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Blood and Lymph Vascular Systems

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Blood and Lymph Vascular Systems BLOOD AND LYMPH VASCULAR SYSTEMS BLOOD TRANSFUSIONS Objectives Functions of vessels Layers in vascular walls Classification of vessels Components of vascular walls Control of blood flow in microvasculature Variation in microvasculature Blood barriers Lymphatic system Introduction Multicellular Organisms Need 3 Mechanisms --------------------------------------------------------------- 1. Distribute oxygen, nutrients, and hormones CARDIOVASCULAR SYSTEM 2. Collect waste 3. Transport waste to excretory organs CARDIOVASCULAR SYSTEM Cardiovascular System Component function Heart - Produce blood pressure (systole) Elastic arteries - Conduct blood and maintain pressure during diastole Muscular arteries - Distribute blood, maintain pressure Arterioles - Peripheral resistance and distribute blood Capillaries - Exchange nutrients and waste Venules - Collect blood from capillaries (Edema) Veins - Transmit blood to large veins Reservoir Larger veins - receive lymph and return blood to Heart, blood reservoir Cardiovascular System Heart produces blood pressure (systole) ARTERIOLES – PERIPHERAL RESISTANCE Vessels are structurally adapted to physical and metabolic requirements. Vessels are structurally adapted to physical and metabolic requirements. Cardiovascular System Elastic arteries- conduct blood and maintain pressure during diastole Cardiovascular System Muscular Arteries - distribute blood, maintain pressure Arterioles - peripheral resistance and distribute blood Capillaries - exchange nutrients and waste Venules - collect blood from capillaries (edema) Cardiovascular System Veins - transmit blood to large veins reservoir Larger veins - receive lymph and return blood to heart, blood reservoir Volume: 5-6 l = 12-13 pints/ person Classification of Vessel Size (caliber) Prominent structures in wall Function Layers In Vascular Wall Layer Composition Tunica Intima Endothelium (Subendothelia ct. Internal elastic Lamina) Tunica media Smooth muscle (elastic lamellae, external elastic lamina) Tunica Connective Tissue Adventitia (longitudinal smooth muscle, vasa vasorum) Layers in vascular wall Muscular Artery Tunica Intima Tunica Media Tunica Adventitia Elastic Artery Tunica Intima Tunica Media Tunica Adventitia Elastic artery (human aorta) Tunica Intima Tunica Media Elastic Arteries Elastic Artery 248 Lots of elastic tissue to help maintain pressure during diastole Elastic artery Muscular artery Tunica Intima Tunica Media Tunica Adventitia Muscular artery (smooth muscle cells in tunica media) Arteriole Arteriole Arterioles Arteriole Arteriole - Capillary - Venule Capillary Pericyte Capillary Pericyte UT 166 VENULE Venule Venule Collect blood from capillaries (edema) Arteriole Capillary Venule Venule Venule Note difference in density of smooth muscle cells. Venule Muscular Artery Small Vein Large Vein Large Vein 196 TUNICA INTIMA TUNICA MEDIA TUNICA ADVENTITIA Cardiac Muscle Cardiac Muscle Intercalated disc Cardiac muscle Intercalated disc Fascia Adherens Maculae Adherens Gap junctions Lateral portion Intercalated Disc Cardiac Muscle is Striated Muscle Cardiac Muscle Cardiac Muscle - Diad Cardiac Muscle mitochondria Cardiac Muscle PURKINJE FIBERS Cardiac Muscle PURKINJE FIBERS PURKINJE FIBERS PURKINJE FIBERS Vasa Vasorum VESSEL OF VESSELS THE CORONARY ARTERY IS A VASA VASORUM CONTROL OF BLOOD FLOW: TONE MUSCULAR ARTERY Tone – state of partial contraction of smooth muscles in arteries and veins that reduces the caliber of the lumen. Innervations of Normal No smooth muscle cells nervous nervous of blood vessels control control controls the tone. Control Of Blood Flow Through Microvasculature Arterioles Precapillary sphincters Metarterioles Arteriolar Functions Allow sufficient pressure for flow through capillaries Low enough pressure to prevent damage Constant intermittence of blood flow to capillary beds Autoregulation - smooth muscle cells in arterioles and in pre-capillary sphincters respond to metabolic needs, low o2 tension, then relax increased blood flow (independent of nervous system) Endothelium - active cell Has enzymes and receptors Transport without much energy Flat for less turbulence Negatively charged surface Not wetable surface Methods of transport through capillary walls Diffusion Vesicle transport Channels between junctions Types of capillaries & basal lamina characteristics Capillaries