Endocrinology and Hormones

Hypothalamus

The hypothalamus is found in the brain, just above the pituitary gland.  It serves as the link between the endocrine system and the nervous system by communicating with the pituitary gland. It controls the pituitary gland by increasing or decreasing the release of hormones.

Pituitary gland

The pituitary is a very small organ just below the hypothalamus. Although small, it has a large effect on the rest of the endocrine system.  it releases hormones that help regulate the function of most of the other endocrine glands such as the thyroid, adrenals and reproductive glands. It also produces hormones that stimulate bone growth, effects puberty and sexual development, excretes a hormone that acts on the kidneys among other actions.

Pineal body (pineal gland)

Also in the center of the brain, the pineal gland secretes melatonin. Melatonin is released in a rhythmic cycle; it’s higher at night and helps regulate the sleep/wake cycle. Research also shows that melatonin has an immune supporting effect among other things.

Thyroid gland

The thyroid is a butterfly shaped gland found at the front of your neck. It makes and secretes two thyroid hormones, T3 and T4. These hormones help regulate metabolism, blood pressure, body temperature, heart rate, hair and body growth among other things.

The thyroid gland also produces calcitonin, which opposes the effects of PTH and acts to lower blood calcium levels. Calcitonin lowers blood calcium level by increasing the amount of calcium excreted in the urine and decreasing the break down of bone. It is in a delicate balance with parathyroid hormone.

Parathyroid glands

Parathyroid gland are tiny glands that are found in the thyroid gland. There are four of these, one in each quadrant of the thyroid.. Parathyroid glands control the calcium levels in our blood, in our bones and throughout our body. Parathyroid glands regulate the calcium by producing a hormone called parathyroid hormone (PTH) that can be involved with things like absorption of calcium from the diet or leeching it from your bones. Calcium is critical to maintain in a delicate balance in the body.

Pancreas

Located in the abdomen, the pancreas produces two main hormones that balance blood sugar, insulin (which decreases blood sugar) and glucagon (which increases blood sugar). The pancreas has double duty in that it is not only an endocrine organ but is an exocrine organ and releases digestive enzymes into the intestines so that the food you eat gets digested enough to have the nutrients absorbed.

Adrenal glands

The adrenal glands secrete/release 3 major hormone groups: mineralocorticoids (predominantly aldosterone which effects your blood pressure among other things), glucocorticoids (predominantly cortisol), and androgens (predominantly testosterone and dehydroepiandrosterone).  The ‘adrenaline’ you feel when under stress is due to hormones released by the adrenal glands and their effect on the rest of your body.

Ovaries

The ovaries are the female sex glands. Their functions are to produce eggs for reproduction and the hormones they produce and excrete are estrogens and progesterone.

Testes

The testes are the testicles or male sex glands. The functions are to produce sperm for reproduction and the hormones the produce are testosterone.

Adipose tissue (fat cells) – white, brown and beige adipocytes. 

They play a role in glucose (sugar) and lipid (fats) metabolism, and they also release endocrine factors that regulate energy expenditure, appetite, blood sugar balance, insulin sensitivity to allow glucose into cells, inflammation and tissue repair and probably a number of other things.