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Hormones

Definition: Chemical substances having a specific regulatory effect on the activity of a certain organ or organs. The term was originally applied to substances secreted by various ENDOCRINE GLANDS and transported in the bloodstream to the target organs. It is sometimes extended to include those substances that are not produced by the endocrine glands but that have similar effects.
Notes: GEN; prefer specifics; for hormone receptors, see note at RECEPTORS, CELL SURFACE

Hormones Categories.
Adrenal Cortex Hormones
Gastrointestinal Hormones - HORMONES secreted by the gastrointestinal mucosa that affect the timing or the quality of secretion of digestive enzymes, and regulate the motor activity of the digestive system organs.
Gonadal Hormones - Hormones produced by the GONADS, including both steroid and peptide hormones. The major steroid hormones include ESTRADIOL and PROGESTERONE from the OVARY, and TESTOSTERONE from the TESTIS. The major peptide hormones include ACTIVINS and INHIBINS.
Gonadotropins - Hormones that stimulate gonadal functions such as GAMETOGENESIS and sex steroid hormone production in the OVARY and the TESTIS. Major gonadotropins are glycoproteins produced primarily by the adenohypophysis (GONADOTROPINS, PITUITARY) and the placenta (CHORIONIC GONADOTROPIN). In some species, pituitary PROLACTIN and PLACENTAL LACTOGEN exert some luteotropic activities.
Hormones, Ectopic - Hormones released from neoplasms or from other cells that are not the usual sources of hormones.
Hypothalamic Hormones - Hormones isolated from the hypothalamus which exercise control over other organs, primarily the pituitary gland. Well-known members include certain pituitary hormone-releasing hormones and pituitary hormone release inhibiting hormones. Vasopressin and oxytocin which are found in the posterior pituitary may also be secreted by the hypothalamus but are not grouped here (PITUITARY HORMONES, POSTERIOR).
Invertebrate Hormones - Hormones produced by invertebrates, usually insects, mollusks, annelids, and helminths.
Pancreatic Hormones - Peptide hormones secreted into the blood by cells in the ISLETS OF LANGERHANS of the pancreas. The alpha cells secrete glucagon; the beta cells secrete insulin; the delta cells secrete somatostatin; and the PP cells secrete pancreatic polypeptide.
Peptide Hormones - Hormones synthesized from amino acids. They are distinguished from INTERCELLULAR SIGNALLING PEPTIDES AND PROTEINS in that their actions are systemic.
Thymus Hormones - Humoral factors secreted by the thymus gland. They participate in the development of the lymphoid system and the maturation of the cellular immune response.
Thyroid Hormones - Hormones secreted by the thyroid gland.

Hormones Definitions and Terms

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