Endocrine System Allied Health Sciences 1 Mrs. Lewis

Endocrine Endocrine SystemSystem

Allied Health Sciences 1Allied Health Sciences 1

Mrs. LewisMrs. Lewis

GlandsGlands

Endocrine GlandsEndocrine Glands Secretes hormones directly into Secretes hormones directly into

bloodstreambloodstream Ductless Ductless

Exocrine GlandsExocrine Glands Secrete substances through a duct Secrete substances through a duct

(sweat, salivary, lacrimal and pancreas)(sweat, salivary, lacrimal and pancreas)

Function of the Endocrine Function of the Endocrine SystemSystem

To secrete substances (hormones- To secrete substances (hormones- chemical messengers that chemical messengers that coordinate and direct target cells coordinate and direct target cells and organs). and organs).

Hormonal ControlHormonal Control

Negative FeedbackNegative Feedback Drop in hormone level triggers a chain Drop in hormone level triggers a chain

reaction to increase secretion, for reaction to increase secretion, for example:example:

1.1. Blood level of hormone fallsBlood level of hormone falls

2.2. Brain gets message and sends out Brain gets message and sends out hormone to stimulate glandhormone to stimulate gland

3.3. Gland stimulates more hormoneGland stimulates more hormone

4.4. When blood levels of hormone increase, When blood levels of hormone increase, the brain hormones stop the brain hormones stop

Pituitary GlandPituitary Gland Tiny structure the size of a grapeTiny structure the size of a grape Located at the base of the brain (cranial cavity)Located at the base of the brain (cranial cavity) Connected to the hypothalamusConnected to the hypothalamus Divided into anterior and posterior lobesDivided into anterior and posterior lobes The “Master Gland”The “Master Gland” Pituitary-Hypothalamus InteractionPituitary-Hypothalamus Interaction

Releases hormones from the anterior pituitary are controlled by Releases hormones from the anterior pituitary are controlled by “releasing factors” from the hypothalamus“releasing factors” from the hypothalamus

While hypothalamus is part of the nervous system, it produces two While hypothalamus is part of the nervous system, it produces two hormones that are stored in the posterior pituitaryhormones that are stored in the posterior pituitary

Anterior Pituitary LobeAnterior Pituitary Lobe Growth hormone- responsible for growth and developmentGrowth hormone- responsible for growth and development Prolactin- develops breast tissue, stimulates production of milk after Prolactin- develops breast tissue, stimulates production of milk after

childbirth- produced by the pituitary gland.childbirth- produced by the pituitary gland. Thyroid-Stimulating Hormone-acts on the thyroid glandThyroid-Stimulating Hormone-acts on the thyroid gland Follicle-Stimulating Hormone- stimulates growth of graafian follicle Follicle-Stimulating Hormone- stimulates growth of graafian follicle

to grow in the ovary and production of estrogen in females, sperm in to grow in the ovary and production of estrogen in females, sperm in males.males.

Luteinizing Hormone- stimulates ovulation and formation of corpus Luteinizing Hormone- stimulates ovulation and formation of corpus luteum, which produces progesterone in females.luteum, which produces progesterone in females.

FSH and LH are pituitary hormones that act on the ovaries and FSH and LH are pituitary hormones that act on the ovaries and testes.testes.

Posterior Pituitary LobePosterior Pituitary Lobe

Vasopressin- converts to ADH Vasopressin- converts to ADH (antidiuretic hormone) in the (antidiuretic hormone) in the bloodstream, acts on kidney to bloodstream, acts on kidney to concentrate urine and preserve H20 concentrate urine and preserve H20 in the body.in the body.

Oxytocin- released during childbirth Oxytocin- released during childbirth causing contractions in the uterus causing contractions in the uterus and can be given to induce labor and can be given to induce labor (Pitocin).(Pitocin).

