Test 5 Flashcards
Hormones trigger a desired reaction in the
Target cell
All organs of the endocrine system are
Glands
Target cells respond by chemical changes within the target cell, these changes are the
“Second messenger”
Steroidal hormones pass through cell membranes, integrating directly with
DNA
The endocrine system is a major controller of the body’s
Homeostasis
Negative feedback loops
Oppose a change (negate) in a controlled condition.
Example- if too hot, body will sweat to cool down
Positive feedback loops
Temporarily amplify the change that is occurring.
Example - if bleeding, blood flow to area of injury will increase so that platelets clot together
Hypersecretion
Growth hormone anomaly.
Normal growth years = gigantism
After normal growth years = acromegaly
Hyposecretion
Growth hormone anomaly.
Normal growth years = dwarfism
Oxycytosin and ADH (antidiuretic hormone) are produced by the
Hypothalamus gland
Releasing and inhibiting hormones of the hypothalamus gland control
The release of anterior pituitary hormones and help control homeostasis
Cortex means
Outer
Medulla means
Inner
Failure of blood glucose homeostasis results in
Diabetes Mellitus
Nearly every organ and system has some
Endocrine function
Gherlin
Lining of the stomach - the “hunger hormone”
Boosts appetite, slows metabolism
Leptin
Fat cells
Regulates hunger, fat burning.
Osteoporosis is considered
A destructive pathology and will require a decrease in technique (KVP) when imaging
Bone demsitometry (DEXA)
Dual energy xray absorptionmetry
Routine, scans done of AP lumbar spine and AP bilateral hips
Patient scan results are compared to:
-A person in peak bone health (t-score)
-a person of similar age, ht., wt, sex, ethnicity (z-score)
-patient ranked into one of 3 categories (normal, osteopenia, or osteoporosis)
Causes of bone loss
Aging, ethnicity, post menopausal hormone changes, body habitus, poor diets, inactivity, certain long term meds (steroids, anti-convulsants)
Radiographic appearance of bone loss
Cortical bone thinning
Resorption of the endosteal (inner bone) w/irregularities
Best demonstrated in spine and pelvis
Compression fractures or anterior displacement of vertebral bodies on one another
In the skull, may demonstrate a spotty loss of density and bone loss in the sella turcica and dorsum sallae
Treatment of bone loss
Prevention is the best cure:
Weight baring exercise, hormone replacement therapy, adequate vitamin/mineral intake, supplements, medications
Osteomalacia
Insufficient mineralization of the adult skeleton after closure of the epiphyseal plates, caused by inadequate intake of calcium, vitamin d, and phosphorus
Radiographic appearance of Paget’s In the skull
a well defined area of radiolucency is seen in the destructive phase of the disease. In the repair process,there is marked development of ossified islands that give the skull a mottled appearance.
Radiographic appearance of Paget’s in the spine
Enlargement of the vertebral body occurs with an increase in cortical bone. Occasionally there is a sclerotic appearance of the entire vertebra known as “ivory vertebra”
Treatment for Paget’s disease
There is no known cure that exists.
The progression of Paget’s disease can be slowed by
Administering bio phosphates and calcitonin - these meds minimize the resorption of bones and inhibit osteoclastic activity.
Dwarfism
Insufficient secretion of growth hormone in the adolescent - bones do not grow
Normal fasting blood glucose =
70-120mg/dL
Blood glucose greater than 120 =
Diabetes
Alpha cells
Glucagon
Beta cells =
Insulin
Iodine deficiency is known to cause
Goiter
Risk factors for type II diabetes
Age (especially after age 40), obesity, inactivity, African and Hispanic descent, Native American and pacific island descent
Parathyroid function
Blood calcium homeostasis, increases blood calcium
Malignant thyroid neoplasms are treated by
Thyroidectomy
I123 therapy (to ablate any residual cancerous tissue)
Cretinism developmental abnormalities include
Short stature, protruding tongue, sparse hair, dry skin, protruding abdomen, mental retardation, underdevelopment of face and calvaria
Endocrine
“Within the organ” - gland secretions absorbed directly into the bloodstream
Exocrine
“Out of organ” - gland secretions carried by duct
Target cells
“Target of hormone” - specific cells that bind to specific hormones
Nonsteroidal hormones
Water soluable, act as “first messengers”, chemical message from gland to target cells, hormone binds to to target cell receptors which respond by chemical changes within the target cells
Steroidal hormones
Lipid (fat) soluable, able to pass through cell and nuclear membranes into nucleus, hormones act upon the cell DNA, formation of a new protien in cytoplasm which produces the desired response.
