Enzyme Histochemistry

What is the primary function of enzyme histochemistry?

What is the purpose of introducing a dye or marker compound in enzyme histochemistry?

What type of enzyme reaction uses diazonium salt as a color indicator?

What is the product of a dehydrogenase reaction in enzyme histochemistry?

What is the significance of enzyme histochemistry in conventional histology?

What is the purpose of embedding the tissue in a solution containing the substrate of the enzyme to be localized?

What is the role of tetranitrotetrazolium chloride blue (TNBT) in a dehydrogenase reaction?

What is the outcome of the reaction between the dye compound and the complex formed by the enzyme-substrate reaction?

Enzyme Histochemistry

Enzyme histochemistry is a morphological technique that highlights functional alterations in tissues.
It provides a link between biochemistry and morphology, and furnishes vital information for conventional histology, immunohistochemistry, and molecular pathology.

Steps in Enzyme Histochemistry

Embedding the tissue in a solution containing the substrate of the enzyme to be localized.
The enzyme acts on the substrate to form a complex.
Introduction of a dye or marker compound.
The reaction of the dye compound with the enzyme-substrate complex forms a colored insoluble product.
The product can be viewed under a light microscope and subjected to quantitative analysis.

Enzyme Histochemical Techniques

There are several enzyme histochemical techniques, including Succinic dehydrogenase, NADH diaphorase, Aminopeptidase, Acid phosphatase, and Alkaline phosphatase.
Dehydrogenase reactions use enzyme substrates like sodium succinate or sodium L-lactate, which are oxidized, and a stoichiometric color indicator tetranitrotetrazolium chloride blue (TNBT) is reduced to black or blue formazan.
The formazan binds to local protein, allowing precise localization of the enzyme dehydrogenase in a particular tissue compartment.
Diazonium salt is used as a color indicator in a second group of enzyme reactions, primarily for esterases and phosphatases.

Enzyme histochemistry links biochemistry and morphology, providing vital information for histology, immunohistochemistry, and molecular pathology. It involves biochemical analysis of enzyme activity and localization.