The Cardiovascular System Michael Hall Ph D University

The Cardiovascular System Michael Hall Ph. D. University of California Los Angeles

cailey@ucla. edu

The Cardiovascular System pulmonary artery pulmonary vein vena cava

Epithelium and Endothelium

Types of Epithelium Endothelium is a specialized simple squamous epithelium

Endothelium lines all blood vessels Endothelium Smooth muscle

The role of endothelial cells in diapedesis

The Heart

SVC Head and arms Aorta R. lung LA RA LV Septum IVC RV Trunk and legs

Epicardium The Heart Wall e Myocardium d ui Epicardium Myocardium c pa s Fl Endocardium Pericardium Atrium Endocardium Inside

Heart valves

Heart valve Valve E F Valve chordae tendinae E

Heart valves and supporting fibrous skeleton Valves Fibrous skeleton Cardiac muscle (myocardium)

Conducting System

Conducting system of the heart

Endocardium Purkinje cells make up the Purkinje fibers, which constitute part of the conducting system of the heart Cardiac muscle fibers

Conducting system of the heart Bundle of His

Cardiac Muscle

Organization of Cardiac Muscle Intercalated disk disc myofibrils endomysium myofiber

Structure of a Cardiac Muscle Sarcomere Electron Micrograph Diagram

Z-disk d n a b I e er om rc sa Aba nd Cardiac Muscle

cardiac muscle

ID CT N Branching fibers Cardiac Muscle

Z-disk Fiber 1 Fiber 2 Fiber 3 Fiber 4 Structure of intercalated disc of cardiac muscle

Smooth Muscle

Smooth Muscle Cell

Smooth Muscle Sheet

Smooth Muscle

Small Artery with Smooth Muscle in tunica media Endothelium

Smooth Muscle Contraction

The distributing portion of the cardiovascular system The arteries and veins

General Structure of Artery and Vein T. Intima: Endothelium + Subendothelium + Elastic lamina T. Media: Smooth muscle Collagen Elastica T. Adventitia: Collagen Elastica Vasa vasorum

Structure of a typical Vein and Artery

Arteries

Elastic (conducting) artery (eg aorta) Muscular (distributing) artery (eg renal, splenic)

T. intima Elastic (conducting) artery T. media T. intima elastic laminae IEL T adventitia Muscular (distributing) artery T. media EEL T adventitia

Arteriole and venule V IEL A

Atherosclerosis: deposition of fat in the intima layer Leading cause of death in industrialized nations Death results from occlusion or rupture of arteries Prevalence is close to 100%

Capillaries

Capillaries Continuous Fenestrated Sinusoidal

Types of capillaries Continuous Fenestrated Sinusoidal

Capillary blood flow A-V anastomosis

Capillary functions 1. Selective permeability barrier: Exchange of nutrients 2. Metabolic functions: Effect on blood flow 1. Antithrombogenic effect: Prevention of blood clotting

Veins

Muscular artery and large vein

Large vein Medium vein eg. vena cava t. m t. i

Large vein TA TM Arterioles small vein/venule Small artery Venule

Contraction of skeletal and smooth muscle aid in the return of blood to the heart. Valves prevent backflow

Lymphatics

blood flow V

Capillary Exchange

Heart valve elastica Valve CT Valve chordae tendinae