basal lamina examples of locations Continuous complete muscle, testis, brain, Thymus Fenestrated complete glomerulus, adrenal Discontinuous incomplete or liver, spleen, bone Or sinusoidal lacking marrow MUSCLE GLOMERULUS LIVER Continuous Fenestrated Sinusoidal Continuous Fenestrated Fenestrated Sinusoidal Continuous (gut) Sinusoidal Angiogenesis – growth of blood vessels Mesenchymal cells Endothelial cells Smooth muscle cells Fibroblasts Angiogenesis Vascular Valves Location - medium caliber veins (especially extremities) Collecting and lymphatic ducts Function - insure unidirectional flow Composition flap or leaflet which are folds of The intima with reinforcements of connective tissue Vascular Valve Heart Heart Internodal connections Congestive Heart Failure Congestive heart failure (CHF), or heart failure, is a condition in which the heart can't pump enough blood to the body's other organs. This can result from narrowed arteries that supply blood to the heart muscle — coronary artery disease • Past heart attack, or myocardial infarction, with scar tissue that interferes with the heart muscle's normal work • High blood pressure • Heart valve disease due to past rheumatic fever or other causes • Primary disease of the heart muscle itself, called cardiomyopathy. • Heart defects present at birth — congenital heart defects. Congestive Heart Failure • Infection of the heart valves and/or heart muscle itself — endocarditis and/or myocarditis • The "failing" heart keeps working but not as efficiently as it should. People with heart failure can't exert themselves because they become short of breath and tired. • As blood flow out of the heart slows, blood returning to the heart through the veins backs up, causing congestion in the tissues. Often swelling (edema) results. Most often there's swelling in the legs and ankles, but it can happen in other parts of the body, too. Sometimes fluid collects in the lungs and interferes with breathing, causing shortness of breath, especially when a person is lying down. • Heart failure also affects the kidneys' ability to dispose of sodium and water. The retained water increases the edema. Variations in the Microvasculature Common Arteriole Capillary Venule Shunts Arteriole Metarteriole Venule Artery av shunt Vein Variations in the Microvasculature Venous portal system Capillary Portal Vein Capillary Arterial portal system Capillary Portal Arteriole Capillary Generic function of any Portal System Venous portal system Arterial portal system Function of portal system? Modify local blood composition with first capillary modifying blood composition and second distributing modified blood locally for benefit of target cells/tissues Arterial portal system Capillary Portal Arteriole Capillary Blood barriers Type Source of Barrier Blood-brain Zonula Occludens of endothelium Blood-thymus Zonula Occludens of endothelium and sheath of epithelial reticulum Blood-testis Occluding junctions between sertoli cells in Seminiferous tubules Typical Endothelial Tight Junction and Marginal Fold Blood-Brain Barrier Typical Blood-Thymus Barrier Zonula Occludens of endothelium and sheath of epithelial reticulum Occluding junctions between sertoli cells Blood-testis barrier occluding junctions between sertoli cells in seminiferous tubules Lymph vessels Functions return protein, fluid, and blood cells Lymph vessels Functions return protein, fluid, and blood cells Transport secretions (hormones, antibodies) Transport fat (neutral fat) Lymph vessels Transport across transit vesicles Capillaries Intercellular junctions Lymph vessels Lymph flow – Compression of lymphatic vesicles (muscles, pulsating blood vessels) Unidirectional flow – Controlled by valves Flow rate – Remarkably rapid Anchoring device – Vessels open Age-related and/or disease- related changes in blood vessels Defect cause Arteriosclerosis elastic lamellae (hardening of replaced by other arteries) connective tissue elements Atherosclerosis patchy, irregular (heart attack and thickening of intima stroke) Function / actions of lysosomes Unprogrammed cell death Damage/death to cardiac cells in ischemia associated with myocardial infarctions Function / actions of lysosomes PRE-STENT POST-STENT Summary Vessels are structurally adapted to physical and metabolic requirements. Summary Vessels are structurally adapted to physical and metabolic requirements. Can you identify these? ? ? ? ? ? ? ? Next time Overview of The Immune System .
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