Thyroid GlandThyroid Gland

Butterfly-shaped mass of tissueButterfly-shaped mass of tissue On either side of the larynx, over tracheaOn either side of the larynx, over trachea H-shapedH-shaped Main hormone- Thyroxine is controlled by Main hormone- Thyroxine is controlled by

the secretion of TSH.the secretion of TSH. Thyroxine controls the rate of metabolism, Thyroxine controls the rate of metabolism,

stimulates cellular metabolismstimulates cellular metabolism Calcitonin- controls calcium ion Calcitonin- controls calcium ion

concentration in the body, prevents concentration in the body, prevents hypercalcemia. hypercalcemia.

Parathyroid GlandsParathyroid Glands

Four glands, each the size of a grain Four glands, each the size of a grain of riceof rice

Attached to posterior thyroid in the Attached to posterior thyroid in the neckneck

Produce parathormone which helps Produce parathormone which helps control blood calcium level, prevents control blood calcium level, prevents hypocalcemia. Tends to increase the hypocalcemia. Tends to increase the concentration of calcium in the concentration of calcium in the blood.blood.

ThymusThymus

Endocrine gland and lymphatic Endocrine gland and lymphatic organorgan

Located behind the sternum, above Located behind the sternum, above and in front of the heart- thoracic and in front of the heart- thoracic cavitycavity

Begins to disappear at pubertyBegins to disappear at puberty

Adrenal GlandsAdrenal Glands Located on top of each kidneyLocated on top of each kidney Adrenal cortex secretes hormones known Adrenal cortex secretes hormones known

at corticoids- they are anti-inflammatoryat corticoids- they are anti-inflammatory They are: mineral corticoids, They are: mineral corticoids,

glucocorticoids, and sex hormonesglucocorticoids, and sex hormones Androgens are male sex hormonesAndrogens are male sex hormones Adrenal medulla secretes epinephrine Adrenal medulla secretes epinephrine

(adrenalin) and norepinephrine(adrenalin) and norepinephrine Adrenalin is a powerful cardiac stimulent- Adrenalin is a powerful cardiac stimulent-

“fight or flight” hormones that prepare “fight or flight” hormones that prepare the body for an emergency situation. the body for an emergency situation. Response to stress. Response to stress.

GonadsGonads

Located in the pelvic cavityLocated in the pelvic cavity Ovary in a femaleOvary in a female Testes in maleTestes in male Estrogen- development of female Estrogen- development of female

reproductive organs secondary sex reproductive organs secondary sex characteristics.characteristics.

Progesterone- plays a part in the menstrual Progesterone- plays a part in the menstrual cyclecycle

Testosterone- male reproductive organs Testosterone- male reproductive organs and secondary sex characteristics.and secondary sex characteristics.

PancreasPancreas Located behind the stomach- abdominal cavityLocated behind the stomach- abdominal cavity Endocrine and exocrine functionsEndocrine and exocrine functions Involved in production of insulin by islets of Involved in production of insulin by islets of

langerhans, endocrine portion of the pancreas.langerhans, endocrine portion of the pancreas. Insulin- promotes utilization of glucose by the Insulin- promotes utilization of glucose by the

cells, fatty acid and amino acid transport, and cells, fatty acid and amino acid transport, and facilitates protein synthesis, secretes the most facilitates protein synthesis, secretes the most insulin after meals. Insulin acts to lower blood insulin after meals. Insulin acts to lower blood sugar levels. sugar levels.

Other cells in islets of langerhans secrete Other cells in islets of langerhans secrete glucagon, action may opposite that of glucose glucagon, action may opposite that of glucose (increase glucose in bloodstream).(increase glucose in bloodstream).

Pineal GlandsPineal Glands

Located in 3Located in 3rdrd ventricle in brain, ventricle in brain, produces melatonin.produces melatonin.

Another HormoneAnother Hormone Prostaglandins- tissue hormones, Prostaglandins- tissue hormones,

can cause constriction of blood can cause constriction of blood vessels, muscle contractions. Can be vessels, muscle contractions. Can be used to induce labor. used to induce labor.

