Merck Manual

Please confirm that you are a health care professional

Overview of Major Chemical Classes of Hormones

Overview of Major Chemical Classes of Hormones

Hormone type

How they are made

Amount stored in endocrine cells

Mechanism of action

Identical structure between species?

Examples

Protein/polypeptide

Gene transcription/translation

High

Cell surface receptor

Variable; some yes, some no

ACTH, insulin

Steroid

Conversion from cholesterol

Low

Intracellular receptors

Yes

Estrogen, cortisol

Modified amino acids

Modification of 1 or 2 amino acids (tyrosine)

High

Moderate

Intracellular receptors

Cell surface receptors

Yes

Yes

Thyroxine

Catecholamines