Tropic hormone

The term tropic is from Ancient Greek τροπικός (tropikós), in the sense "of or pertaining to a turn or change", meaning "causing a change, affecting"; this is the same origin as tropic and trope. This should not be confused with trophic, as in similar-sounding trophic hormone – the words and concepts are both unrelated. Tropic hormones are contrasted with non-tropic hormones, which directly stimulate target cells.

Examples

Anterior pituitary

Tropic hormones from the anterior pituitary include:

• Thyroid-stimulating hormone (TSH or thyrotropin) – stimulates the thyroid gland to make and release thyroid hormone.
• Adrenocorticotropic hormone (ACTH or corticotropin) – stimulates the adrenal cortex to release glucocorticoids.
• Luteinizing hormone (LH) – stimulates the release of steroid hormones in gonads—the ovary and testes.
• Follicle-stimulating hormone (FSH) – stimulates the maturation of eggs and production of sperm.

Hypothalamus

In turn, the hypothalamus controls the release of hormones from the anterior pituitary by secreting a class of hypothalamic neurohormones called releasing and release-inhibiting hormones—which are released to the hypothalamo-hypophyseal portal system and act on the anterior pituitary.