Endocrine Disorders Endocrine Disorders GigantismGigantism

Hyperfunction of the pituitary-too much growth Hyperfunction of the pituitary-too much growth hormone.hormone.

In preadolescent- overgrowth of long bones In preadolescent- overgrowth of long bones leads to excessive tallnessleads to excessive tallness

AcromegalyAcromegaly Hyperfunction of pituitary-too much growth Hyperfunction of pituitary-too much growth

hormone in adulthood.hormone in adulthood. Overdevelopment of bones in face, hands, Overdevelopment of bones in face, hands,

joints, and feet.joints, and feet. Attacks cartilage- so the chin protrudes, lips Attacks cartilage- so the chin protrudes, lips

nose and extremities enlarge.nose and extremities enlarge. Rx= drugs to inhibit growth hormone, radiationRx= drugs to inhibit growth hormone, radiation

Endocrine Disorders Endocrine Disorders continued…continued…

DwarfismDwarfism Hypofunction of pituitary in childhoodHypofunction of pituitary in childhood Small size, but body proportions and intellect are normalSmall size, but body proportions and intellect are normal Sexual immaturity Sexual immaturity Rx- early diagnosis, injection of growth hormoneRx- early diagnosis, injection of growth hormone

Diabetes InsipidusDiabetes Insipidus Drop in amount of ADH from posterior pituitary, excessive loss of Drop in amount of ADH from posterior pituitary, excessive loss of

waterwater Symptoms- polyuria and polydipsiaSymptoms- polyuria and polydipsia

HyperthyroidismHyperthyroidism Overactive thyroid glandOveractive thyroid gland Too much thyroxin secreted leading to enlargement of glandToo much thyroxin secreted leading to enlargement of gland People with this disease consume large quantities of food but lose People with this disease consume large quantities of food but lose

body fat and weightbody fat and weight Most pronounced symptoms are enlargement of glad (goiter) and Most pronounced symptoms are enlargement of glad (goiter) and

bulging of eyeballs (exophthalmos) bulging of eyeballs (exophthalmos) Simple goiter is caused by low dietary intake of iodine.Simple goiter is caused by low dietary intake of iodine. Symptoms- nervous irritability. Fatigue is not a symptom.Symptoms- nervous irritability. Fatigue is not a symptom. Rx= total or partial removal of thyroid gland, drugs to reduce Rx= total or partial removal of thyroid gland, drugs to reduce

thyroxin, radiation.thyroxin, radiation.


HypothyroidismHypothyroidism Not enough thyroxine secretedNot enough thyroxine secreted May be due to lack of iodine (simple goiter)May be due to lack of iodine (simple goiter) Major cause of other types of inflammation of thyroid which Major cause of other types of inflammation of thyroid which

destroys the ability of the gland to make thyroxinedestroys the ability of the gland to make thyroxine Symptoms- dry and itchy skin, dry and brittle hair, constipation, Symptoms- dry and itchy skin, dry and brittle hair, constipation,

muscle cramps at nightmuscle cramps at night MyxedemaMyxedema

Hypothyroidism in adultsHypothyroidism in adults Face gets swollen, weight increasesFace gets swollen, weight increases Rx= daily medication of thyroxineRx= daily medication of thyroxine

CretinismCretinism Hypothyroidism in early infancy or childhoodHypothyroidism in early infancy or childhood Lack of mental and physical growth causes mental retardation Lack of mental and physical growth causes mental retardation

and very small statureand very small stature Rx= thyroid extract- damage cannot be undone but treatment Rx= thyroid extract- damage cannot be undone but treatment

can halt progressioncan halt progression


TetanyTetany Accidental removal of the parathyroid glands could cause Accidental removal of the parathyroid glands could cause

tetany.tetany. In hypoparathyroidism, decreased calcium levels affect In hypoparathyroidism, decreased calcium levels affect

function of nervesfunction of nerves Convulsive twitching develops, person dies of spasms in the Convulsive twitching develops, person dies of spasms in the

respiratory musclesrespiratory muscles Rx= Vitamin D, calcium and parathormoneRx= Vitamin D, calcium and parathormone

