Endocrine System

Target cell/organs

. a tissue or organ on which a hormone exerts its action; generally, a tissue or organ with appropriate receptors for a hormone.

Calcitonin

Calcitonin is a naturally occurring hormone. It helps regulate calcium levels in your body and is involved in the process of bone building.

Epinephrine

a hormone secreted by the adrenal medulla upon stimulation by the central nervous system in response to stress, as anger or fear, and acting to increase heart rate, blood pressure, cardiac output, and carbohydrate metabolism.

Luteinizing hormone

a hormone secreted by the anterior pituitary gland that stimulates ovulation in females and the synthesis of androgen in males.

Melatonin

a hormone secreted by the pineal gland that inhibits melanin formation and is thought to be concerned with regulating the reproductive cycle.

adrenocorticotropic hormone

a hormone secreted by the pituitary gland and stimulating the adrenal cortex

Norepinephrine

a hormone that is released by the adrenal medulla and by the sympathetic nerves and functions as a neurotransmitter. It is also used as a drug to raise blood pressure.

Thyroid-stimulating

a hormone that is secreted by the anterior lobe of the pituitary gland and stimulates the thyroid gland —abbreviation TSH —called also thyrotropic hormone, thyrotropin.

Growth hormone

a hormone that stimulates growth in animal or plant cells, especially (in animals) a hormone secreted by the pituitary gland.

Thyroid gland

a large ductless gland in the neck that secretes hormones regulating growth and development through the rate of metabolism.

Pancreas

a large gland behind the stomach that secretes digestive enzymes into the duodenum. Embedded in the pancreas are the islets of Langerhans, which secrete into the blood the hormones insulin and glucagon.

Thymus gland

a lymphoid organ situated in the neck of vertebrates that produces T cells for the immune system. The human thymus becomes much smaller at the approach of puberty.

Pineal gland

a pea-sized conical mass of tissue behind the third ventricle of the brain, secreting a hormonelike substance in some mammals.

Positive feedback loop

a process that occurs in a feedback loop in which the effects of a small disturbance on a system include an increase in the magnitude of the perturbation.

Negative Feedback loop

a reaction that causes a decrease in function. It occurs in response to some kind of stimulus. Often it causes the output of a system to be lessened

Hypothalamus

a region of the forebrain below the thalamus that coordinates both the autonomic nervous system and the activity of the pituitary, controlling body temperature, thirst, hunger, and other homeostatic systems, and involved in sleep and emotional activity.

Progesterone

a steroid hormone released by the corpus luteum that stimulates the uterus to prepare for pregnancy.

Testosterone

a steroid hormone that stimulates development of male secondary sexual characteristics, produced mainly in the testes, but also in the ovaries and adrenal cortex.

Triiodothyronine

a thyroid hormone similar to thyroxine but having greater potency.

Corticosteroids

any of a group of steroid hormones produced in the adrenal cortex or made synthetically. There are two kinds: glucocorticoids and mineralocorticoids. They have various metabolic functions and some are used to treat inflammation.

Estrogen

any of a group of steroid hormones that promote the development and maintenance of female characteristics of the body. Such hormones are also produced artificially for use in oral contraceptives or to treat menopausal and menstrual disorders

Steroid based

any of a large group of fat-soluble organic compounds, as the sterols, bile acids, and sex hormones, most of which have specific physiological action.

Hormones

chemical messengers that are secreted directly into the blood, which carries them to organs and tissues of the body to exert their functions.

Endocrine gland

glands of the endocrine system that secrete their products, hormones, directly into the blood rather than through a duct. The major glands of the endocrine system include the pineal gland, pituitary gland, pancreas, ovaries, testes, thyroid gland, parathyroid gland, hypothalamus and adrenal glands.

Thyroxine (T4)

he main hormone produced by the thyroid gland, acting to increase metabolic rate and so regulating growth and development.

Gonadotropic hormone

hormone secreted by the anterior pituitary gland and placenta; stimulates the gonads and controls reproductive activity.

Antidiuretic hormone

hormone that helps your kidneys manage the amount of water in your body.

Aldosterone

steroid hormone, "the main mineralocorticoid hormone", produced by the outer section of the adrenal cortex in the adrenal gland.

Amino acid based

the building blocks of all biological proteins.MAde out of Amino acids.././

Pituitary gland

the major endocrine gland. A pea-sized body attached to the base of the brain, the pituitary is important in controlling growth and development and the functioning of the other endocrine glands.

Testes

the male gonad or reproductive gland, either of two oval glands located in the scrotum

Cortisol

these hormones are involved in the regulation of metabolism in the cells and they also help us regulate stress within the body. Cortisol is a steroid based hormone and is synthesized from cholesterol. Cortisol is made in the adrenal cortex of the adrenal gland (see diagram below).

Pancreatic islets

tiny clusters of cells scattered throughout the pancreas. Pancreatic islets contain several types of cells, including beta cells, that produce the hormone insulin.

Adrenal gland

Either of two small endocrine glands, one located above each kidney.

Oxytocin

a hormone released by the pituitary gland that causes increased contraction of the uterus during labor and stimulates the ejection of milk into the ducts of the breasts.

Thymosin

One of several polypeptide hormones secreted by the thymus that control the maturation of T cells. They are derived from a polypeptide called prothymosin-alpha (PTMA) or alpha thymosin.

Prolactin

a hormone released from the anterior pituitary gland that stimulates milk production after childbirth.

Parathyroid hormones

a hormone of the parathyroid gland that regulates the metabolism of calcium and phosphorus in the body—abbreviation PTH; called also parathormone

Adrenal cortex

The outer portion of the adrenal gland located on top of each kidney.

Cortisone

a hormone produced by the adrenal cortex. One of the glucocorticoids, it is also made synthetically for use as an anti-inflammatory and anti-allergy agent.

Insulin

a hormone produced in the pancreas by the islets of Langerhans that regulates the amount of glucose in the blood. The lack of insulin causes a form of diabetes.

Ovaries

a female reproductive organ in which ova or eggs are produced, present in humans and other vertebrates as a pair.

Exocrine gland

a gland (as a sweat gland, a salivary gland, or a kidney) that releases a secretion external to or at the surface of an organ by means of a canal or duct

follicle-stimulating hormone

a gonadotropin, a glycoprotein polypeptide hormone. FSH is synthesized and secreted by the gonadotropic cells of the anterior pituitary gland, and regulates the development, growth, pubertal maturation, and reproductive processes of the body.

Glucagon

a hormone formed in the pancreas that promotes the breakdown of glycogen to glucose in the liver.

Adrenal medulla

part of the adrenal gland. It is located at the center of the gland, being surrounded by the adrenal cortex.

Parathyroid gland

small endocrine glands in the neck of humans and other tetrapods that produce parathyroid hormone. Humans usually have four parathyroid glands, variably located on the back of the thyroid gland, although considerable variation exists.