Cellular Components of Blood: Red Blood Cells

Differential cell count (diff)

After the smear is stained a veterinary technician can manually count each white blood cell type

The complete blood count is also known as the...

Hemogram or CBC. It is used to evaluate plasma proteins, red blood cells, white blood cells, and platelets. The CBC is one of the most useful clinical evaluations performed on a patient

Erythrocytes

RBC - mature red blood cells

Membrane deformability refers to...

The flexibility of the cell membrane, allowing it to change shape to travel through the various blood vessels in the body.

Reticulocyte Count (Retic)

a count of the number of immature forms of the red blood cells per a specific total number of red blood cells. This count is used to characterize the type of anemia in an animal.

Mean corpuscular hemoglobin concentration (MCHC) is...

another parameter that is clinically helpful to evaluate the erythrocytes in the presence of anemia. It measures the ratio of the weight of hemoglobin to the volume of red blood cells.

The total leukocyte count (WBC count)

expresses the total number of white blood cells in a specific volume of blood. The number of each type of white blood cell is also counted either by an automated blood analyzer or by evaluating a stained blood smear.

Oxyhemoglobin

hemoglobin bound to oxygen

Deoxyhemoglobin

hemoglobin without oxygen

PCV or HCT

packed cell volume (hematocrit)

Senescence

process of aging

Total plasma protein (TP) measures...

the amount of protein in the plasma portion of a specific volume of blood

The mean corpuscular volume (MCV) measures...

the average volume or size of the individual red blood cells. It is a helpful way to evaluate the erythrocytes in the sample, especially when anemia is present.

Hemoglobin (Hgb) analysis measures...

the concentration of hemoglobin contained in the red blood cells in a specific volume of blood.

The red blood cell count (RBC count) measures...

the number of red asures blood cells in a specific volume of blood. It is reported as the RBC count.

Describe the aging/destruction process of RBC

As a red blood cell becomes senescent, its enzyme activity decreases and the cell membrane loses its deformability by becoming rounder, enclosing a smaller volume. Approximately 1% of aging, dead, or abnormal red blood cells are removed from circulation and destroyed every day. This may occur intravascularly or extravascularly.

Extravascular Hemolysis

Destruction of red blood cells outside the cardiovascular system Ninety percent of the destruction of senescent red blood cells occurs by extravascular hemolysis

Intravascular Hemolysis

Destruction that takes place within blood vessels

Red Cell Distribution Width (RDW)

Determines the range of sizes of RBCs. The variation in size from cell to cell in a blood sample is called anisocytosis. Marked anisocytosis can be seen in cases of severe anemia where the bone marrow is pumping RBCs out at such a high rate they don't have time to mature fully. These immature RBCs are larger than a fully mature RBC already in circulation.

What is the life span of a RBC

Dogs - 120 days Cats - 68 days Horse & Sheep - live up to 150 days Cows - can live as long as 160 days. On the other end of the scale are mice, whose red blood cells live only 20 to 30 days. As red blood cells wear out, age, and die, they are replaced by young red blood cells from the red bone marrow in the never-ending erythropoiesis cycle.

The platelet count (PLT) measures...

the total number of platelets (thrombocytes) in a specific volume of blood sample. Thrombocytosis and thrombocytopenia are used to describe a higher than normal or lower than normal platelet count, respectively

What is the PCV

the volume of packed erythrocytes measured and expressed as a percentage of a total volume of blood.

What are the 3 main functions of RBC

1. Transporting oxygen to tissues. RBCs are able to perform this function using hemoglobin, a protein that is formed during RBC development The heme unit is the pigmented portion of hemoglobin. Each heme unit contains an iron atom (Fe2+) to which one oxygen molecule can attach. Therefore, one hemoglobin molecule can carry four molecules of oxygen. 2. Transporting carbon dioxide to the lungs. When the RBCs reach the tissue cells, there is an exchange of oxygen and carbon dioxide. Oxygen is taken from the hemoglobin in the RBCs by the cells in the tissues. At the same time, carbon dioxide, along with other metabolic waste, is released into the blood where it breaks down into ions that are transported to the lungs. 3. Maintaining cell shape and deformability. It is important for a red blood cell to maintain its biconcave disc shape. This shape provides more membrane surface area for the diffusion of oxygen and carbon dioxide. Also, it allows for a shorter diffusion distance in and out of the cell.

Describe the structure of an RBC in detail

(RBCs), also known as erythrocytes, are highly specialized cells that lack a nucleus, mitochondria, and ribosomes, but contain water, hemoglobin, and other structural elements. Since they have no mitochondria, erythrocytes utilize glucose from plasma for energy.