Cushing’s SyndromeCushing’s Syndrome Blood sugar levels go up Blood sugar levels go up Hypersecretion of adrenal cortexHypersecretion of adrenal cortex May be caused by adrenal cortical tumor or prolonged use of May be caused by adrenal cortical tumor or prolonged use of

prednisoneprednisone Symptoms- high blood pressure, muscle weakness, obesity, Symptoms- high blood pressure, muscle weakness, obesity,

poor healing, tendency to bruise, hirsutism (excessive hair poor healing, tendency to bruise, hirsutism (excessive hair growth), menstrual disordersgrowth), menstrual disorders

Rounded moon face and buffalo humpRounded moon face and buffalo hump Rx- surgical removal of tumorRx- surgical removal of tumor


Addison’s DiseaseAddison’s Disease Hypofunction of adrenal cortexHypofunction of adrenal cortex Symptoms- bronzing of skin, hypoglycemia, Symptoms- bronzing of skin, hypoglycemia,

hypotension, etc.hypotension, etc. Rx- replace deficient hormonesRx- replace deficient hormones

Steroid Abuse in SportsSteroid Abuse in Sports Anabolic steroids (androgens) can help build Anabolic steroids (androgens) can help build

bigger, stronger musclesbigger, stronger muscles Risks far outweigh temporary improvements- Risks far outweigh temporary improvements-

males have liver changes, atrophy of testicles, males have liver changes, atrophy of testicles, breast enlargement, and cardiovascular diseasebreast enlargement, and cardiovascular disease

Female risks include amenorrhea, abnormal Female risks include amenorrhea, abnormal placement of body hair, baldness, voice changesplacement of body hair, baldness, voice changes


Diabetes MellitusDiabetes Mellitus Caused by decreased secretion of insulinCaused by decreased secretion of insulin can be insulin dependent (juvenile) or non-insulin can be insulin dependent (juvenile) or non-insulin

dependentdependent Symptoms- polyuria, polyphagia, polydypsia, weight loss, Symptoms- polyuria, polyphagia, polydypsia, weight loss,

blurred vision, and possible diabetic comablurred vision, and possible diabetic coma If not treated, excess glucose in the blood (hyperglycemia) If not treated, excess glucose in the blood (hyperglycemia)

and glucose secreted in urine (glycosuria).and glucose secreted in urine (glycosuria). Since glucose not available for cellular oxidation, body Since glucose not available for cellular oxidation, body

starts to burn up protein and fatstarts to burn up protein and fat If too much insulin is given, blood sugar may go too low If too much insulin is given, blood sugar may go too low

(hypoglycemia->insulin shock)(hypoglycemia->insulin shock) If blood sugar gets too high- hyperglycemia->lack of insulin If blood sugar gets too high- hyperglycemia->lack of insulin

or a diabetic coma.or a diabetic coma. Type II (non-insulin dependent) is most common, usually Type II (non-insulin dependent) is most common, usually

familial, occurs later in life, control with oral hypoglycemic familial, occurs later in life, control with oral hypoglycemic drugs and dietdrugs and diet

Test for diabetes- blood sample measured in glucometer- Test for diabetes- blood sample measured in glucometer- done by patient in home- normal blood sugar 80-100mg.done by patient in home- normal blood sugar 80-100mg.


Seasonal Affective DisorderSeasonal Affective Disorder Also called “cabin fever”, “winter blues” Also called “cabin fever”, “winter blues”

or “sunshine disorder”.or “sunshine disorder”. Depression or anxiety people feel Depression or anxiety people feel

during dark days of winterduring dark days of winter Cause may be due to increase in Cause may be due to increase in

melatonin from pineal glandmelatonin from pineal gland Rx- sunshineRx- sunshine

The End!!!!The End!!!!

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Endocrine System Allied Health Sciences 1 Mrs. Lewis