, also known as interstitial cells of Leydig
, are found adjacent to the seminiferous tubules
in the testicle
. They can secrete testosterone
and are often closely related to nerves. Leydig cells have round vesicular nuclei
and a granular eosinophilic cytoplasm
Leydig cells are named after the German anatomist Franz Leydig
, who discovered them in 1850
Leydig cells release a class of hormones
). They secrete testosterone
(DHEA), when stimulated by the pituitary
hormone luteinizing hormone
(LH). LH increases cholesterol desmolase
activity (an enzyme associated with the conversion of cholesterol
), leading to testosterone synthesis secretion by Leydig cells.
Follicle-stimulating hormone (FSH) increases the response of Leydig cells to LH by increasing the number of LH receptors expressed on Leydig cells.
Leydig cells are polygonal, eosinophilic cells with a round vesicular nucleus and contain lipid
droplets. They contain abundant smooth endoplasmic reticulum
, which accounts for their eosinophilia. Frequently, lipofuscin
pigment and rod-shaped crystal-like structures (Reinke's crystals
) are found.
Leydig cells form during the 16th and 20th week of gestation
and are quiescent until puberty