- Plural of granulocyte
Granulocytes are a category of white blood cells characterised by the presence of granules in their cytoplasm. They are also called polymorphonuclear leukocytes (PMN or PML) because of the varying shapes of the nucleus, which is usually lobed into three segments. In common parlance, the term polymorphonuclear leukocyte often refers specifically to neutrophil granulocytes, the most abundant of the granulocytes. Granulocytes or PMN are released from the bone marrow by the regulatory complement proteins.
ClassificationThere are three types of granulocytes, distinguished by their appearance under Wright's stain:
Their names are derived from their staining characteristics; for example, the most abundant granulocyte is the neutrophil granulocyte, which has neutrally-staining cytoplasmic granules.
Other white blood cells which are not granulocytes ("agranulocytes") are mainly lymphocytes and monocytes.
Toxic materials produced or releasedExamples of toxic materials produced or released by degranulation by granulocytes on the ingestion of microorganism includes:
- Low pH vesicles (3.5-4.0)
- Toxic oxygen-derived products (e.g. superoxide, hydrogen peroxide, hydroxy radicals, singlet oxygen, hypohalite)
- Toxic nitrogen oxides (nitric oxide)
- Antimicrobial agents (Defensins and cationic proteins)
PathologyGranulocytopenia is an abnormally low concentration of granulocytes in the blood. This condition reduces the body's resistance to many infections. Closely-related terms include agranulocytosis (no granulocytes at all) and neutropenia (deficiency of neutrophil granulocytes). Transfusion of granulocytes would have been a solution to the problem. However, granulocytes live only ~10 hours in the circulation (for days in spleen or other tissue), which gives a very short-lasting effect. In addition, there are many complications of such procedure.
There is usually a granulocyte chemotactic defect in individuals who suffer from insulin dependent diabetes mellitus.
Image:Illu blood cell lineage.jpg|Blood cell lineage Image:Hematopoiesis (human) diagram.png|Hematopoiesis
granulocytes in Arabic: خلية بيضاء محببة
granulocytes in Czech: Granulocyt
granulocytes in Danish: Granulocyt
granulocytes in German: Granulozyt
granulocytes in Spanish: Granulocito
granulocytes in Esperanto: Granulocito
granulocytes in French: Granulocyte
granulocytes in Italian: Granulocita
granulocytes in Hebrew: גרנולוציט
granulocytes in Dutch: Granulocyt
granulocytes in Norwegian: Granulocytter
granulocytes in Polish: Granulocyt
granulocytes in Portuguese: Agranulócito
granulocytes in Russian: Гранулоциты
granulocytes in Albanian: Granulociti
granulocytes in Slovak: Granulocyt
granulocytes in Serbian: гранулоцит
granulocytes in Finnish: Granulosyytti
granulocytes in Swedish: Granulocyt
granulocytes in Turkish: Granülosit