Hyper secretion of hormones results in
Exaggerated response of target cells due to too much of the hormone being produced
Hypo secretion of hormones will result in
Insufficient response of target cells due to too little of the hormone being produced
Homeostasis
“Staying”, “same” a maintenance of a relative consistency (temperature, salt content, pH, fluid volume, pressure, oxygen concentration)
Prostaglandins/tissue hormones
Produced in a tissue, diffuse only a short distance into tissue, act only on cells within that tissue, do not travel through blood stream; effect many body functions (respiration, blood pressure, gastro secretions, inflammation, reproductive systems)
Pituitary gland/hypophysis/”master gland”
Small (about pea sized) but mighty; 2 different glands - anterior and posterior protected by a bony structure of the sella turcica and sphenoid bone
Adenohypophysis
The anterior lobe of the pituitary gland which secretes tropic hormones
Neurohypophysis
The posterior lobe of the pituitary gland which releases two hormones, ADH and oxycytosine
Sella turcica
Protects the pituitary gland along with the sphenoid
Tropic hormones
Stimulates other glands (endocrine) to secrete hormones (TSH, ACTH, ESH, LH)
TSH - Thyroid Stimulating Hormone
Stimulates the thyroid gland to increase secretion of hormone
ACTH - Adrenocorticotropic Hormone
Stimulates adrenal gland to increase secretion of hormone
FSH - Follicle Stimulating Hormone
Stimulates ovarian follicle to grow, stimulates secretion of estrogen
LH - Luteinizing Hormone
stimulates mature ovarian follicle cell to rupture; ripe ovum expelled from ovary
HGH - human growth hormone
Acceleration of cellular anabolism
ADH - antidiuretic hormone
Hormone released by neurohypophysis; decreases urine volume
Oxytocin
Hormone released by neurohypophysis which stimulates labor in gestational female and stimulates production of milk in breasts
Hypothalamus
Homeostasis of body temperature, thirst, appetite, produces ADH and oxycytosine, also produces releasing and inhibiting hormones
Thyroid gland
Secretes thyroxine, triiodothyronine, and calcitonin; positioned in the anterior neck, just inferior to the larynx
T3 - triiodothyronine
Hormone released by thyroid which controls homeostasis of cellular metabolism
T4 - Thyroxine
Hormone secreted by the thyroid
Calcitonin
Decreases blood calcium, carries calcium from blood into storage within bones
Metabolism
Regulated by thyroid hormones, set of life sustaining chemical transformations within the cells of living organisms. Allow growth, reproduction, maintenance of structures and respond to environment.
Parathyroid glands
Located on the posterior thyroid gland, secretes PTH (parathyroid hormone)
PTH (parathyroid hormone)
Increases blood calcium, carries calcium from storage within bones to the blood
Adrenal gland
Located on the superior aspect of the kidneys, each has 2 glands within the cortex and medulla
Adrenal cortex
Outermost portion of the adrenal gland with 3 cell layers that secrete “corticoids” (aldosterone, cortisol, androgen)
Corticoids
Hormones from the adrenal cortex
Aldosterone, cortisol, androgen
Aldosterone
Mineral cortoids
Cortisol
Glucocorticoids
Androgen
Sex hormones (both male and female)
Adrenal medulla
Innermost portion of the adrenal gland, secretes the “fight or flight” hormones
Adrenaline/epinephrine/norepinephrine
Related hormones secreted by the adrenal gland, “fight or flight” hormones
Pancreas
Controls homeostasis of blood glucose levels,
Contains pancreatic islets cells or islets of langerhans
Islet cells/islets of langerhans
Specialized hormone producing cells spread throughout the pancreas
Glucose
Produced by alpha cells, glucose from storage to blood.
Insulin
Produced by beta cells, glucose from blood to storage
Ovaries
Primary female sex glands that produce two hormones, estrogen and progesterone
Estrogen
Hormone produced by female developing ovarian follicles, responsible for female characteristics,
Preparation for pregnancy
Progesterone
Hormone produced by the deteriorating corpus luteum,
Preparation for mensturation
Ovarian follicle/Graafian follicle
Fully developed ovarian follicle
Ovulation
Extrusion of an ovum by rupture of a follicle
Testes/testicles
Primary male sex glands found within the scrotum, produce sperm cells, fluid for ejaculate, and testosterone
Testosterone
Hormone produced by male testicles that give male characteristics
Thymus gland
Located in the upper mediastinum containing a cortex and a medulla, composed largely of lymphocytes
Thymosine
A combination of several hormones secreted by the thymus gland, function is development and function of the immune system
Placenta
A temporary endocrine gland, during pregnancy only which produces chorionic gonadotropins and limited production of estrogen and progesterone
Chorionic gonadotropins
Hormone produced by the placenta during pregnancy
Pineal gland
Located near the 3rd ventricle of the brain, responds to sensory input from the eyes.
