Endocrine System Flashcards
Endocrine System contains
- pituitary gland
- thyroid gland
- parathyroid
- adrenal gland
- pancreas
- pineal and thymus glands
- ovaries and testes (part of reproductive and endocrine system)
Endocrine System: Structure and Function
- consisting of endocrine (ductless) glands
- secretion of chemicals called hormones directly into the bloodstream
- control and integration of many bodily functions
- action of hormones on target organs to increase or decrease the targets activity level; faster heart rate, sweaty palms when nervous
- monitoring and interpretation of and reaction to changes in the body and external environment to maintain homeostasis
Pituitary gland (hypophysis)
Tiny, pea-shaped structure at the base of the brain
- consists of an anterior and posterior lobe
- regulation of many body activities
- stimulation of other glands to secrete their own specific hormones
- effects of its hormones felt throughout the body
- produces many different hormones which effect different body systems
Anterior Pituitary (Anterior lobe)
Secretion of six hormones: 1. Adrenocorticotrophic hormone (ACTH) 2. Thyroid-stimulating hormone (TSH) 3. Luteinizing hormone (LH) 4. Follicle-stimulating hormone (FSH) 5. Prolactin (PRL) 6. Growth Hormone (GH) also melanocyte-stimulating hormone (MSH)
Adrenocorticotrophic Hormone (ACTH)
regulates the production of steroid hormones by the adrenal gland
(anterior pituitary lobe)
Follicle-stimulating Hormone (FSH)
stimulates egg production in the ovaries or sperm production in the testes
(anterior pituitary lobe)
Growth Hormone (GH)
also called somatotropin, which regulates growth of bones and other tissue
(anterior pituitary lobe)
Luteinizing Hormone (LH)
stimulates the production of sex hormones by the ovaries or testes
(anterior pituitary lobe)
Prolactin (PRL)
stimulates growth of breast tissue and milk production in females
(anterior pituitary lobe)
Thyroid-stimulating Hormone (TSH)
regulates activity of the thyroid gland
anterior pituitary lobe
Posterior Pituitary (Posterior lobe)
(neurohypophysis)
Secretion of two hormones:
1. Antidiuretic Hormone (ADH)
2. Oxytocin
Antidiuretic Hormone (ADH)
also called vasopressin, -regulation of urinary output -role in blood pressure regulation (posterior pituitary gland) anti- against diuretic- urination
Oxytocin
-inducement of labor in pregnant women by stimulating contractions in the uterus
-promotion of milk secretion from the mammary glands
(posterior pituitary lobe)
Thyroid Gland
Two lobes on either side of the Trachea (butterfly shaped organ) Secretion of three hormones: 1. Calcitonin 2. Triiodothyronine (T3) 3. Thyroxine (T4)
Calcitonin
regulates normal blood levels of calcium and phosphate (in conjunction with parathyroid hormone)
(Thyroid gland hormone)
Triiodothyronine (T3)
increases the rate of cellular metabolism
Thyroid gland hormone
Thyroxine (T4)
increases the rate of cellular metabolism after being converted to T3 in the tissues
(Thyroid gland hormone)
Parathyroid gland
Two pairs of pea-shaped organs located on the underside of the thyroid gland (yellow ones)
- secretion of parathyroid hormone (PTH)
- regulation of normal blood levels of calcium and phosphate (In conjunction with calcitonin)
Pancreas
Elongated organ located just below the stomach in back of the abdomen
- secretion of two hormones:
1. Insulin
2. Glucagon
Insulin
removes glucose from the blood by promoting storage in tissues as carbohydrates when blood glucose levels are high
(pancreas hormone)
Glucagon
stimulates the release of sugar from storage sites in the liver when blood glucose levels are low
(pancreas hormone)
Pineal gland
Small, pinecone-shaped organ located deep within the brain just behind the thalamus
-secretion of melatonin, influences the maturation of sexual organs during puberty
Thymus gland
Butterfly-shaped organ located between the lungs (right + left lobe)
- withering away during puberty, leaving adults with fat and connective tissue in its place
- secretion of thymosin, which plays a role in development of the immune response in infants
Ovaries
Functioning in the female reproductive and endocrine systems
- secretion of two female sex hormones
1. Estrogen
2. Progesterone
Estrogen (estradiol)
stimulates development of ova (eggs) and secondary sex characteristics
(ovaries hormone)
Progesterone
prepares and maintains the uterus in pregnancy
Testes
Functioning in the male reproductive and endocrine systems
- secretion of male sex hormone testosterone
- responsible for the development of secondary sex characteristics and sex drive
- necessary for sperm production
- maintenance of the reproductive organs in adult males
Graves Disease
caused by oversecretion of hormones (T3 and T4) by the thyroid gland, in which elevated levels produce profound changes in the body’s physiological processes
- more common in woman than men
- most common form of hyperthyroidism
Graves Disease Signs + Symptoms
- exophthalmos
- elevated metabolic rate
- heat intolerance
- weight loss, fatigue, and muscle weakness
- enlarged thyroid (goiter)
- thyrotoxic crisis (storm), including many cardiac manifestations
- tachycardia
- arrhythmias
- heart murmurs
- cardiomegaly
- eyes are likely to protrude
Graces Disease Treatments
depending on patient’s age and severity of the disease
- antithyroid agents to block hormone synthesis within the thyroid gland
- alteration in the structure of the thyroid gland through surgery or radioactive iodine therapy
- beta blockers in combination with one of the treatments listed above
