Pigments

Pigments (Exogenous & Endogenous)

Substances that have innate color, render artificial staining, unnecessary for normal tissue and are found in different tissues are known as pigments.

Classification

1.      Exogenous (formed outside the body)

Ø  Carbon

Ø  Dusts

Ø  Metals

Ø  Tattoos

Ø  Kaolin

Ø  Carotenoids

1.      Endogenous (formed inside the body)

i)       Phenolic pigments

ii)    Hematogenous pigments

Ø  Hemoglobins

Ø  Hematins

Ø  Parasitic pigments

Ø  Hemosiderins

Ø  Bile pigments

Ø  Porphyrins (photosensitizing pigments)

iii)   Lipogenic pigments

Ø  Tissue lipofuscins

Ø  Ceroid

Ø  Vitamin-E deficiency pigments

iv)  Miscellaneous pigments

Ø  Ochronosis pigments

Ø  Dubin-Johnson pigment

Ø  Cloissone kidney