Chapter 13 Flashcards
Endocrine System
Body system that includes endocrine glands in various locations in the body that produce and secrete hormones directly into the blood.
These glands include the pituitary gland, hypothalamus, pineal gland, thyroid gland, parathyroid glands, thymus, pancreas, adrenal glands, ovaries, and testes.
Gland
Structure of the endocrine system that produces and secretes one or more hormones into the blood.
Homeostasis
State of equilibrium of the internal environment of the body. The endocrine system plays a role in homeostasis by using hormones to regulate body fluids, electrolytes, glucose, cellular metabolism, growth, and the sleep-wake cycle (circadian rhythm).
Hormone
Chemical messenger of the endocrine system that is produced by a gland and secreted into the blood. It exerts an effect on a gland or an organ that has a receptor for that specific hormone to bind to.
Pituitary gland
Endocrine gland in the brain that is connected by a stalk of tissue to the hypothalamus. The pituitary gland sits in the bony cup of the sella Turkic a in the sphenoid bone.
It is the “master gland of the body.” Also known as the hypophysis. It consists of an anterior lobe and posterior lobe, each of which has a different endocrine function.
Adrenocorticotropic Hormone (ACTH)
Hormone produced and secreted by the anterior pituitary gland. It stimulates the cortex of the adrenal gland to secrete its hormones.
Anterior pituitary gland
Lobe of the pituitary gland that produces and secretes seven hormones: thyroid-stimulating hormone (TSH), prolactin (PRL), follicle-stimulating hormone (FSH), luteinizing hormone (LH), adrenocorticotropic hormone (ACTH), growth hormone (GH), and melanocyte-stimulating hormone (MSH).
Also known as the adenohypophysis because it is a true gland.
Follicle-stimulating hormone (FSH)
Hormone produced and secreted by the anterior pituitary gland. In females, it stimulates follicles in the ovary to produce mature ova and to secrete the hormone estradiol.
In males, it stimulates the seminiferous tubules of the testes to produce spermatozoa
Gonadotropins
Category of hormones that stimulates the male and female sex glands (gonads). It includes FSH and LH
Growth hormone (GH)
Hormone produced and secreted by the anterior pituitary gland.
It stimulates growth and protein synthesis in all cells. It increases height and weight during childhood and puberty
Luteinizing hormone (LH)
Hormone produced and secreted by the anterior pituitary gland.
In females, it stimulates a follicle in the ovary to release a mature ovum each month. It stimulates the corpus luteum (ruptured ovarian follicle) to secrete estradiol and progesterone.
In males, it stimulates the interstitial cells of the testes to secrete testosterone.
Melanocyte-stimulating hormone (MSH)
Hormone produced and secreted by the anterior pituitary gland, it is secreted in pregnant women and stimulates melanocytes in the skin to produce melanin. This causes a darkened pigmentation on the face and abdomen.
Prolactin (PRL)
Hormone produced and secreted by the anterior pituitary gland. It stimulates the development of the breasts during puberty and stimulates them to produce milk for breast feeding.
Thyroid-stimulating hormone (TSH)
Hormone produced and secreted by the anterior pituitary gland.
It stimulates the thyroid gland to grow and to secrete the thyroid hormones T3 and T4.
Antidiuretic hormone (ADH)
Hormone produced by the hypothalamus but stored in and secreted by the posterior pituitary gland.
ADH acts on the tubules of the kidneys to increase the reabsorption of sodium and water back into the blood.
This decreases urine output and helps to maintain a normal blood volume and blood pressure.
Oxytocin (OXT)
Hormone produced by the hypothalamus but stored in and secreted by the posterior pituitary gland. It stimulates the pregnant uterus to contract during labor and childbirth and causes the uterus to contract after birth to prevent hemorrhaging.
It stimulates the breasts to release milk for breastfeeding.
Posterior pituitary gland
Lobe of the pituitary gland that stores and secretes ADH and oxytocin produced by the hypothalamus; it secretes these hormones in response to a nerve impulse from the hypothalamus. Also known as the neurohypophysis.
Hypothalamus
Endocrine gland in the brain just below the thalamus. The hypothalamus secretes hormones that stimulate or inhibit the secretion of hormones from the anterior pituitary gland.
It also produces oxytocin hormone and antidiuretic hormone that are stored in the posterior pituitary gland.
Melatonin
Hormone secreted by the pineal gland.
It regulates the 24 hour sleep-wake cycle and the onset and duration of sleep.
Pineal gland
Endocrine gland between the two lobes of the thalamus. It secretes the hormone melatonin.
Calcitonin
Hormone secreted by the thyroid gland.
It regulates the amount of calcium in the blood. If the calcium level is too high, calcitonin suppresses bone breakdown and increase the excretion of calcium in the urine.
Euthyroidism
Steady state of normal functioning of the thyroid gland producing and secreting its hormones.
Triiodothyronine (T3)
Hormone secreted by the thyroid gland. Most of it is changed into T3 by the liver.
Thyroid gland
Endocrine gland in the neck that secretes the hormones T3, T4, and calcitonin when stimulated by TSH from the anterior pituitary gland.
Parathyroid glands
Four small endocrine glands on the posterior surface of the thyroid gland. They secrete parathyroid hormone.e
Parathyroid hormone
Hormone secreted by the parathyroid glands. It regulates the amount of calcium in the blood.
If the calcium level is too low, parathyroid hormone stimulates the release of calcium from the bones and into the blood.
Thymus
Endocrine gland posterior to the sternum and within the mediastinum. It secretes hormones called thymosins.
Thymosin
Secreted by the thymus. It causes immature T cell lymphocytes in the thymus to mature.
Glucagon
Hormone secreted by alpha cells in the islets of Langerhans. It stimulates the liver to convert glycogen (glucose stored in the liver) to glucose and realest it into the blood.
Glucose
A simple sugar that is the main source of energy for cellular metabolism. Glucose in the blood comes from digested foods and from glycogen when it is converted into glucose by the hormone glucagon.
Glycogen
Glucose stored in the liver. it is converted to glucose by the hormone glucagon from the pancreas and by the hormone cortisol from the adrenal cortex.
Insulin
Hormone secreted by beta cells in the islets of Langerhans. It transports glucose into the cells where it is metabolized for energy.
Pancreas
Endocrine gland posterior to the stomach. it contains the islets of Langerhans (alpha, bets, and delta cells) that secrete the hormones glucagon, insulin and somatostatin.
Somatostatin
Hormone secreted by delta cells in the islets of Langerhans.
It inhibits the secretion of glucagon and insulin from the pancreas. It inhibits the secretion of growth hormone from the anterior pituitary gland.
Adrenal cortex
Outer layer of the adrenal gland.
When stimulated by ACTH from the anterior pituitary gland, the adrenal cortex secretes three groups of hormones: mineralocoritocoids (primarily aldosterone), glucocorticoids (primarily cortisol), and androgens (male sex hormones).
Adrenal glands
Endocrine glands on top of the kidneys. the adrenal gland consists of two parts: the cortex (an outer layer) and the medulla (an inner layer), each of which is a gland that secretes to own hormones.
Adrenal medulla
Inner layer of the adrenal gland. It secretes the hormones norepinephrine, epinephrine, and dopamine.
Aldosterone
Most abundant and biologically active of the mineralocorticoid hormones secreted by the adrenal cortex.
When the blood pressure is low, aldosterone causes reabsorption of sodium and water from tubules in the kidney into the blood.
This increases the blood volume and the blood pressure.
Androgens
Group of male sex hormones secreted by the adrenal cortex and by the testes. It includes testosterone, the most abundant and biologically active of the androgens.
Cortisol
Most abundant and biologically active of the glucocorticoid hormones secreted by the adrenal cortex.
It stimulates the liver to convert glycogen to glucose to increase the level of glucose in the blood.
It decreases the formation of proteins and new tissues, and it has an anti-inflammatory effect.
Dopamine
Hormone secreted by the adrenal medulla during times of stress. It is also a neurotransmitter between the brain and spinal cord of the nervous system.
Epinephrine
Hormone secreted by the adrenal medulla in response to a nerve impulse from the sympathetic division of the nervous system during times of danger or anger.
It produces the “fight-or-flight” response.
glucocorticoids
Group of hormones secreted by the adrenal cortex, of which aldosterone is the most abundant and biologically active.
Mineralocorticoids
Group of hormones secreted by the adrenal cortex, of which aldosterone is the most abundant and biologically active.
Norepinephrine
Hormone secreted by the adrenal medulla. It is also a neurotransmitter between the brain and the spinal cord of the nervous system.
Estradiol
Most abundant and biologically active of all the female sex hormones. Estradiol is secreted by the follicles and corpus luteum of the ovary when stimulated by FSH from the anterior pituitary gland.
Ovaries
Endocrine glands near the uterus; they are the female sex glands (gonads). FSH from the anterior pituitary gland stimulates the follicles of the ovary to secrete estradiol.
LH from the anterior pituitary gland stimulates the corpus luteum to secrete estradiol and progesterone.
The cells around the follicles secrete the male sex hormone testosterone.
Progesterone
Female sex hormone secreted by the corpus luteum of the ovary when stimulated by LH from the anterior pituitary gland.
Testes
Endocrine glands on either side of the scrotum; they are the male sex glands (gonads). Also known as testicles.
FSH from the anterior pituitary gland stimulates their seminiferous tubules to produce spermatozoa. LH from the anterior pituitary gland stimulates their interstitial cells to secrete testosterone.
Testosterone
Most abundant and biologically active of the male sex hormones. Testosterone is secreted by the interstitial cells of the testes when stimulated by LH from the anterior pituitary gland.
Antagonism
Process in which two hormones exert opposite effects
Inhibition
Action of a hormone that inhibits an endocrine gland from secreting its hormones
Receptor
Structure on the cell membrane of an organ or gland where a hormone binds and exerts an effect.
Stimulation
Action of a hormone that stimulates an endocrine gland to secrete its hormones or stimulates a receptor on an organ or tissue.
Synergism
Process in which two hormones work together to accomplish an enhanced effect.
Hyperpituitarism
Hypersecretion of one or all of the hormones of the anterior pituitary gland. It is caused by a benign tumor (adenine) in the anterior pituitary gland.
Treatment: Drug therapy to suppress secretion of the hormones or surgery to remover the adenoma, with radiation therapy to destroy any remaining adenoma.
Hypopituitarism
Hyposecretion of one or more of the hormones of the anterior pituitary gland. It is caused by an injury or a defect in the anterior pituitary gland.
Panhypopituitarism is hyposecretion of all of the hormones.
Treatment: Drug therapy to replace the hormones
Galactorrhea
Hypersecretion of prolactin. It is caused by an adenoma in the anterior pituitary gland. In women, the high level of prolactin stimulates the breasts to produce milk, even though the patient is not pregnant.
Failure of lactation
Hyposecretion of prolactin. It is cause by a defect in the anterior pituitary gland. The low level of prolactin prevents the development of the lactiferous lobules.
Gigantism
Hypersecretion of growth hormone during childhood and puberty.
Acromegaly
Hypersecretion of growth hormone during adulthood. It is caused by an adenoma in the anterior pituitary gland.
Dwarfism
Hyposecretion of growth hormone during childhood and puberty. It is caused by a defect in the anterior pituitary gland.
Syndromes of inappropriate ADH (SIADH)
Hypersecretion of ADH. It is caused by an adenoma in the posterior pituitary gland. The high level of ADH acts on the kidneys to increase reabsorption of excessive amounts of water and some sodium from the kidney tubules back into the blood.
Diabetes insipidus (DI)
Hyposecretion of ADH. It is caused by a defect in the posterior pituitary gland, a brain infection, head trauma, or heredity. The low level of ADH decreases reabsorption of sodium and water from the kidney tubules and so excessive amounts of water are excreted in the urine.
Uterine intertia
Hyposecretion of oxytocin. It is caused by a defect in the posterior pituitary gland. Before a woman gives birth, the low level of oxytocin in her blood causes weak and uncoordinated contractions of the pregnant uterus. This prolongs labor and delays the birth of the baby.
Seasonal affective disorder (SAD)
Hypersecretion of Melatonin. The exact cause is not known. Melatonin is normally secreted during the night. The longer nights and decreased hours of sunshine during the winter months may disrupt the body’s circadian rhythm and increase the secretion of melatonin.
Hyperthyroidism
Hypersecretion of T3 and T4 thyroid hormones. It is caused by an adenoma in the thyroid gland.
The high levels of T3 and T4 cause tremors of the hands, tachycardia, palpitations, restlessness, nervousness, diarrhea, insomnia, fatigue, and generalized weight loss.
Graves’ disease
Most common type of hyperthyroidism. Autoimmune disease in which the body produces antibodies that stimulate TSH receptors on the thyroid gland, and this increase the production of thyroid hormones.
The entire thyroid gland becomes enlarged and there is exophthalmos.
Exophthalmos
Eyes pop out
Hypothyroidism
Hyposecretion of T3 and T4 thyroid hormones. It is usually caused by an inadequate amount of iodine in the diet. It can also be caused by hyposecretion of TSH from the anterior pituitary gland or by treatments for hyperthyroidism that remove the thyroid gland.
Thyroid carcinoma
Malignant tumor of the thyroid gland. There is hoarseness, neck pain, and enlargement of the thyroid gland and nearby cancerous lymph nodes.
Surgery to remove the thyroid gland, with radiation therapy to destroy the remaining thyroid gland.
Hyperparathyroidism
Hypersecretion of parathyroid hormone. It is caused by an adenoma in the parathyroid gland. The high level of parathyroid hormone stimulates the release of too much calcium from the bones, and the calcium level in the blood is too high.
Hypoparathyroidism
Hyposecretion of parathyroid hormone. It is caused by the accidental removal of the parathyroid glands during surgery to remove the thyroid gland.
Treatment: Parathyroid hormone supplement drug
Hyperinsulinism
Hypersecretion of insulin. It is caused by an adenoma in the pancreas. The high level of insulin causes hypoglycemia. There is shakiness, headache, sweating, dizziness, and even fainting.
If untreated, hypoglycemia can progress to insulin shock and then coma as the blood glucose level becomes too low to support brain activity.
Treatment: supplemental sugar drink or dextrose intravenous fluids; surgery to remove the adenoma.
Insulin resistance syndrome (IRS)
hypersecretion of insulin. this is not caused by an adenoma. It occurs when receptors on body cells develop a resistance and do not allow insulin to transport glucose into the cell.
Diabetes mellitus (DM)
Hyposecretion of insulin. It is caused by an inability of the beta cells of the pancreas to secrete enough insulin. A person who has diabetes mellitus is a diabetic.
Diabetic ketoacidosis (DKA)
A high level of ketones in the blood. This occurs in untreated or uncontrolled diabetes mellitus when there is no insulin to metabolize glucose for cellular energy, and the body turns to other sources of energy such as fat or protein.
Hyperaldosteronism
Hypersecretion of aldosterone. It is caused by an adenoma in the adrenal cortex.
Hypoaldosteronism
Hyposecretion of aldosterone. it is caused by a defect in the adrenal cortex. There is dizziness, a low level of sodium in the blood, weakness, and decreased blood pressure.
Cushing disease and syndrome
Cushing disease is caused by hypersecretion of cortisol from an adenoma in the adrenal cortex. Cushing syndrome occurs in a patient who takes corticosteroid drugs on a long-term basis.
Addison disease
Hyposecretion of cortisol. This is an autoimmune disorder in which the body produces antibodies that destroy the adrenal cortex. Also known as adrenal insufficiency.
Adrenogenital syndrome
Hypersecretion of androgens. It is caused by an adenoma in the adrenal gland. In girls, the clitoris and labia enlarge and resemble a penis and scrotum. In boys, it causes precocious puberty. In adul females, It causes virility and masculine facial features and body builds hirsute skin and amenorrhea.
Pheochromocytoma
Hypersecretion of norepinephrine and epinephrine because of an adenoma in the adrenal medulla. This type of adenoma has a characteristic appearance of gray-tan tissue.
Precocious puberty
Hypersecretion of estradiol in a female child. It is caused by an adenoma in the ovary.
Infertility
Hyposecretion of estradiol in an adult female or an imbalance in the amount of estradiol and progesterone. There is a lack of ovulation, abnormal menstruation, or a history of miscarriages.
Menopause
Hyposecretion of estradiol in an adult female. This is a normal result of the aging process in which the ovaries secrete less and less estradiol. It can also be caused by surgical removal of the ovaries due to cancer.
Precocious puberty
Hypersecretion of testosterone in a male child. it is caused by an adenoma in the testis.
Gynecomastia
Hyposecretion of testosterone in an adult male. This is a normal result of the aging process in which the testes secrete less testosterone.
Infertility
Hyposecretion of testosterone in an adult male. It is caused by failure of one or both of the testes to descend into the scrotum before birht.
Antithyroglobuolin antibodies
Test that detects antibodies against thyroglobulin. A positive test result indicates Hashimoto thyroiditis or Graves’ disease.
Calcium test
Test that measures the level of calcium to determine if the parathyroid gland is secreting a normal amount of parathyroid hormone.
Cortisol level
Test that measures the level of cortisol to determine if the adrenal cortex is secreting a normal amount of cortisol.
Fasting blood sugar (FBS)
Test that measures the blood glucose level after the patient has fasted for at least 12 hours. The result indicate if the pancreas is secreting a normal amount of insulin.
FSH assay and LH assay
Test that measures the levels of FSH and LH to determine if the anterior pituitary gland is secreting a normal amount of these hormones. Part of an infertility work up for men and women.
Glucose self-testing
Self-test that measure the level of glucose. Patients with diabetes test their own blood glucose level one or more times each day.
Glucose tolerance test (GTT)
Test that measure the level of glucose to determine if the pancreas is secreting a normal amount of insulin. After the patient has fasted for 12 hours, a blood specimen is obtained.
Growth hormone (GH)
Test that measures the level of GH to determine if the anterior pituitary gland is secreting a normal amount of growth hormone.
Hemoglobin A1c (HbA1c
Test that measures the A1c fraction of hemoglobin in red blood cells. Hemoglobin A1c binds with glucose in the blood. Because red blood cells only live about 12 weeks, the hemoglobin A1c result indicates the average level of blood glucose during the previous 12 weeks.
Testosterone
Test that measures the levels of total testosterone and free testosterone to determine if the testes are secreting a normal amount of testosterone.
Thyroid function tests (TFTs)
Test that measure the levels of T3 and T4 and TSH to determine if the thyroid gland is secreting normal amounts of thyroid hormones.
ADH stimulation test
Test that measures the level of estradiol to determine if the ovaries are secreting a normal amount.
Urine dipstick
Test that measures glucose, ketones, and other substances in the urine.
Vanillylmandelic acid (VMA
A 24 hour urine test that measures the levels of epinephrine and norepinephrine to determine if the adrenal medulla is secreting a normal amount of these hormones. VMA, a by-product of these hormones, is measured.
radioactive Iodine uptake (RAIU) and thyroid scan
Procedure that combines a thyroid scan with a radioactive iodine uptake procedure. The thyroid scan shows the size and shape of the thyroid gland. The radioactive iodine uptake shows how well the thyroid gland is able to absorb radioactive iodine from the blood.
Thyroid ultrasonography
Procedure that uses sound waves generated by a transducer that is placed on the neck. It shows thyroid enlargement and thyroid nodules.
ADA diet
Special physician-prescribed diet for diabetic patients that follows the guidelines of the American Diabetes Association (ADA). The amounts of carbohydrate and fat are limited. The physician orders the upper limit for the total daily number of calories for a diabetic patient in the hospital.
Antidiabetic drug
Treats type 2 diabetes mellitus by stimulating the pancreas to secrete more insulin or by increasing the number oof insulin receptor on cells.
These drugs are given orally.
Anti thyroid drug
Treats hyperthyroidism by inhibiting the production of T3 and T4. Anti thyroid drugs are given orally on a continuing basis. Alternately, radioactive sodium iodide131 is given orally but it acts in an entirely different way.
Corticosteroid drug
Mimics he action of cortisol from the adrenal cortex. It is used to treat severe inflammation and as hormone replacement therapy for Addison disease.
Growth hormone supplement drug
Provide growth hormone
Insulin
Treats type 1 and type 1.5 diabetes mellitus. It can also be used to treat type 2 diabetes mellitus that cannot be controlled with oral antidiabetic drugs.
Thyroid supplement drug
Treats a lack of thyroid hormones and hypothyroidism
Adrenal to my
Procedure to remove the adrenal gland because of an adenoma or cancerous tumor.
Fine-needle biopsy
Procedure that uses a fine needle to take a small sample of tissue from a thyroid nodule. The tissue is sent to the pathology department to determine if the nodule is benign or cancerous.
Parathyroidectomy
Procedure to remove one or more of the parathyroid glands to treat hyperparathyroidism. Also, a parathyroidectomy can occur accidentally when part of the thyroid gland is surgically removed.
Thymectomy
Procedure to remove the thymus in patients with myasthenia gravis, an autoimmune disease.
Thyroidectomy
Procedure to remove the thyroid gland. All of the thyroid gland can be removed or just one part or just one lobe.
Transsphenoidal hypophysectomy
Procedure to remove an adenoma from the pituitary gland. The pituitary gland is difficult to visualize through an incision in the cranium, so the surgical instruments are inserted through the nose and an incision is made in the sphenoid sinus.
ACTH
Adrenocorticotropic hormone
ADA
American Diabetes Association, American Dietetic Association
ADH
Antidiuretic hormone
AODM
Adult-onset diabetes mellitus
CDE
Certified diabetes educator
CGM
Continuous glucose monitoring
DI
Diabetes mellitus
FBG
Fasting blood glucose
FBS
Fasting blood sugar
FSH
Follicle-stimulating hormone
FTI
Free thyroxine index
GDM
Gestational diabetes mellitus
GH
Growth hormone
GTT
Glucose tolerance test
HbA1c
Hemoglobin A1c
IDDM
Insulin-dependent diabetes mellitus
IRS
Insulin resistance syndrome
LADA
Latent autoimmune diabetes in adults
LH
Luteinizing hormone
MSH
Melanocytes-stimulating hormone
NIDDM
Non-insulin-dependent diabetes mellitus
OGTT
Oral glucose tolerance test
OXT
Oxytocin
PRL
Prolactin
RAIU
Radioactive iodine uptake
SAD
Seasonal Affective disorder
SIADH
Syndrome of inappropriate antidiuretic hormone
T3
Triiodothyronine
T4
Thyroxine
T7
Free thyroxine index (FTI)
TFTs
Thyroid function tests
TSH
Thyroid-stimulating hormone
VMA
Vanillylmandelic acid
