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Lymphatic systemThe lymphatic system consists of a fluid called lymph, vessels called lymph vessels, a series of
structures and organs containing lymph tissue and the red bone marrow, where stem cells develop into
blood cells, including lymphocytes.
Lymph flows via tubes known as lymphatic vessels. Tiny lymphatic channels in your tissues connect to
generate larger and larger lymphatic vessels, like how streams flow into rivers. They eventually discharge
into massive lymphatic tubes known as lymphatic ducts.
Lymph from the lymphatic ducts enters your circulation via major veins around your heart. This helps to
keep your blood pressure constant and reduces swelling by removing extra fluid from your body.
Your heart does not pump lymph around your body. It is instead propelled forward when your lymphatic
vessels are compressed by your muscles, as well as by gravity if the vessels are above your heart. Muscle
cells on the walls of lymphatic tubes also assist pressing the fluid along. Inside the arteries, one-way
valves prevent lymph from flowing backwards.
Formation of lymph:
If you answer the question "how is lymph formed", it is worth remembering the oncotic pressure. Thus,
high hydrostatic blood pressure promotes lymph formation, and high oncotic pressure inhibits this
process. The filtration of the fluid passes through the capillaries, and it returns to the venous canal as
there is a pressure difference at the venous and arterial end of the capillaries.
It is worth knowing that the permeability of lymph capillaries varies depending on the functional state of
the organs as well as under the influence of various mechanical, chemical as well as humoral or nervous
factors. The rate of lymph formation and its volume depends on the ratio of systemic to lymphatic
circulation
Some disorders can affect the overall lymphatic system like:
Lymphatic Filariasis
Filariasis is a parasitic infection with a thread-like roundworm that is found in tropical and subtropic
countries.
The disease is transmitted from person to person by mosquito bites. The adult worms can live for years in
the body's lymphatic system.
Eventually, the lymphatic pathways can be destroyed so that different parts of the body can swell up due
to decreased circulation of lymph fluid. In chronic disease, severe swelling can occur in the abdomen,
scrotum, legs and feet - so-called elephantiasis.
If the disease occurs acutely, you get episodes of fever with or without inflammation of the lymph nodes
and lymph nodes. The symptoms may occur at irregular intervals and last for several days. Typically, the
inflammation in the lymphatic vessels is seen to move away from the lymph nodes. This is the opposite of
what one sees in an inflammation with bacteria. As the disease spreads, inflammation can occasionally
occur in the epididymis and testicles and in the lymph nodes and lymph vessels in the pelvis and
abdominal cavity.
, Chronic disease occurs as a result of decreased / inhibited lymph circulation.
Diagnosis:
The disease is detected by the presence of larvae (microfilariae) in the blood, by positive antibody testing
or by the detection of adult worms by ultrasound.
Treatment:
There are several types of medications available to treat filariasis. Some preparations work primarily
against the adult worms in the lymphatic system, while other preparations mainly work by killing the
larvae in the blood. Therefore, the treatment almost always consists of two or three different preparations.
Hydrostatic and oncotic pressure:
The parapapillary circuit is the term for the circuit between capillaries and tissue cells. This is where the
capillary exchange takes place, by squeezing liquid with oxygen and dissolved nutrients, etc. out of the
capillary to the interstitial space at the arterial end of the capillary. Out in interstitial space, there is an
exchange of oxygen, nutrients, carbon dioxide and waste products across the cell membranes in the tissue
cells. Subsequently, the fluid with the new composition of solutes is withdrawn into the bloodstream at
the venous end of the capillary. Thus, oxygen and nutrients are constantly carried out to the cells, while
carbon dioxide and waste products are removed from the cells.
To understand this process, we must know that there are two opposing forces at play in the parapapillary
circuit. One is hydrostatic pressure, and the other is oncotic pressure.
The hydrostatic pressure
The hydrostatic pressure can be understood as the local blood pressure in the capillary. That is, the
pressure that is created by the heart's pumping work and pushes the blood out against the vessel wall.
The hydrostatic pressure is relatively constant, and is approx. 35 mmHg at the arterial end of the
capillary, and approx. 15 mmHg at the venous end of the capillary. On the other hand, the hydrostatic
pressure in the interstitial space is very low at approx. 2 mmHg. The hydrostatic pressure will therefore
try to force fluid out of the bloodstream.
The hydrostatic pressure is lower at the end of the capillary because the blood pressure is highest in the
aorta and decreases the further away from the aorta we move.
The oncotic pressure
The oncotic pressure is created by the colloids in the bloodstream. These colloids are made up of the
plasma proteins in the blood, of which albumin has the greatest influence on the oncotic pressure. The
plasma proteins are too large to be able to go in between the gaps in the capillaries and they therefore
remain in the bloodstream, where they maintain a relatively constant osmotic pressure throughout the
bloodstream of approx. 25 mmHg. On the other hand, the oncotic pressure in the interstitial space is very
low at approx. 1-2 mmHg. The oncotic pressure therefore acts as a "suction", and all other things being
equal, fluid will move in the direction of a high osmotic pressure. The oncotic pressure in the bloodstream
will therefore try to draw fluid into the bloodstream.
Absorption of fats from the digestive system:
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