent valvesVery frequent valves Anchoring filamentsAnchoring filaments Extensive vasa vasorumExtensive vasa vasorum LymphangionLymphangion Interposed lymph node filters Interposed lymph node filters Drain into veinsDrain into veins
BV CLASSIFICATIONS ArteriesArteries
Large Large ElasticElastic laminalamina MediumMedium >10 SM layers>10 SM layers Small (Arterioles)Small (Arterioles) <5 SM layers<5 SM layers
CapillariesCapillaries Continuous Continuous (Fenestrated & Non-Fenestrated)(Fenestrated & Non-Fenestrated) Sinusoids Sinusoids (Liver, spleen, lymph nodes, BM)(Liver, spleen, lymph nodes, BM) Lymphatics Lymphatics (Everywhere)(Everywhere)
VeinsVeins Small (Venules)Small (Venules) Thin wall, large lumenThin wall, large lumen MediumMedium Few layers of SM, “Few layers of SM, “ Large (Cava)Large (Cava) Long. SM in Adv.Long. SM in Adv.