Coagulative necrosis


Coagulative necrosis

Coagulative necrosis is a type of accidental cell death typically caused by ischemia or infarction.

It is characterised by the 'ghostly' appearance of cells under light microscopy in the affected area of tissue. In coagulative necrosis the architecture of dead tissue is preserved for at least a couple days.[1] It is believed that the injury denatures structural proteins as well as lysosomal enzymes thus blocking the proteolysis of the damaged cells. The lack of lysosomal enzymes allows it to maintain a "coagulated" morphology for some time. Like most types of necrosis if enough viable cells are present around the affected area regeneration can occur.

Contents

Causes

Coagulative necrosis is most commonly caused by hypoxic conditions that do not involve severe trauma, toxins or an acute or chronic immune response. The lack of oxygen causes cell death in a localised area which is perfused by blood vessels failing to deliver primarily oxygen, but also other important nutrients. It is important to note that while ischemia in most tissues of the body will cause coagulative necrosis, in the central nervous system ischemia causes liquefactive necrosis as there is very little structural framework in neural tissue.

Pathology

Macroscopic

The macroscopic appearance of an area of coagulative necrosis is a pale segment of tissue contrasting against surrounding well vascularised tissue and is dry on cut surface. The tissue may later turn red due to inflammatory response. The surrounding surviving cells can aid in regeneration of the affected tissue unless they are stable or permanent.


Microscopic

The microscopic anatomy shows a lighter staining tissue (when stained with H&E) containing no nuclei with very little structural damage giving the appearance often quoted as 'ghost cells'. The decreased staining is due to digested nuclei which no longer show up as dark purple when stained with hematoxylin and removed cytoplasmic structures giving reduced amounts of intracellular protein reducing the usual dark pink staining cytoplasm with eosin.

Regeneration

As the majority of the structural remnants of the necrotic tissue remains, labile cells adjacent to the affected tissue will replicate and replace the cells which have been killed during the event. Labile cells are constantly undergoing mitosis and can therefore help reform the tissue, whereas nearby stable and permanent cells (e.g. neurons and cardiomyocytes) do not undergo mitosis and will not replace the tissue affected. Fibroblasts will also migrate to the affected area depositing fibrous tissue producing fibrosis or scarring in areas where viable cells do not replicate and replace tissue.

References

  1. ^ Robbins and Cotran: Pathologic Basis of Disease, 8th Ed. 2010. Pg. 15

External links


Wikimedia Foundation. 2010.

Look at other dictionaries:

  • Necrosis — For the film, see Necrosis (film). Necrotic leg wound caused by a brown recluse spider bite Necrosis (from the Greek νεκρός, dead , νέκρωσις, death, the stage of dying, the act of killing ) is the premature death of …   Wikipedia

  • necrosis — mortification; n. the death of some or all of the cells in an organ or tissue, caused by disease, physical or chemical injury, or interference with the blood supply (see gangrene). Caseous necrosis occurs in pulmonary tuberculosis, the lung… …   The new mediacal dictionary

  • necrosis — Pathologic death of one or more cells, or of a portion of tissue or organ, resulting from irreversible damage; earliest irreversible changes are mitochondrial, consisting of swelling and granular calcium deposits seen by …   Medical dictionary

  • coagulation necrosis — coagulative necrosis necrosis in which tissue becomes a dry, opaque, eosinophilic mass containing the outlines of anucleated cells, resulting from the denaturation of proteins following hypoxic injury, such as that caused by ischemia in… …   Medical dictionary

  • Liquefactive necrosis — (or colliquative necrosis) is a type of necrosis which results in a transformation of the tissue into a liquid viscous mass.[1] Often it is associated with focal bacterial or fungal infections. In liquefactive necrosis, the affected cell is… …   Wikipedia

  • Caseous necrosis — describes a form of biological tissue death, caseous meaning it has a cheese like appearance. The dead tissue appears as a soft and white proteinaceous dead cell mass. In caseous necrosis no histological architecture is preserved. On microscopic… …   Wikipedia

  • Gangrene — For the American football team nicknamed Gang Green , see New York Jets. Gangrene Classification and external resources Dry gangrene of the 1st to 4th toes of the right foot in a man with diabetes. ICD …   Wikipedia

  • death — /deth/, n. 1. the act of dying; the end of life; the total and permanent cessation of all the vital functions of an organism. Cf. brain death. 2. an instance of this: a death in the family; letters published after his death. 3. the state of being …   Universalium

  • ExAblate — The ExAblate (also known as ExAblate 2000) is a non invasive medical device manufactured by InSightec, a company based in Haifa, Israel with its US office in Dallas, TX. The ExAblate uses MRI guided Focused Ultrasound Surgery (MRgFUS) technology …   Wikipedia

  • Inflammation — Toes inflamed by Chilblains Inflammation (Latin, īnflammō, “I ignite, set alight”) is part of the complex biological response of vascular tissues to harmful stimuli, such as pathogens, damaged cells, or irritants …   Wikipedia


Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.