plasma proteins and maintaining colloid osmotic pressure?

Question

Hi can anyone tell me how plasma proteins are involved with maintaining colloid osmotic pressure?

Answer 1

Eek. It's a bit hazy in my memory but I learned all that stuff at med school.

Basically the action of the heart pumping causes water to be pushed out of the capillaries into the tissues - this is hydrostatic pressure. To combat this, plasma proteins in the blood exert oncotic pressure, which means that water is drawn back into the blood vessels.

The balance of osmotic gradients and water movement in the body is influenced by a number of different methods in the body of homeostasis, such as dehydration. The capillaries have tiny holes in their walls which can become larger and allow protein to 'leak' out. The leakiness of capillaries is one way of the body modifying its water balance.

Hope that helps a bit.

Answer 2

yes.. it's basic osmosis my friend fluid has a tendecy to move across a semi-permiable membrane towards the more concentrated solution in order to balance the concentrations. The plasma proteins, primarily albumin (produced in the liver) and immunoglobulins (produced by the bone marrow) help to maintain this level. In diseases where the plasma protein concentrations are affected often an accumulation of fluid occurs in body compartments eg liver failure, where insufficient albumin in being produced. In other case such as myeloma a vast increase in immunoglobulin levels occur and so a down regulation of liver albumin production can be seen to balance the osmotic pressure.
Blood osmolarity is generally maintained with more sensitive and immediate adjustments in the contributing ions i.e. sodium, potassium, urea and glucose.

Answer 3

Because large plasma proteins can't easily cross through the capillary walls, their effect on the osmotic pressure of the capillary interiors will, to some extent, balance out the tendency for fluid to leak out of the capillaries. In conditions where plasma proteins are reduced, e.g. from being lost in the urine (proteinuria) or from malnutrition, the result of the too low oncotic pressure can be edema - excess fluid buildup in the tissues.

that's all I could find on the net...but I'll search else where..if i find something helpfull...I'll come back & add..

good luck

Answer 4

In addition to what others have said certain conditions such as sepsis and some poisons can alter capillary permeability causing proteins to leak out of the blood vessels into the tissues causing third spacing, hypovolemia and hypotension.

Answer 5

In english?

Answer 6

i wish i could but....... my blood runs cold