Week 5 - Endocrine System

Normal Blood Sugar

70-100 mg/dL

Hypothyroidism

A disorder caused by a thyroid gland that is slower and less productive than normal. Can cause weight gain, chills and a lack of energy.

Insulin

A hormone produced by the pancreas or taken as a medication by many diabetics. Regulates blood sugar levels by facilitating the uptake of glucose into tissues.

Glucagon

A hormone produced by the pancreas that raises blood glucose levels; an antagonistic hormone to insulin. Tells the liver to convert glycogen back into glucose.

Renin

A hormone secreted by the kidney; it raises blood pressure by influencing vasoconstriction (narrowing of blood vessels).

Cortisol

A stress hormone released by the adrenal cortex. Associated with the metabolism. But when someone undergoes continuous chronic stress, the cortisol levels get out of whack.

When blood pressure is too low

Aldosterone is release, this hormone promotes the retention of sodium by the kidneys and the release of potassium from the kidneys. Sodium retention encourages water retention, which helps the blood pressure and blood volume increase.

When potassium levels are too high in the kidneys

Aldosterone is released, which helps the blood pressure AND also tells the kidneys to release potassium.

Anterior Pituitary Gland

Also known as the adenohypophysis. It produces & secretes 6 hormones (FSH, LH, ACTH, TSH, prolactin, and growth hormone) Cells bodies of the neurons are located in the hypothalamus. The axons of these shared neurons are shorter and these axons are connected to capillary beds that are located closer the hypothalamus. These capillary beds come back together into a blood vessel, then breaks up into capillary beds again and exits the pituitary gland.

Posterior Pituitary Gland

Also known as the neurohypophysis. It stores & secretes 2 hormones (oxytocin and ADH). Cells bodies of the neurons are located in the hypothalamus. The axons of these shared neurons are long enough to stretch to the posterior pituitary gland from the hypothalamus. Contains capillary beds near the axon terminals to help supply nutrients & oxygen from the blood to the tissue, also helps adsorb waste products (CO2) from the tissue to the blood.

Giantism

An abnormal condition characterized by excessive growth of the body from hypersecretion of growth hormone as a child.

Pituitary Dwarfism

An abnormally short height caused by undersecretion of growth hormone from the pituitary gland.

Thyroid Gland

An endocrine gland that surrounds the trachea in the neck and its main jobs are regulating the metabolism, energy consumption of the cells, cells division, body heat, bone growth. Is stimulated by the Thyroid Stimulating Hormone (TSH) that is produced by the Anterior Pituitary Gland.

Hypophyseal Portal System

Blood leaving a capillary bed in hypothalamus travels to to another capillary bed in anterior pituitary, which eventually exits the pituitary gland.

Lypolysis

Breakdown of triglycerides (fat) for energy. Type 1 diabetics relay on this method of obtaining energy. However the results of a metabolism relying on strictly just lipolysis to obtain glucose is; high ketone levels in the metabolism causing the pH of blood to become more acidic.

Low Blood Sugar

Can occur if a person with diabetes has not eaten or is vomiting or has injected too much insulin. The cells don't have access to sugar and can't produce ATP.

Type 2 diabetes

Diabetes of a form that develops especially in adults and most often obese individuals and that is characterized by the overproduction of insulin due to poor diet and lack of exercise. Diet consists of a lot of sugars, which causes the overproduction of insulin to the point where the cells become resistant to the insulin.

Type 1 diabetes

Diabetes of a form that usually develops during childhood or adolescence and is characterized by a severe deficiency of insulin, leading to high blood glucose levels. Similar to an autoimmune disease, in which the immune system attacks insulin producing cells (pancreatic beta cells) which causes the production of insulin to stop, so the cells never get the signal from insulin to open their protein channels to allow glucose to diffuse in.

Neurons in the Pituitary Gland

Doesn't produce neurotransmitters, but instead produced hormones. These hormones travel down the axons of these neurons within the hypothalamus & the pituitary gland, eventually these hormones reach the capillary beds and enter the blood.

Hyperthyroidism

Excessive activity of the thyroid gland produces abnormally high levels of thyroid hormone. Can lead to graves disease.

Gluconeogenesis

Formation of glucose from noncarbohydrate sources such as fats & proteins. This process occures when your liver runs out of glycogen.

Parathyroid Glands

Four small pea-like organs located on the posterior side of the thyroid gland that regulates calcium and phosphate balance in blood, bones, and other tissues. Releases PTH (parathyroid hormone).

Ketones

Fragments formed by the tissues during incomplete use of fat for energy, and released into the blood.

High Blood Sugar

High levels of sugar in our blood can be harmful to our capillaries and causes our blood vessels to fall apart.

Tropic Hormones of Anterior Pituitary

Hormones that stimulate other glands to release their hormones.

When the blood sugar increases

Insulin binds to cells and tells those cells to open their protein channels so glucose can diffuse into the cell. Can also tell the liver to covert extra blood glucose into glycogen, evidently also regulating the blood sugar levels.