Aka 3rd eye
Secretes hormone melatonin
Melatonin
Hormone secreted by the pineal gland, makes a person sleepy, increases at night and decreases during the day
Circadian rhythm
Our “body clock” of sleep and wake cycle, controlled by the pineal gland
Cholecystokinin
“Bile bladder move”
Small intestine sensors detect presence of fatty food, cholecystokinin released into blood stream, signals gall bladder to contract, bile expelled into small intestine
Osteoporosis
Decreased bone mineral density, usually caused by osteoclast activity surpassing osteoblasts. May also occur with prolonged steroidal use or prolonged immobilization of extremities
Radiographic appearance of osteoporosis
Must be severe enough to detect (50-70% loss) on plain film. Can be diagnosed by DEXA (bone densitometry) or QCT (quantative computerized tomography)
Osteomalacia
Failure of bony calcification, insufficient mineralization of adult skeleton after closure of the epiphyseal plates.
Radiographic appearance of osteomalacia
Loss of bone density, thinning of cortical bone, deossification of medullary cavity. Maybe bent due to stress and loss of minerals (most often pelvis, vertebrae, thorax, and proximal extremities)
Paget’s disease/osteitis deformans
Metabolic disorder of unknown etiology, destruction occurs first followed by repair which results in weak, deformed, thickened bone that fractures easily. Usually occurs in mid life and occurs in men 2 times more than women
Radiographic appearance of Paget’s
Pelvis most common and initial site of manifestation, increase of bone along the iliac bone margins, thickens pelvic brim. Long bone destruction starts at one end and extends along the shaft and usually ends in a well defined v-shaped pattern. Upon repair bone is enlarged and wide cortex bone.
Acromegaly
Disturbance of the pituitary gland, most commonly adenoma, excessive secretion of HGH, bones in adult skeleton can no longer grow in length this grow thicker and denser
Radiographic appearance of acromegaly
Thicker and dense bone. Prominent forehead and jaw, widened teeth, large hands, coarse facial features
Gigantism
Hyper secretions of growth hormone from anterior pituitary gland during adolescence
Radiographic appearance of gigantism
Long bones due to hyper secretion of skeleton not at skeletal maturity when epiphyseal plates still open
Diabetes insipidus
Neurogenic in origin, deficiency of vasopressin, posterior pituitary, insufficient levels of ADH - antidiuretic hormone, treated with hormone replacement therapy
Polydipsia
Abnormally great thirst - a symptom of diabetes insipidus
Polyuria
Abnormally great urination - a symptom of diabetes insipidus
Cushing’s syndrome/hypercorticolism
Excessive adrenal cortex hormones, hyper secretion of glucocorticoid from adrenal cortex
Signs/symptoms of Cushing’s syndrome
Thinning of skin, moon face, obesity above waist, reddish rounded face, buffalo hump, slow growth in children, skin infections and acne, easy bruising, purplish marks similar to the appearance if stretch marks
Hirsutism
Excessive hair growth, a symptom of female patients with Cushing’s syndrome have along with increased androgen and irregular menstural cycles
Addison’s disease/hypercorticolism
Insufficient adrenal cortex hormones due to autoimmune, infection, neoplasm, hemorrhage,.
Insufficient cortisol, aldosterone, and androgen
Diabetes Mellitus
Types 1 & 2, chronic hyperglycemia
Type 1 - juvenile diabetes
Autoimmune destruction of pancreatic beta cells, no insulin produced
Signs and symptoms of type 1 juvenile diabetes
Weight loss, fluctuating blood glucose, polydipsia/polyuria, increased appetite, ketoacidosis, circulatory disorders
Type 1 Juvenile Diabetes is treated by
Insulin, glucose monitoring
Type 2 Adult onset diabetes
Insulin resistance and inadequate secretion of insulin
Signs and symptoms of type 2 adult onset diabetes
Deceased circulation, deceased neurological response, specifically into lower extremities, can result in ulcers, infection, gangrene, and even amputation
Type 2 adult onset diabetes is treated by
Oral antihyperglycemics, weight loss, exercise
Graves’ disease/hyperthyroidism
Excessive production of TSH, autoimmune thyroiditis, hyperthyroidism
Signs/symptoms of Graves’ disease
Enlarged thyroid gland, goiter, changes to eyes and skin, hyperactivity, nervousness, weight loss
Hashimotos disease/hypothyroidism
Insufficient production of TSH, autoimmune thyroiditic, hypothyroid
Signs and symptoms of hashimotos disease
Decreased energy, cold intolerance, personality changes, modest weight gain, brittle nails, constipation, depression, puffy eyes
Cretinism
Congenital hypothyroidism which results in growth retardation, developmental delays, and other abnormal features
Goiter
Mass around the neck/thyroid
Cause is thought to be iodine deficiency
Exophthalmos
Bulging of the eyes
Hyperparathyroidism
Over activity of parathyroid glands resulting in excess production of parathyroid hormone
Signs and symptoms of hyperparathyroidism
Fatigue/weakness, anorexia, weight loss, polydipsia/polyuria, pancreatitis, peptic ulcers, gout, osteopenia
Nephrocalcinosis
Disturbance of calcium metabolism within the renal parenchyma
