histopath Flashcards
Preserve tissues permanently in as life-like a state as possible
Fixation
five major groups of fixatives
Aldehydes
Mercurials
Alcohols
Oxidizing agent
Picrates
Aldehydes include
Formaldehyde (formalin)
Glutaraldehyde
Tissue is fixed by cross linkages formed in the proteins, particularly between Lysine residues
Aldehydes
is good for immunohistochemical techniques
Formaldehyde
The standard solution for aldehyde
10% neutral buffered formalin
Causes deformation of alpha-helix structure in proteins so is not good for immunohistochemical staining
Glutaraldehyde
is good for electron microscopy
Glutaraldehyde
The standard solution for glutaraldehyde
2% buffered glutaraldehyde
Fix tissue by an unknown mechanism
Mercurials
for fixation of hematopoietic and reticuloendothelial tissues
Mercurials
Mercurial contains
mercuric chloride
B-5
Zenker’s
Alcohols contains
Methyl alcohol (methanol)
Ethyl alcohol (ethanol)
Protein denaturants and are not used routinely for tissues because they cause too much brittleness and hardness
Alcohols
very good for cytologic smears because they act quickly and give good nuclear detail
Alcohol