THE LYMPHATIC SYSTEMS

Dyah Purnaning

ANATOMY DEPARTMENT UNIVERSITY OF MATARAM

THE LYMPHATIC SYSTEMSConsists of two semi-independent parts

A meandering network of lymphatic vessels

Lymphoid tissues and organs scattered throughout the body

THE LYMPHATIC SYSTEMSincludes :lymphlymphatic vesselslymphatic tissuelymphatic noduleslymph nodestonsilsspleenthymus

THE LYMPHATIC SYSTEMS

Functions

helps to maintain fluid balance in tissues

absorb fats from the digestive tract

part of the bodys defense system against microorganisms and other harmful substances.THE LYMPHATIC SYSTEMS

1. Fluid balance

Approximately 30 L of fluid pass from the blood capillaries into the interstitial fluid each day.

Only 27 L pass from the interstitial fluid back into the blood Capillaries.

THE LYMPHATIC SYSTEMS

The 3 L of fluid enters the lymphatic capillaries the fluid is called lymph passes through the lymphatic vessels back to the blood THE LYMPHATIC SYSTEMS

THE LYMPHATIC SYSTEMS

2. Fat absorption.

The lymphatic system absorbs fats and other substances from the digestive tract.

Special lymphatic vessels called lacteals are located in the lining of the small intestine (villus).THE LYMPHATIC SYSTEMS

Fat absorption.

Fats enter the lacteals and pass through the lymphatic vessels to the venous circulation.

The lymph passing through these lymphatic vessels has a milky appearance because of its fat content and is called chyleTHE LYMPHATIC SYSTEMS

3. Body`s Defense.

Microorganisms and other foreign substances are filtered from lymph by lymph nodes and from blood by the spleen. THE LYMPHATIC SYSTEMS

In addition to water, LYMPH contains solutes derived from two sources:

substances in plasma, such as ions, nutrients, gases, and some proteins that pass from blood capillaries into the interstitial fluid

(2)substances derived from cells, such as hormones, enzymes, and waste productsTHE LYMPHATIC SYSTEMS

Main structures of the lymphatic system Lymphatic vessels Lymphatic vessels collect tissue fluid from loose connective tissue Carry fluid to great veins in the neck Fluid flows only toward the heartTHE LYMPHATIC SYSTEMS

LYMPHATIC VESSELS

FUNCTIONS

Collect excess tissue fluid and blood proteins

Return tissue fluid and blood proteins to bloodstreamLYMPHATIC VESSELS

Lymph capillariesSmallest lymph vessels, first to receive lymphLymphatic collecting vesselsCollect from lymph capillariesLymph nodesScattered along collecting vesselsLymph trunksCollect lymph from collecting vesselsLymph ductsEmpty into veins of the neckLYMPHATIC VESSELS

LYMPHATIC CAPILLARIESLymph capillariesSmallest lymph vessels (dead-end tubes) Located near blood capillariesFirst to receive lymphLymphatic capillaries are in almost all tissues of the body.Except :The central nervous system, The bone marrow, Tissues without blood vessels such as cartilage, epidermis, and the cornea.Lacteals specialized lymphatic capillaries, Located in the villi of the small intestines (Receive digested fats Fatty lymph /chyle)

Location and Structure of Lymphatic CapillariesLYMPHATIC CAPILLARIES

Lymphatic capillaries differ from blood capillaries :

Lymphatic capillaries lack a basement membrane

The cells of the simple squamous epithelium slightly overlap and are attached loosely to one anotherLYMPHATIC CAPILLARIES

Two things occur as a result of this structure.

First, the lymphatic capillaries are far more permeable than blood capillaries, and nothing in the interstitial fluid is excluded from the lymphatic capillaries Highly permeability allows entrance of Tissue fluid, Bacteria, viruses, and cancer cellsLYMPHATIC CAPILLARIES

2.Second, the lymphatic capillary epithelium functions as a series of one-way valves that allow fluid to enter the capillary but prevent it from passing back into the interstitial spaces.LYMPHATIC CAPILLARIES

LYMPHATIC CAPILLARIESLocation and Structure of Lymphatic Capillaries

LYMPHATIC COLLECTING VESSELSAccompany blood vesselsComposed of the same three tunics as blood vesselsThe inner layer of the lymphatic vessel consists of endothelium surrounded by an elastic membraneThe middle layer consists of smooth muscle cells and elastic fibersThe outer layer is a thin layer of fibrous connective tissue.

