What is "trophic hormone"

n. A hormone that acts upon non-endocrine organs and tissues for the purposes of promoting cellular growth, differentiation, and survival. Often confused with tropic hormones.

Trophic hormone is a hormone that has a growth effect, hyperplasia or hypertrophy, on the tissue it is stimulating. The term trophic is from Ancient Greek τροφικός (trophikós) meaning "pertaining to food or nourishment", here used to mean "growth"; this is the same origin as atrophy. This should not be confused with tropic, as in the similar-sounding tropic hormone – the words and concepts are both unrelated.

A key example of this is thyroid-stimulating hormone stimulating the thyroid; excess thyroid-stimulating hormone can create a goitre.

Trophic hormones from the anterior pituitary include:

• Thyroid-stimulating hormone (TSH or thyrotropin) – stimulates the thyroid gland increasing the size and number of cells.
• Adrenocorticotropic hormone (ACTH or corticotropin) – stimulates the adrenal cortex increasing the size and number of cells.

Gastrin is a trophic hormone that causes hyperplasia of enterochromaffin cells which may transform into carcinoid tumors.