Trophic hormone
Encyclopedia
Tropic hormones are hormone
Hormone
A hormone is a chemical released by a cell or a gland in one part of the body that sends out messages that affect cells in other parts of the organism. Only a small amount of hormone is required to alter cell metabolism. In essence, it is a chemical messenger that transports a signal from one...

s that have other endocrine glands as their target. Most tropic hormones are produced and secreted by the anterior pituitary
Anterior pituitary
A major organ of the endocrine system, the anterior pituitary, also called the adenohypophysis, is the glandular, anterior lobe of the pituitary gland...

. The hypothalamus
Hypothalamus
The Hypothalamus is a portion of the brain that contains a number of small nuclei with a variety of functions...

 secretes tropic hormones that target the anterior pituitary, and the thyroid gland secretes thyroxine
Thyroxine
Thyroxine, or 3,5,3',5'-tetraiodothyronine , a form of thyroid hormones, is the major hormone secreted by the follicular cells of the thyroid gland.-Synthesis and regulation:...

, which targets the hypothalamus
Hypothalamus
The Hypothalamus is a portion of the brain that contains a number of small nuclei with a variety of functions...

 and therefore can be considered a tropic hormone.

Tropic hormones from the anterior pituitary include:
  • Thyroid-stimulating hormone
    Thyroid-stimulating hormone
    Thyrotrophin-stimulating hormone is a peptide hormone synthesized and secreted by thyrotrope cells in the anterior pituitary gland, which regulates the endocrine function of the thyroid gland.- Physiology :...

     (TSH or thyrotropin) – stimulates the thyroid gland to make and release thyroid hormone
    Thyroid hormone
    The thyroid hormones, thyroxine and triiodothyronine , are tyrosine-based hormones produced by the thyroid gland primarily responsible for regulation of metabolism. An important component in the synthesis of thyroid hormones is iodine. The major form of thyroid hormone in the blood is thyroxine ,...

    .
  • Adrenocorticotropic hormone
    Adrenocorticotropic hormone
    Adrenocorticotropic hormone , also known as 'corticotropin', 'Adrenocorticotrophic hormone', is a polypeptide tropic hormone produced and secreted by the anterior pituitary gland. It is an important component of the hypothalamic-pituitary-adrenal axis and is often produced in response to biological...

     (ACTH or corticotropin) – stimulates the adrenal cortex
    Adrenal cortex
    Situated along the perimeter of the adrenal gland, the adrenal cortex mediates the stress response through the production of mineralocorticoids and glucocorticoids, including aldosterone and cortisol respectively. It is also a secondary site of androgen synthesis.-Layers:Notably, the reticularis in...

     to release glucocorticoid
    Glucocorticoid
    Glucocorticoids are a class of steroid hormones that bind to the glucocorticoid receptor , which is present in almost every vertebrate animal cell...

    s.
  • Luteinizing hormone
    Luteinizing hormone
    Luteinizing hormone is a hormone produced by the anterior pituitary gland. In females, an acute rise of LH called the LH surge triggers ovulation and development of the corpus luteum. In males, where LH had also been called interstitial cell-stimulating hormone , it stimulates Leydig cell...

     (LH) – stimulates the release of steroid hormone
    Steroid hormone
    A steroid hormone is a steroid that acts as a hormone. Steroid hormones can be grouped into five groups by the receptors to which they bind: glucocorticoids, mineralocorticoids, androgens, estrogens, and progestogens...

    s in gonad
    Gonad
    The gonad is the organ that makes gametes. The gonads in males are the testes and the gonads in females are the ovaries. The product, gametes, are haploid germ cells. For example, spermatozoon and egg cells are gametes...

    s—the ovary
    Ovary
    The ovary is an ovum-producing reproductive organ, often found in pairs as part of the vertebrate female reproductive system. Ovaries in anatomically female individuals are analogous to testes in anatomically male individuals, in that they are both gonads and endocrine glands.-Human anatomy:Ovaries...

     and testes.
  • Follicle-stimulating hormone
    Follicle-stimulating hormone
    Follicle-stimulating hormone is a hormone found in humans and other animals. It is synthesized and secreted by gonadotrophs of the anterior pituitary gland. FSH regulates the development, growth, pubertal maturation, and reproductive processes of the body. FSH and Luteinizing hormone act...

     (FSH) – stimulates the maturation of eggs and production of sperm.
  • Growth hormone
    Growth hormone
    Growth hormone is a peptide hormone that stimulates growth, cell reproduction and regeneration in humans and other animals. Growth hormone is a 191-amino acid, single-chain polypeptide that is synthesized, stored, and secreted by the somatotroph cells within the lateral wings of the anterior...

     (GH)has both tropic and non-tropic effects. Growth hormone's major tropic effect is it releases insulin-like growth factor
    Insulin-like growth factor
    The insulin-like growth factors are proteins with high sequence similarity to insulin. IGFs are part of a complex system that cells use to communicate with their physiologic environment...

    s (IGFs) from the liver, which causes bone growth.


The hypothalamus
Hypothalamus
The Hypothalamus is a portion of the brain that contains a number of small nuclei with a variety of functions...

 controls the release of hormones from the anterior pituitary by secreting a class of hypothalamic neurohormone
Neurohormone
A neurohormone is any hormone produced and released by neurons.Examples include:*Thyrotropin-releasing hormone *Gonadotropin-releasing hormone *Adrenocorticotropin-releasing hormone*Oxytocin*Antidiuretic hormone *Epinephrine...

s called releasing and release-inhibiting hormones—which are released to the hypothalamo-hypophyseal portal system and act on the anterior pituitary.
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK