Intro. to Endocrinology – Flashcards
Unlock all answers in this set
Unlock answersquestion
Endocrine Gland |
answer
a ductless glad that secretes hormones directly into the blood stream. |
question
Endocrine Hormone |
answer
a chemical substance produced by an endocrine gland, once released they bind to a target organ cell. |
question
Exocrine Gland |
answer
secretes its product via a duct onto laminal surface |
question
Target Organ/Cells |
answer
cell having a specific receptor that reacts with a specific hormone, antigen, antibody, antibiotic, sensitized T cell, or other substance. |
question
Second Messenger |
answer
intracellular signals acting at or situated within the plasma memrane and translating electrical or chemical messages from the environment into cellular responses. |
question
Autocrine Signaling |
answer
form of hormonal signaling in which a cell secretes a hormone, called the autocrine agent, that binds to autocrine receptors. |
question
Paracrine Signaling |
answer
hormone function in which a hormone synthesized binds to its receptor in nearby cells and affects their function. Not released into the bloodstream, but into the surrounding tissues. |
question
Endocrine Signaling |
answer
signaling in which endocrine cells release hormones that act on distant target cells. |
question
Hormone |
answer
a chemical substance that is produced and secreted into the blood by an organ or tissue, and has a specific effect on target tissue. |
question
General Description of the Hypothalamus |
answer
Located inferior and to the thalamus & just above the brain stem. Receive input from other regions of the brain, the internal orans, and the visual system. |
question
Function of the Hypothalamus |
answer
controls body temperature, hunger, thirst, fatigue, anger, circadianc ycles and helps control sexual behavior and defensive reactions such as fear and rage. |
question
General Description of the Pituitary Gland |
answer
a pea sized structure attached to the bottom of the hypothalamus. Divided into two lobes, anteror and posterior. |
question
Function of the Pituitary Gland |
answer
secretes hormones regulating homeostasis. |
question
What 9 hormones does the hypothalumus produce? |
answer
Gonadotropin Releasing Hormone (GnRH) Thyrotropin Releasing Hormone (TRH) Corticotropin Releasing Hormone (CRH) Prolactin Inhibiting Hormone (PIH) PRolactin Releasing Hormone (PRH) Melanocyte Stimulatin Hormone Inhibitin Factor (MIF) MElanocyte Stimulating Hormone Releasing Factor (MRF) GRowth Hormone Inhibiting Hormone (GHIH) Growth Hormone Releasing Hormone (GHRH) |
question
Gonadotropin Releasing Hormone (GnRH) |
answer
stimulates the release of the follicle stimulating hormone(FSH) and leutinizing hormone(LH). |
question
Thyrotropin Releasing Hormone (TRH) |
answer
question
Thyrotropin Releasing Hormone (TRH) |
answer
stimulates the release of thyroid stimulatin hormone (TSH) and prolactin. |
question
Corticotropin Releasing Hormone (CRH) |
answer
hormone & neurotransmitter involved in stress response. Stimulates the secretion of adrenocorticotropin (ATCH) |
question
Prolactin Inhibiting Hormone (PIH) |
answer
inhibits prolactin production. inhibits milk production at the mammary gland. |
question
Prolactin Releasing Hormone (PRH) |
answer
stimulates prolactin PRoduction |
question
Melanocyte Stimulating Hormone inhibiting FActor (MIF) |
answer
inhibits melanocytes stimulating hormone (MSH) production |
question
Melanocyte Stimulating Hormone Releasing Factor (MRF) |
answer
incluences melanocyte stimulating hormone (MSH) production. |
question
Growth Hormone Inhibiting Hormone (GHIH) |
answer
also called somatostatin (SS) hormone. inhibits the secretion of Human Growth Hormone (hGH) |
question
Growth Hormone Releasign Hormone (GHRH) |
answer
also called Somatocrinin-Hormones that stimulates Human Growth Hormone (hGH). |
question
What are the hormones produced by the anterior pituitary? |
answer
Follicle Stimulating Hormone (FSH) Leutinizing Hormone (LH) PRolactin (PRL) Thyroid Stimulating Hormone (TSH) Adrenocorticotropic Hormone (ACTH) Human Growth Hormone (hGH) Melanocyte Stimulating Hormone (MSH) |
question
Follicle Stimulating Hormone (FSH) |
answer
regulates the development, growth, onset of puberty, and reproductive processes of the human body. |
question
Leutiniing Hormone (LH) |
answer
essential for reproduction. |
question
Prolactin (PRL) |
answer
primarily associated with lactation |
question
Thyroid Stimulating Hormone (TSH) |
answer
regulates the endocrine function of the Thyroid gland. |
question
Andrenocorticotropic Hormone (ACTH) |
answer
stimulates the cortex of the adrenal gland, boosts synthesis of corticosterodis and sex steroids. related to the circadian rhythm in many organisms. |
question
Human Growth Hormone (hGH) |
answer
stimulates growth and cell reporduction in humans. |
question
Melanocyte Stimulating Hormone (MSH) |
answer
stimulates the production and release of melanin in skin and hair. When released in the brain it has an effect of appetite and sexual arousal. |
question
How are the anterior pituitary hormones controlled? |
answer
through negative feedback from the target gland as well as hypothalimic releasing and inhibiting hormones. |
question
How does hGH affect metabolism? |
answer
Promotes protein anabolism. Promotes lipid mobilization and catabolism. Inditectly inhibits glucose metabolism. |
question
Stimulators for release of hGH |
answer
GHRH, deep sleep, hypoglycemia, exercise, elevation of amino acids, stress, high levels of insulin. |
question
Inibitors of hGH release |
answer
hyperglycemia, GHIH, obesity, increased glucocotricoids. |
question
Gigantism |
answer
hypersecretion of hGH, abnormal rapid rate of skeletol growth in childhood, height of up to 8 feet. |
question
Acromegaly |
answer
hypersecretion of hGH, condtion in whihc carilage continues to form new bones in adulthood, enlargement of hands, feet, face, jaw. most often caused by a tumor. |
question
Pituitary dwarfism |
answer
Hyposecretion of hGH, extreme dwarfism. can be corrected if diagnosed in infancy. |
question
Posterior Pituitary |
answer
extension of the nerve tissue of the hypothalamus. |
question
Posterior Pituitary Hormones |
answer
first synthesized by the hypothalamus, then stored and secreted by the posterior pituitary. |
question
How are posterior pituitary hormones controlled? |
answer
Initally stimulated by nerve impuses from the hypothalamus, maintained through positive feedback. |
question
General Description of the Adrenal Glands |
answer
2. one superior to each kidney. divided into 2 structures, the arenal cortex and adrenal medulla. |
question
Adrenal cortext |
answer
outer portion of the adrenal glands. protices steroid hormons derives from cholesterol. |
question
Adrenal medulla |
answer
inner central portion of the adrenal glands. |
question
Zona Glomerulosa |
answer
Outter most layer of the adrenal cortex, produces mineralocorticoids, main one being aldosterone. |
question
Zona fasciculata |
answer
Middle layer of the adrenal cortexm produces glucocorticoids, main one being cortisol. |
question
Zona reicularis |
answer
inner most layer of the adrenal cortex, produces gonadocorticoids, main hormones are, dehydroepiandrasterone(DHEA), androgens, estrogen and testosterone. |
question
Mineralcorticoids |
answer
primarily regulate sodium homeostasis. Aldosterone is the main mineralocorticoids. |
question
Functions of Aldosterone |
answer
controls the kidneys ability to regulate sodium, chlride, potassium and water. Increased levels of aldosterone causes kidneys to excrete potassium in urine and reasborb sodium and water. |
question
Glucocorticoids |
answer
help regulate lood glucose homeostasis. Cortisol is the main glucocorticoids. Refulated by negative feedback except during stress. |
question
Function of Cortisol |
answer
Promotes gluconeogenesis with low glucose levels. Lipid metabolsim, excess cortisol leads to lipolysis. Meaintains normal blood pressure, excess cortisol increases, low lowers. Anti-immunity or anti-allergy effect. antiinflammatory effects. can be chronically elevated due to stress. |
question
Gonadocorticoids |
answer
incude androgens and to a much lesser extent estrogen |
question
Adrenal Insufficiency |
answer
also called addisons disease, adrenocortical hyperfunction, hypercortisolism. Occurs when underactive adrenal glands produce insufficent cortisol and occasionaly aldosterone. |
question
Primary Adrenal Insufficiency |
answer
often due to autoimmune conditions. rarer cases include adrenal tumors, tuberculosis or other infections. |
question
Secondary Adrenal Insuffiecy |
answer
due to decreased levels of adrenocorticiotropic hormone (ACTH) there is a drope in cortisol. |
question
Symptoms of Adrenal Insufficency |
answer
Fatigue, constpiation, loss of appetite, diarrhea, craving salty food, weakness, muscle and joint pain, weight loss, darkening of the skin, nausea, vomiting, abdominal pain, diziness. |
question
Treatment for Adrenal Insufficiency |
answer
Hydrocortisone, Prednisone. |
question
Adrenocorticol hyperfunction |
answer
also called Cushing's disease or hypercortisolism. often occurs when a person is exposed to chronically high levels of glucocorticoids. overproduction, highdoses of corticosteroids, tumors. |
question
symptoms of adrenocortical hyperfunction |
answer
weight gain, thinning of skin, tiredness, weak muscles, increased acne, easy bruising, round face, high blood pressure, mood swings, increased thirst, poor wound healing, weak bones, high blood sugar, depression. |
question
Treatment for adrenocorticol hyperfunction |
answer
high doses of treatment: dose adjustment tumors: surgery radiation, medication |
question
Symptons of Hyperaldosteronism |
answer
high blood pressure, excessive thirst, headaches, muscle weakness, excessive urination, cramps. |
question
Treatment of hyperaldosteronism |
answer
surgical removal of tumor |
question
What initiates the "fight or flight" response? How? |
answer
Adrenal Medulla. Increases Blood pressure, increases heart rate, increases rate of respiration, decreases digestion rate, |
question
Pheochromocytoma |
answer
hypersecretion of epinephrine, norepinephrine and dopamine. caused by a tumor on the adrenal medulla. |
question
Symptoms of Pheochromocytoma |
answer
sudden tachycardia, extreme anxiety with a sense of impending death, cold perspiration, blurred vision, headache and chest pain, stroke, or heart failure. |
question
Treatment of Pheochromocytoma |
answer
Prompt surgical removal of the tumor. |
question
catecholamines |
answer
epinephrine, norepinephrine,dopamine. |
question
General description of the Thyroid Gland |
answer
bi-lobed butterfly shaped gland located in the front and sides of the trachea below the larynx, connected by the isthmus. |
question
What hormones are produced by the Thyroid Gland? |
answer
Thyroxine (T4) Triiodothyronine (T3) Calcitonin |
question
Functions of the Thyroid Hormones |
answer
T3 & T4 control the body's metabolic rate. Calcitonin regulates calcium homeostasis. |
question
Thyroid Hormone Synthesis |
answer
1) ionized iodide is absorbed from the diet. 2) iodide trapped in the thyroid reacts with the tyrosines present on the surface of thyroglobin. 3) Iodination of tyrosine 4) coupling of T1 & T2 5) Digestion of Thyroid Hormones 6) Transport in blood. |
question
How are thyroid hormones regulated? |
answer
Through Negative Feedback. hypothalamus secretes TRH stimulating the pituitary to secrete TSH, when thyroid levels rise, hypothalamus and pituitary stop producing TSH and TRH. |
question
Physiologic Effects of the Thyroid Hormones on the body (T3 & T4) |
answer
Regulate the body's BMR. Increase Fat and carbohydrate metabolism Stimulates Protein synthesis Increase heart rate Key role in growth and development of the brain in children Enhance actions of th Catecholamines. |
question
Hypothyroidsim |
answer
used to describe the signs and symptoms assoicated with the lack of sufficien thyroid hormones. |
question
Sings and symptoms of hypothyroidism |
answer
fatigue, constipation, weight gain, coarse, dry hair, hair loss, weakness, muscle cramps and aches, irritability, dry, rough pale skin, abnormal menses, cold intolerance, depression, memory loss, decreased libido. |
question
Primary Hypothyroidism |
answer
thyroid doesn't produce enough T4. thyroid has failed, pituitary and hypothalamus functioning. |
question
Hashimoto's Thyroiditis |
answer
autoimmune disease, body attacks thyroid gland, often associated with goiter. |
question
Cretinism |
answer
congenital defect in newborns that lack a properly functioning thyroid gland, low BMR, very slow growth and sexual development, mental retardation. |
question
Hashimoto's Thyroiditis |
answer
autoimmune disease, body attacks thyroid gland, often associated with goiter. |
question
Myxedema |
answer
decreased metabolic rate which cases mental slowness, dry skin, hair loss, swollen skin, enlarged tongue, slowed speech, yellow skin, weight gain is common. older children or adults. |
question
Iodine Deficiency |
answer
lack of iodine in the diet. causes decreased production of T3 and T4, causes goiter. |
question
Other common causes of hypothyroidism |
answer
radiation, surgery, viral and bacterial infection. |
question
Secondary hypothyroidism |
answer
pituitary gland does not release enough TSH. pituitary or hypothalamus have failed, thyroid is functioning. Often caused by tumors or destruction of the pituitary. |
question
Treatment for hypothyroidism |
answer
thyroid hormone replacement therapy. LEvothyroxine synthetic T4 |
question
Hyperthyroidism |
answer
term used to describe the signs and symptoms associated with an over production of thyroid hormones. |
question
Signs and symptoms of hyperthyroidism |
answer
palpitations, nervousness, light or absent menses, breathlessness, increased bowel, insomnia, fatigue, fast heart rate, trembling hands, weight loss, muscle weakness, warm moist skin, hair loss, staring gaze, heat intolerance. |
question
Graves Disease |
answer
Most common type of hyperthyroidism. autoimmune disease, antibodies are directed against the TSH receptor sites. thyroid is stimulated to increase grwoth and function. symptoms include goiter, and exophtalmos. |
question
Other causes of hyperthyroidism |
answer
overproduction of T3 and T4 from single or multiple nodules, excess secretion of TSH |
question
Treatment for hyperthyroidism |
answer
anti-thyroid drug therapy, radioactive iodine, and/or surgical removal of all or part of the thyroid. |
question
General Description of the Parathyroid Gland |
answer
4-5 parathryid glands are embedded in the thyroid gland. Primary hormone is Parathyroid Hormone (PTH) Not dependent on pituitary or hypothalamus. |
question
Physiological effects of the bones of PTH |
answer
reduces the effect of new bone formation. Increases the amount of bone degradation which yields calcium and phosphate. |
question
Physiological effects of the kidneys of PTH |
answer
causes calcium to be reabsorbed from urine and renter the blood. PTH causes phosphate to be removed from bone into the bloodstream. PTH inhibits the reabosrption of phosphate. |
question
PTH effects in the intestines |
answer
PTH increases the body absorption of calcium from food. Vitamin D permits calcium ions to e transported into blood. |
question
Calcitonin |
answer
protein produced by the parafollicular cells of the thyroid. These cells are located next to the thyroid secreting cell hormones in the thyroid gland. |
question
Physiological effects of calcitonin in the body. |
answer
Removes excess calcium from blood sends it to bones to increase bone formation. Inhibits bone breakdown. promtoes conservation of hard bone matrix. |
question
Calcium homeostasis |
answer
acheived through combined action of PTH and calcitonin. |
question
Low blood levels of calcium |
answer
stimulate secretion of PTH, inhibits secretion of Calcitonin |
question
High Blood Levels of Calcium |
answer
inhibit PTH stimulate secretion of calcitonin |
question
Physiological Importance of Calcium homeostasis |
answer
leads to normal: blood clotting, strong teeth and bones, cell membrane permeability. |
question
Hypoparathyroidism |
answer
hyposecretion of PTH, causes low calcium levels, high phosphate levels. Treated with vitamin D and calcium supplements. |
question
Hyperparathyroidism |
answer
hypersecretion of PTH, high calcium, low phosphate, caused by tumors, treatment is removal of tumor. |
question
Parathyroidectomy |
answer
surgical removal of all four parathyroid glands. |
question
General description of the Testes |
answer
paired organs found within the scrotum. composed of coils of sperm-producing seminiferous tubules, between these are the interstitial cells of Leydig that produce testosterone. |
question
Testosterone |
answer
responsible for growth and maitenance of male sexual characteristics, regualtes spermatogenesis, stimulates descent of the testis. |
question
Inhibin (MEN) |
answer
secreted by the Sertoli Cells (sperm attaches to it until they are mature) inhibits secretion of the Follicle stimulating hormone. (FSH) |
question
What hormone stimulates the testes to produce sperm? |
answer
Folicle Stimulating Hormone (FSH) |
question
What hormone stimulates interstitial cells in the testes to develop and produce testosterone? |
answer
Leutinizing hormone (LH) |
question
Increased Testosterone Levels |
answer
Can be caused by testicular, adrenal, or pituitary tumors. In young males could be precocious puberty. |
question
Decreased Testosterone Levels |
answer
Hypogonadism, Klinefelter's Syndrome, Orchiectomy, Delayed Puberty, Elderly Men, Alcohol use and Abuse. |
question
What cells produce estrogen and progesterone? |
answer
Granulosa cells and thecal cells. |
question
Estrogen |
answer
secreted by the follicle cells. promotes the maturation of the ovum stimulates growth of blood vessels in the endometrium responsible for secondary sex characteristics in women. |
question
Follicle |
answer
Fundamental reproductive unit which consists of one oocyte(egg) surrounded by a cluster of granulosa cells. |
question
Function of the Follicle |
answer
Maintain and nurture the oocyte and release it at the proper time. PRovide hormonal support for the fetus. |
question
Progesterone |
answer
stimulated by LH, promotes storage of glycogen and further growth of blood vessels which become a placenta, influences the cells of the mammory glands. |
