Endocrine System Flashcards
Antagonistic
Acting in opposition; mutually opposing
Electrolyte
Mineral salt (sodium, potassium, calcium) that carries an electrical charge in solution
Glucagon
Hormone produced by pancreatic alpha cells that stimulates the liver to change stored glycogen (a starch form of sugar) to glucose.
Glucose
Simple sugar that is the end product of carbohydrate digestion
Insulin
Hormone produced by pancreatic beta cells that allows body cells to use glucose for energy or store it in the liver as glycogen
Sympathomimetic
Agent that mimics the effects of the sympathetic nervous system
Pituitary Gland (hypophysis)
Is a pea sized organ located at the base of the brain.
It’s known as the MASTER GLAND because it regulates many body activities and stimulates other glands to secrete (produce) their own specific hormones.
Adenohypophysis
Anterior lobe of the pituitary gland
Produces at least 6 hormones.
Neurohypophysis
Posterior lobe of the pituitary gland.
Stores and secretes two hormones produced by the hypothalamus:
- Antidiuretic hormone (ADH)
Abnormal variations makes it more difficult for the body to removed water - Oxytocin
These hormones are released into the bloodstream
Thyroid gland
The largest gland of the endocrine system.
An H-shaped organ located in the neck just below the larynx, composed of two large lobes separated by a strip of tissue called an isthmus.
Thyroid hormone (TH)
Is the body’s major metabolic hormone
Increases the rate of oxygen consumption and rate at which carbohydrates, proteins, and fats are metabolized
Affects virtually every cell in the body
Influences growth hormone and plays and important role in maintaining blood pressure
Thyroxine (T4)
The major hormone secreted by the thyroid
Increases energy production from all food types
Increases rate of protein synthesis
Triiodothyronine (T3)
Formed at the target tissues by conversion of T4 to T3
Increases energy production from all food types
Increases rate of protein synthesis
Parathyroid glands
Consists of at least four separate glands located on the posterior surface of the lobes of the thyroid gland.
Produce parathyroid hormone (PTH)
Parathyroid hormone (PTH)
Helps to regulate calcium balance by stimulations three target organs: bones, kidneys, and intestines.
Calcium and phosphates are released from bones, increasing concentration of these substances in blood
Causes kidneys to conserve blood calcium and increase the excretion of phosphates in urine.
Adrenal glands
Are paired organs covering the superior surface of the kidneys
Also known as suprarenal glands because of their location
Each adrenal gland is dived into two sections, each having its own structure and function.
- Adrenal cortex
- Adrenal medulla
Adrenal cortex
Produces three types of steroid hormones
- mineralocorticoids
- Glucocorticoids
- Sex hormones
Mainly associated with Addison disease and cushion syndrome
Adrenal medulla
Produce two closely related hormones, epinephrine (adrenaline) and norepinephrine (noradrenaline)
Both hormones are activated when the body responds to crisis situations and are
considered sympathomimetic agents because they produce effects that mimic those brought about by the sympathetic nervous system.
Epinephrine produced in larger amounts
Norepinephrine raises blood pressure
Pancreas
Lies inferior to the stomach in a bend or the duodenum.
Carries digestive secretions from the pancreas to the small intestine through a large pancreatic duct. Assist in breaking down proteins, starches, and fats in the small intestine
In endocrine role the pancreas produces 2 other hormones through the islets of langerhans: glucagon produced my alpha cells and insulin proved by beta cells
Glucagon
Stimulates the release of glucose from storage sites in the liver when blood glucose levels are low ( hypoglycemia) thereby raining blood glucose level
Insulin
Clears glucose molecules from the blood by promoting their storage tissues as carbohydrates when blood glucose levels are high (hyperglycemia) thereby lowering blood glucose level and enabling cells to use glucose for energy
Pineal gland
Shaped like a pine cone and is attached to the posterior part of the third ventricle of the brain.
Produces the hormone melatonin
When melatonin production is high, ovulation is blocked, causing a delay in puberty
Endocrinology
The branch of medicine concerned with endocrine disorders
Endocrinologist
The physician who specializes in diagnoses and treatment of endocrine disorders
Cretinism
Form of hypothyroidism, develops in infants
If not treated leads to mental retardations, impaired growth, low body temp., and abnormal bone formation
Myxedema
Form of hypothyroidism, develops in adults
Symptoms include: edema, low blood levels of T3 and T4, weight gain, cold intolerance, fatigue, depression, muscle or joint pain, and sluggishness
Graves’ disease
One of the two most common disorders of hypothyroidism
Elevated metabolic rate, abnormal weight loss, excessive perspiration, muscle weakness, and emotional instability
Exophthalmos- protruded eyes
Goiter
One of the two common disorders of hyperthyroidism
Enlarged thyroid gland
Hypoparathyroidism (PTH)
Insufficient production of parathyroid hormone
Caused by primary parathyroid dysfunction or elevated blood calcium levels.