Cushing Syndrome
caused by exposure to excess cortisol
- adrenal or pituitary problem
- long-term use of corticosteroids
- more common in females
Cushing Syndrome Signs + Symptoms
central obesity with thin arms and legs
- fat pad on upper back (buffalo hump)
- round, “moon shaped” face with acne and facial hair
- secondary diabetes due to insulin resistance
- glucose intolerance due to stimulation of gluconeogenesis
- muscle wasting and thin skin with purple striae as a result of cortisol’s catabolic effect on tissues
- Hypokalemia due to sodium retention and potassium loss in the urine
- catabolic effects on bone leading to osteoporosis, pathological fractures, and back pain from compression fractures of the vertebrae
- risk of infection due to anti-inflammatory and immunosuppressive actions of cortisol
- mental status changes in about half of patients , from irritability to psychosis (steroid psychosis)
Cushing Syndrome Treatments
Restoration of cortisol concentration to normal levels
- varied, according to etiology
- restoration of serum concentration of cortisol to normal levels
- surgery or radiation therapy to remove a tumor
- drugs or radiation to suppress adrenocorticotropic hormone (ACTH) secretion
- discontinuing or reducing corticosteroid drug use
- high potassium or low sodium diet
Growth Hormone Imbalance
GH (somatropin) responsible for growth of bones, cartilage, and soft tissue
- synthesized and secreted by the anterior pituitary gland
- Hypersecretion of GH; Two forms:
1. Acromegaly- hypersecretion (excessive) during childhood
2. Gigantism- hypersecretion during childhood - Hyposecretion of GH; One form
1. Dwarfism- hyposecretion (below) during childhood
GH Imbalance Signs + Symptoms: Acromegaly
Hypersecretion of GH during adulthood
- fusion of growth plates at ends of long bones, which prevents person from growing taller
- widening and enlargement of facial features, jaw, hands, and feet
GH Imbalance Signs + Symptoms: Gigantism
Hypersecretion of GH during childhood
- excessive growth of bones and tissues due to high level of GH
- height changes of up tp 6” in 1 year in children
- abrupt development, resulting in abnormally increased height
GH Imbalance Signs + Symptoms: Dwarfism
Hyposecretion of GH during childhood
-lack of growth and short stature but with normal body proportions
GH Imbalance Treatment
Hyposecretion of GH:
-drug therapy with growth hormone
-surgery if a tumor is the cause
Hypersecretion of GH:
-drug therapy to suppress secretion of growth hormone
-surgery to remove an adenoma or radiation therapy to destroy the adenoma
Diabetes Mellitus
Group of metabolic diseases
-characterized by high glucose levels
-caused by defects in insulin secretion, action, or both
Two primary forms:
1. Type 1 (insulin dependent) diabetes mellitus
2. Type 2 (non-insulin dependent) diabetes mellitus
Diabetes Mellitus: Type 1
Insulin dependent diabetes mellitus
- chronic metabolic disorder marked by hyperglycemia
- inability of the pancreas to produce enough insulin to properly control blood glucose levels
- most commonly diagnosed in children, adolescents, or young adults
Diabetes Mellitus: Type 2
non-insulin dependent diabetes mellitus
- gradual onset that occurs in middle age, commonly in overweight patients (because fat interferes with the body’s ability to use insulin)
- characterized by high blood glucose levels that lead to a chronic, lifelong disease that requires medical management
- insulin resistance and inadequate insulin secretion to sustain normal metabolism
Diabetes Mellitus Type 1: Signs +Symptoms
- Fatigue
- Polyphagia (eats a lot), polyuria (urinates a lot), polydipsia (thirsty)
- unplanned weight loss
- blurred vision (hyperglycemic patients with polyphagia)
- diabetic ketoacidosis with loss of metabolic control (during periods of infection or noncompliance with therapy)
Diabetes Mellitus Type 2: Signs + Symptoms
- commonly asymptomatic
- polyphagia, polyuria, polydipsia
- frequent or slow-healing infections
- fatigue
- blurred vision (hyperglycemic patients)
Diabetes Mellitus Type 1: Treatments
- specialized diet and regular exercise
- intensive foot and eye care
- medications, including insulin to lower blood glucose levels
Diabetes Mellitus Type 2: Treatments
- calorie-restricted diet with regular aerobic exercise
- oral drugs
- increase pancreatic secretion of or cellular sensitivity to insulin
- decrease absorption of carbohydrates from the GI tract
- insulin injections
Insulin Injection
rotation of multiple daily injections to several sites
-absorption and effectiveness determined by injection site
Rapid Absorption- abdomen and then upper arm and thigh areas
Slower Absorption- subcutaneous fat and hip and buttock areas
No injection within 2” of the navel
Glucose Testing with a glucometer
monitoring test of glucose levels in the blood (glycemia)
- self-monitoring, usually done before meals and at bedtime
- piercing of skin, typically on the finger, to draw blood
- application of blood to a test strip
Insulin delivery with an insulin pump
- use of a small pump device that delivers subcutaneous insulin
- typically worn on the abdomen or buttocks
- continuous delivery of insulin in small amounts via a tiny catheter with bolus doses added by pushing a button
Hypophysectomy
minimally invasive endoscopic surgery to excise the pituitary gland
- transsphenoidal approach via the nose or just under the upper lip
- possible transfrontal craniotomy (entry though the frontal bone of the skull) to remove a large tumor