LYMPHATIC COLLECTING VESSELSTo helps direct the flow of blood Contain more valves than veins do

Lymph propelled byBulging of skeletal musclesPulsing of nearby arteriesTunica media of the lymph vessels

LYMPH NODES

Cleanse the lymph of pathogensHuman body contains around 500 Lymph nodes are organized in clusters

FUNCTIONSfilter the lymph preventing the spread of microorganisms and toxins that enter interstitial fluids.destroy bacteria, toxins, and particulate matter through the phagocytic action of macrophages.produce antibodies through the activity of B cells.LYMPH NODES

Microscopic Anatomy of a Lymph NodeFibrous capsule surrounds lymph nodesTrabeculae connective tissue strandsLymph vesselsAfferent lymphatic vesselsEfferent lymphatic vesselsLYMPH NODES

LYMPH NODES

LYMPH NODES

LYMPH TRUNKSLymphatic collecting vessels converge (after passing the lymph nodes)

LYMPH TRUNKSFive major lymph trunks Lumbar trunkReceives lymph from lower limbs, pelvic and abdominal walls, pelvic organs, ovaries or testes, kidneys, and adrenal glands2. Intestinal trunkReceives chyle from digestive organs (stomach, pancreas, spleen, and liver)3. Bronchomediastinal trunksCollects lymph from thoracic viscera (thoracic organs and the deep thoracic wall)

LYMPH TRUNKSFive major lymph trunks cont

4. Subclavian trunksReceive lymph from upper limbs, superficial thoracic wall, and mammary glands5. Jugular trunksDrain lymph from the head and neck

LYMPH TRUNKS

LYMPH DUCTSThe lymphatic trunks connect to large veins in the thorax or join to yet larger vessels called lymphatic ducts.

LYMPH DUCTSCisterna chyliLocated at the union of lumbar and intestinal trunks

Thoracic ductAscends along vertebral bodiesEmpties into venous circulation Junction of left internal jugular and left subclavian veinsDrains three quarters of the body

Right lymphatic duct Empties into right internal jugular and subclavian veins

Lymphatic ducts then connect to the large veins

The connections of the lymphatic trunks and ducts to veins are quite variable Many connect at the junction of the internal jugular and subclavian veins, but connections on the subclavian, jugular, and even brachiocephalic vein exist.LYMPH DUCTS

LYMPH DUCTS

On the right side, the jugular, subclavian, and bronchomediastinal trunks typically join a thoracic vein separately.

About 20% of the time, the three trunks join together to form a short duct 1 cm in length called the right lymphatic duct which joins a thoracic vein

These trunks drain the right side of the head, right-upper limb, and right thorax

The right side of the body inferior to the thorax and the entire left side of the body mostly drain through the thoracic ductLYMPH DUCTS

LYMPH DUCTS

Overview of the Lymph Nodes, Trunks, and Ducts

DISORDERS OF THE LYMPHATIC SYSTEMSChylothorax- Leakage of fatty lymph into the thoraxLymphadenitis- is an inflammation of the lymph nodes, which causes them to become enlarged and tender. This inflammation is an indication that microorganisms are being trapped and destroyed within the lymph nodesLymphangitis- Inflammation of a lymph vessel

Lymphoma- is a neoplasm (tumor) of lymphatic tissue- typically, lymphomas begin as an enlarged, painless mass of lymph nodes. The immune system is depressed, and the patient has an increased susceptibility to infections.

1. Hodgkins 2. Non-Hodgkins DISORDERS OF THE LYMPHATIC SYSTEMS

Elephantiasisis caused by long, slender roundworms (Wuchereria bancrofti). The adult worms lodge in the lymphatic vessels and block lymph flow. The resulting accumulation of fluid in the interstitial spaces and lymphatic vessels can cause permanent swelling and enlargement of a limb.

DISORDERS OF THE LYMPHATIC SYSTEMS

SELAMAT BELAJAR(^_^)