Dehydroepiandrosterone (DHEA)
DHEA is a steroid precursor of androgens and estrogens.
- functions
- regulation of expression
- consequences of overexpression
- consequences of underexpression
- signalling pathways
- structure
Function
DHEA is produced in small amounts by the adrenal cortex (zona reticularis). In males it has little effect due to the large amounts of testosterone present.
In females, DHEA is responsible for many of the same effects as testosterone, including enhancement of female pubertal growth, development of axillary and pubic hair, and development and maintenance of female sex drive.
Regulation of Expression
- cells that express:
- tissue distribution:
- temporal expression:
Consequences of Overexpression
Consequences of Underexpression
Adrenal insufficiency can cause pubic hair loss in females due to loss of DHEA production. Testosterone production by the testes spares men from prominent effects of DHEA loss.
Signalling Pathways
Both PRL and GH have similiar affinities for the PRL receptor.
Structure
Prolactin is a 199 amino acid hormone with 16% homology to growth hormone.