Can result from an injury or from surgical removal of the glands
Excessive production (PTH) commonly caused by a benign tumor
Hypocalcemia
Primary effect of hypoparathyroidism is a decreased blood calcium level
Causes tetany
Tetany
Muscle twitches and spasms caused by hypocalcemia (decreased calcium)
Osteitis fibrosa cystica
Demineralization of bones caused by an increase in PTH
Making them porous (osteoporosis) highly susceptible to fracture and deformity
Adenoma
Benign glandular tumor of the parathyroid
Addison Disease
Uncommon chronic disorder caused by a deficiency of cortical hormones, results when the adrenal cortex is damaged
Clinical manifestations include: muscle weakness, anorexia, gastrointestinal symptoms, fatigue, hypoglycemia, hypotension, low blood sodium (hyponatremia), and high serum potassium (hyperkalemia)
Cushing syndrome
Is a cluster of symptoms produced by excessive amounts of cortisol, adrenocorticotropic hormone (ACTH) , or both circulating in the blood.
Pheochromocytoma
Most common adrenal medulla disorder
Also known as neoplasm which produces excessive amounts of epinephrine and norepinephrine
Produce high blood pressure, rapid heart rate, stress, fear, palpitations, headaches, visual blurring, muscle spasms, and sweating
Diabetes
Refers to diabetes mellitus (DM)
Most common pancreatic disorder
Chronic metabolic disorder of impaired carbohydrates, protein, and fat metabolism due to insufficient production of insulin or the body’s inability to use insulin properly
When body cells are deprived from glucose, principal energy fuel, they begin to metabolize proteins and fats.
Ketosis
Fat metabolism produces ketones, which enter the blood
Responsible for the host of troubling and commonly life threatening symptoms of diabetes
Hyperglycemia
When insulin is lacking, sugar doesn’t enter cells but returns to the bloodstream with a subsequent rise in its concentration in the blood
Glucosuria
When blood glucose levels elevate beyond a level tolerated by the kidneys, glucose “spills” into the urine
Polyphagia
Because glucose is unavailable to cells, cellular starvation results and leads to hunger and an increased appetite
Type 1 diabetes
Usually diagnosed in children and young adults
Body doesn’t produce sufficient insulin
Daily injections of insulin required to maintain normal blood glucose level.
Report rapidly developing symptoms
Guclometer
Instrument determines the amount of sugar in the blood sample so that insulin can be injected if needed.
Insulin pump
Small device administers insulin via a portable pump, which infuses insulin continuously in small (basal) amounts through an indwelling needle under the skin
Type 2 diabetes
Most common form
Typically later in life
Risk factors include a family history of diabetes and obesity
The body is deficient in producing sufficient insulin or the body’s cells are resistant to insulin action in target tissues
The patients symptoms are commonly vague, long standing, and develop gradually
Diabetic ketoacidosis (DKA)
Diabetic acidosis
Diabetic coma
Primary complications of type 1 diabetes
May develop over several days or weeks
Can be caused by too little insulin, failure to follow a prescribed diet, physical or emotional stress, or undiagnosed diabetes
(Dx, dx) diagnosis
Secondary complications due to long standing diabetes emerge years after the initial diagnosis
Common chronic complications include diabetic retinopathy and diabetic nephropathy
Retinas blood vessels are destroyed causing vision loss and eventually blindness.
Diabetic nephropathy destruction of the kidneys causes renal insufficiency and commonly requires hemodialysis or renal transplantation
Gestational diabetes
May occur in women who aren’t diabetic but develop diabetes during the pregnancy
They develop an inability to metabolize carbohydrates with resultant hyperglycemia
Pancreatic cancer
Pain is prominent feature whether it arises in the head, body, or tail of the organ
Prognosis is poor with only 2% survival rate in 5 years
4th leading cause of cancer death in the USA
Highest incense among people ages 60 to 70
Cigarette smoking, exposure to occupational chemicals, diet high in fats, & heavy coffee intake are associated with increases incidence of pancreatic cancer
Pituitary Tumors
Abnormal growths that develop in the pituitary gland
Some tumors can restrict normal
Function of the gland causing it to produce lower levels of hormones
Vast majority of pituitary tumors are no cancerous(Benign) growths known as ADENOMAS - do not spread to other extremities
Causes compression of nearby neeves resulting in vision problems
Thyroid Carcinoma
Cancer of the thyroid gland
Classified according to the specific tissue that is affected
The malignancy usually begins with a painless, commonly hard nodule or a nodule in the adjacent lymph nodes accompanied with an enlarged thyroid
