anatomy 20.3 pt 2

Major hormones secreted by anterior pituitary

Seven major hormones.

Number of tropic hormones from anterior pituitary

Five.

Hormone secreted by thyrotropic cells

Thyroid-stimulating hormone (TSH), also called thyrotropin.

Location of thyrotropic cells

In the pars distalis of the anterior pituitary.

Function of TSH

Regulates the release of thyroid hormone from the thyroid gland.

Conditions increasing TSH secretion

Pregnancy, stress, and exposure to low temperatures.

Hormones secreted by gonadotropic cells

Follicle-stimulating hormone (FSH) and luteinizing hormone (LH).

Collective name for FSH and LH

Gonadotropins.

Location of gonadotropic cells

In the pars distalis of the anterior pituitary.

Regulation by FSH and LH

Influence reproductive system activities by regulating hormone synthesis by the gonads and the production and maturation of gametes.

Hormone secreted by corticotropic cells

Adrenocorticotropic hormone (ACTH), also called corticotropin.

Location of corticotropic cells

In the pars distalis of the anterior pituitary.

Function of ACTH

Stimulates the adrenal cortex to produce and secrete its hormones.

Hormone secreted by somatotropic cells

Growth hormone (GH), also called somatotropin.

Location of somatotropic cells

In the pars distalis of the anterior pituitary.

Direct effect of growth hormone

Stimulates cell growth and cell division (mitosis).

Body systems affected by growth hormone

The skeletal and muscular systems.

Growth hormone as a tropic hormone

Stimulates the liver to produce insulin-like growth factor 1 and 2 (IGF-1 and IGF-2).

Another name for IGF-1 and IGF-2

Somatomedin.

Function of somatomedin

Stimulates growth at the epiphyseal plates of long bones.

Two anterior pituitary hormones not considered tropic hormones

Prolactin (PRL) and melanocyte-stimulating hormone (MSH).

Why prolactin and MSH are not tropic hormones

They do not stimulate hormone secretion by other endocrine tissues or glands; they directly affect specific cells or activities.

Hormone secreted by mammotropic cells

Prolactin (PRL).

Location of mammotropic cells

In the pars distalis of the anterior pituitary.

Function of prolactin

Regulates mammary gland growth and breast milk production, beginning during pregnancy.

Cells that secrete prolactin

Mammotropic cells.

Hormone secreted by cells in the pars intermedia

Melanocyte-stimulating hormone (MSH).

Function of MSH

Stimulates the rate of melanin synthesis by melanocytes and the distribution of melanocytes in the skin.

FLAT PIG mnemonic

Used to remember the primary anterior pituitary hormones: FSH, LH, ACTH, TSH, Prolactin, and GH; the I in PIG is ignored.

Consequences of growth hormone deficiency

Results in pituitary dwarfism due to inadequate GH production, causing growth retardation.

Excessive GH effects in children

Causes pituitary gigantism before epiphyseal plates close.

Excessive GH effects in adults

Causes acromegaly.