Chronic Stress

Long term stress that will cause larger amounts of ACTH (Adrenocorticotropic Hormone) to be released, higher levels of ACTH will cause the aldosterone hormone to increase as well and evidently increasing blood pressure. This will also increase cortisol levels. Higher levels of cortisol will encourage ATP production, higher amounts of fatty acids, glucose and amino acids in the blood. These increased levels of cortisol will also encourage breakdown of proteins, glycogenesis, lipolysis and suppresses the immune system.

Capillary Beds

Networks of very small blood vessels in tissue or an organ, also where chemical exchange takes place between the blood and the organ/tissue.

When calcium levels are low

PTH is produced from the Parathyroid glands and causes reabsorption of calcium in the kidneys, stimulated vitamin D synthesis (which helps absorb calcium from our food) and finally causes the osteoclasts to break down bones to increase calcium in the blood.

Prolactin

Produced by the Anterior Pituitary Gland. Important hormone involved in the production of breast milk in women.

LH (Luteinizing Hormone)

Produced by the Anterior Pituitary Gland. Important hormone that causes the secretion of sex hormones by the testes and ovaries. A tropic hormone. Relies on a negative feedback loop.

FSH (Follicle Stimulating Hormone)

Produced by the Anterior Pituitary Gland. Important hormone that influences the maturing of eggs and production of sperm. A tropic hormone. Relies on a negative feedback loop.

ACTH (Adrenocorticotropic Hormone)

Produced by the Anterior Pituitary Gland. Important hormone that stimulates secretion of hormones by adrenal cortex.

TSH (Thyroid Stimulating Hormone)

Produced by the Anterior Pituitary Gland. Important hormone that stimulates thyroid gland and the secretion of the thyroid hormone.

Growth Hormone

Produced by the Anterior Pituitary Gland. Stimulates the growth of skeletal muscles and bones. Also helps conserve glucose in the blood. Works against insulin.

Oxyotocin

Produced by the Posterior Pituitary Gland. Important hormone involved in child labor, produces contractions. Starts a positive feedback loop. Helps with the ejection of breast milk in women to make it easier to feed a baby.

ADH (Antidiuretic Hormone)

Produced by the Posterior Pituitary Gland. Important hormone involved in urine production and the kidneys. Tells the kidneys to produce a small amount of concentrated urine and hold onto body fluids. Released when you are dehydrated, when you're dehydrated the hypothalamus recognizes the low blood volume, low blood pressure & higher concentration of salt in blood.

Pancreas Exocrine Function

Produces digestive enzymes.

Pancreas Endocrine Function

Produces insulin and glucagon to regulate blood sugar levels.

Adernal Cortex

Releases cortisol & aldosterone.

Adernal Medulla

Releases norepinephrine & epinephrine (AKA adrenaline - Stress Hormones). Associated with the sympathetic nervous system.

Glycogen

Storage form of glucose which is produced by the liver.

Aldosterone

The "salt-retaining hormone" which promotes the retention of sodium by the kidneys and the release of potassium from the kidneys. Sodium retention promotes water retention, which promotes a higher blood volume and pressure. This hormone is released when the blood pressure is too low and/or when the potassium levels are too high.

Acromegaly

The abnormal enlargement of the extremities caused by intaking artificial growth hormones as an adult. These artificial hormones allow muscle growth, but also tells the bones to growth even though they are fully calcified.

When blood pressure is too high

The heart releases the hormone AMP, AMP inhibits the release of aldosterone from the adernal cortex.

Pituitary Gland

The master gland of the endocrine system. Extends downwards from the hypothalamus. Cells bodies of the neurons that the pituitary gland & the hypothalamus share are located in the hypothalamus. Is a neuro-endocrine gland.

Adernal Gland

The tissue located on top of the kidneys that releases adrenaline and cortisol during states of emotional arousal.

Epithelial Cells in Anterior Pituitary Gland

These special cells are located in the walls of the capillaries within the pituitary gland. These cells act as receptors and when connected to certain hormones released by the hypothalamus; these epithelial cells release their own set of hormones.

Radioactive Iodine Uptake

Treatment for thyroid cancer, which selectively kills the thyroid tissue and hormone replacement therapy is needed after this treatment.

Neuro-endocrine

Utilizes both the nervous system and true endocrine glands. Contains neurons that produces hormones instead of neurotransmitters.

Thyroid cancer

When the thyroid gland tries to produce TSH, but cant complete this process without iodine, this evidently causes pieces of unfinished TSH to become backed up in the thyroid gland. The successful recovery rate from thyroid cancer is high because the treatment for Thyroid cancer is radioactive iodine.

When the blood sugar decreases

When you begin to feel hungry. The pancreas releases glucagon.

Blood becoming more basic

can cause the nervous system to become overstimulated and hyperactive.

Blood becoming more acidic

can cause the nervous system to shut down.

Hyperglycemia

high blood sugar levels.

Hypoglycemia

low blood sugar levels.