Coagulative Necrosis + Morphology

- Coagulative Necrosis / summarized

- Description of the GROSS appearance of Coagulative necrosis.

- Description of the MICROSCOPIC appearance of Coagulative necrosis.

1. features of coagulative necrosis

2. coagulative necrosis Is a type of cell death typically caused by  Hypoxia  or  infarction . It is believed that the injury denatures * structural proteins as well as lysosomal enzymes * thus blocking  the proteolysis * of the damaged cells. In coagulative necrosis the architecture of dead tissue is  preserved  for at least a couple of days.

3. coagulative necrosis Commonly affected organs: Heart * , Kidney, Liver, and Spleen. The lack of lysosomal enzymes allows it to maintain a " coagulated " morphology for some time.

4. The appearance of an area of coagulative necrosis is a pale segment of tissue /contrasting against surrounding well vascularized tissue and is dry on cut surface. The tissue may later turn red due to inflammatory response. Gross Features (Spleen) Two large infarctions (wedge shaped)

5. Gross Features (Spleen) Two large infarctions (wedge shaped) The necrosis area is :   Swollen , Firm   ,  & Pale – With progression, they become more yellowish, softer, and shrunken.

6. ↓ Outline ( Kidney ) NO  cell organelles are seen. Tissues Cells

7. kidney Liver Heart Kidney

8. Many nuclei have become pyknotic (shrunken and  dark ) and have then undergone karorrhexis (fragmentation) and karyolysis (dissolution). Microscopic Features The microscopic appearance is a mess because so many cells have died that the tissue is not recognizable . * The cytoplasm and cell borders are not recognizable.

9. #Marked by: 1- loss of nuclei 2-cell outlines are visible but  NO  cell organelles are seen. (Heart) patient with myocardial infarction.

10. Kidney Heart Spleen Liver

11. THANK YOU

12. REFERENCES Robbins and Cotran: Pathologic Basis of Disease, 8th Ed. 2010. Pg. 15 NECROSIS (online project)   https://cellbiology.med.unsw.edu.au/cellbiology/index.php/2009_Group_8_Project Luke CJ, Pak SC, Askew YS, Naviglia TL, Askew DJ, Nobar SM, Vetica AC, Long OS, Watkins SC, Stolz DB, Barstead RJ, Moulder GL, Brömme D, Silverman GA. An intracellular serpin regulates necrosis by inhibiting the induction and sequelae of lysosomal injury; Cell 2007 130(6):1108-19  [PubMed]