question
Inhibin (WOMEN) |
answer
secreted by the corpus luteum, decreases the secretion of FSH and GnRH. |
question
Mensus |
answer
activity of the ovaries and the anterior pituitary gland and the resultant changes in the ovaries and uterus. involves FSH, LH, estrogen and progesterone. |
question
Menstrual Phase of Mensus |
answer
loss of the functional layer of the endometrium, lasts 2-8 days, secretion of FSH increases. |
question
Follicular Phase of Mensus |
answer
growht of follicles and secretion of estrogen is stimulated by FSH, functional layer regenerating, ends at OVulation. |
question
Luteal Phase of Mensus |
answer
Under the influence of LH, the ruptured follicle becomes the corpus luteum, which secretes progesterone |
question
Fertilization |
answer
conception. takes place in the fallopian tubes when a sperm enters an ovum. |
question
Embryo |
answer
developing human individual from the time of implantation to about 8 weeks of gestation. |
question
Fetus |
answer
developing human from 9 weeks to birth. |
question
Placenta |
answer
composed of both maternal and fetal tissue, serves as the site of nutrient exchange, oxygen and co2 exchange, secretes numerous hormones. |
question
Umbilical Cord |
answer
conencts the fetus to the placenta |
question
Placental Hormones |
answer
Human Chorionic Gonadotropin (hCG) Placental Progesterone Placental Estrogens Humon Chorionic Somatommamotropin(hCS) |
question
Human Chorionic Gonadotropin (hCG) |
answer
first hormone secreted by the blastocyst, detected in maternal plasma and urine about 3-9 days after conception. |
question
Function of hCG |
answer
matins the corpus luteum, stimulates secretion of progesterone and estradiol, stimulates fetal adreanal glads, in male fetuses, stimulates the early secretion of testosterone which is critical to masculinize the genital tract. |
question
Placental Progesterone |
answer
essential for successful implantation, inital sustenance and long term maitenance of the fetus, induces prolactin and mammory gland development, increases ventilation, quiets uterine muscle activity, |
question
Placental Estrogens |
answer
Progessive increases in estradiol, estrone, estriol throught pregnancy, stimulates growth of uterine muscles, relax and softens the pelvic ligaments, augment growth of the duct system int he breasts. |
question
Human Chorionic Somatomammotropin (hCS) |
answer
human placental lactogen, stimulates lipolysis and is an insulin antagonist, |
question
Prolactin |
answer
stimulates lactogenesis of the breasts, and suppreses reproductive function of the mother. |
question
Relaxin |
answer
relaxes the mother's pelvis, softens the cervvix, decreases uterine muscle contraction. |
question
Miscarriage |
answer
10-15% of all conceptions, majority occurs within 14 days, later miscarriages refelct bad attatchement or abnormalities, Dx is made ith beta hCG assasy and ultrasound. |
question
Ectopic Pregnancy |
answer
fertilized egg implants in the fallopian tube, leading cause of maternal mortality, Dx made with beta hCG assays, ultrasound, and laparascopy. |
question
What are the laboratory tests to Dx Adrenal Cortex Disorders? |
answer
Plasma cortisol levels, Basal ACTH, Cortisol 24-hour Urine and ACTH stimulation test. |
question
What are the laboratory tests to Dx Adrenal Medulla Disorders? |
answer
Plasma epinephrine, norepinephrine, and dopamine levels, urine 24 hour, metanephrine and vanillylmandelic Acid (VMA) levels. |
question
When is the peak and trough for Plasma Cortisol? |
answer
peak : 0800-0900 Trough: 2300-0000 |
question
What is the most sensitive test for hypothyroidism, speciment requirements and reference range? |
answer
Thyroid Stimulating Hormone Serum or plasma nonlipemic non hemolyzed .4-8.9 mU/L |
question
Total T4 |
answer
measures Thyroxine in Serum. Rules out hypo or hyper thyroidism, used to diagones any congenital defects in neonates. Serum or heel stick (neonate screen) Referance range Adult 5-12 ug/dL neonate 32-216 ug/dL |
question
Total T3 |
answer
useful in hyperthyroidsim, limited value for hypothyroidism. Serum is preferred Adult 88-150 ng/dL Neonate 32-216 ng/dL |
question
FT3 - Free triiodothyronine |
answer
evaluates thyroid function, measures FREE t3 in blood. USed to rule out T3 thyrotoxicosis, evaulate thyroid replacement therapy and clarify protein-binding abnormalities. .2-.52 ng/dL |
question
TBG Thyroxine Binding Globulin |
answer
distinguishes between hyperthyroidism causing elevated T4 and euthyroid patients iwth increased T4 binding, hereditary deficiences of TBG Serum 16-34 ug/mL |