endocrine system. structures group of ductless glands that secrete substances directly into the...

ENDOCRINE SYSTEM

STRUCTURES

Group of ductless glands that secrete substances directly into the blood stream.

Substances are known as hormones Hormones are substances that are frequently referred to as

“chemical messengers” that stimulate many functions through out the body.

Functions include: Stimulate exocrine glands, stimulate other endocrine glands, Regulate growth and development, Regulate metabolism, Maintain fluid and chemical balance, Control various sex processes

STRUCTURES

Pituitary Gland Often called master gland because it produces many hormones

that affect other glands.

Located at the base of the brain

Separated into two lobes both secrete different hormones Anterior Lobe: Somatotropin-Growth Hormone, Follicle

Stimulating/Luteinizing- Ovulation/Sperm production, Prolactin-production of milk, Melanocyte Stimulating- Stimulates production and dispersion of melanin pigment in the skin

Posterior Lobe-Vasopressin-antidiuretic, promotes reabsorption of water in the kidneys and constricts vessels, Oxytocin-Causes contraction of uterus during childbirth, stimulates milk flow from the breast

PITUITARY GLAND

STRUCTURES

Thyroid Gland Sits on anterior aspect of trachea

Secretes: Thyroxine-stimulates metabolic rate, physical and mental growth, regulates metabolism of carbohydrates, proteins and fats, Calcitonin- absorption of calcium by the bones and lowers blood calcium levels

THYROID GLAND

STRUCTURES

Parathyroid Gland Sits on top of thyroid gland

Secretes-Parathormone-Regulates the amount of calcium and phosphate in the blood, stimulates kidneys to conserve blood calcium, stimulates calcium absorption in the small intestine

PARATHYROID GLAND

STRUCTURES

Adrenal Gland Sits on top of both kidneys

Secretes-Mineralocorticoids-reabsorption of sodium, potassium and water in the kidneys, Glucocorticoids-metabolism of nutrients, increase blood glucose levels, reduce stress and anti-inflammatory, Gonadocorticoids-stimulates either male or female sexual characteristics, Epinephrine-stimulates sympathetic nervous system, fight or flight response, Norepinephrine- Fight or flight response

ADRENAL GLAND

STRUCTURES

Pancreas Sits below stomach in upper left quadrant

Secretes: Insulin-Metabolism of glucose, promotes fatty and amino acid transport into cells, Glucagon-Maintains blood level of glucose by stimulating the liver to release stored glycogen

PANCREAS

STRUCTURES

Ovaries Found in women sit deep inside the body cavity at the top of the

uterus

Secrete: Estrogen-promotes growth and development of sex organs, Progesterone-Maintains lining of the uterus

OVARIES

STRUCTURES

Testes Found in males located in the scrotum that hangs from the body

Secretes: Testosterone-Stimulates growth of male sex organs and maturation of sperm

TESTES

STRUCTURES

Thymus Sits center of chest in children

Disappears during puberty

Secretes: Thymosin-stimulates production of lymphocytes and antibodies in early life

THYMUS

STRUCTURES

Pineal Located in brain

Secretes: Melatonin-may delay puberty by inhibiting gonadotropin, may regulate sleep/wake cycles, Serotonin-may prevent vasoconstriction in the brain, inhibits gastric secreations

PINEAL GLAND

DISEASES AND CONDITIONS

Acromegaly

Over secretion of somatotropin causes a benign tumor on the pituitary gland.

Bones of the hands, feet and face enlarge, skin and tongue thickens causing slurred speech

Treatment is surgical removal of tumor or radiation, however tumor usually returns

Shortens life expectancy

DISEASE AND CONDITIONS

Gigantism Over secretion of somatotropin

before puberty

Excessive growth of long bones, extreme tallness, decreased sexual development

DISEASES AND CONDITIONS

Diabetes Insipidus Decreased secretion of

vasopressin

Results in water failing to be reabsorbed by the kidneys

Increases urination, excessive thirst, dehydration, weakness, constipation and dry skin

Administer ADH to correct

DISEASES AND CONDITIONS

Dwarfism Under secretion of somatotropin

and can be causes by a tumor, infection genetic factors or injury

Small body size, short extremities, lack of sexual development

Can be treated if caught early with injections.

DISEASES AND CONDITIONS

Goiter Enlargement of the Thyroid Gland

Causes: hyperactive thyroid, iodine deficiency, tumor, over secretion of thyroid stimulating hormone in the pituitary gland

Thyroid enlargement, difficulty swallowing, cough, choking sensation

Treatment is to eliminate the cause

DISEASES OR CONDITIONS

Hyperthyroidism Over activity of the thyroid gland

which increases BMR

Symptoms: extreme nervousness, tremors, irritability, rapid pulse, excessive sweating, heat intolerance

Treatment: radiation or surgical intervention

DISEASES AND CONDITIONS

Hypothyroidism Under activity of the thyroid gland

Two types Cretinism or Myxedema

Symptoms: course dry skin, slow mental function, fatigue, weakness, intolerance to cold, weight gain, edema, puffy eyes, slow pulse

DISEASES AND CONDITIONS

Graves Disease Extreme form of hyperthyroidism

More common in women than men

Symptoms include: strained tense facial expressions, protruding eyeballs, goiter, emotional instability, tachycardia, tremendous appetite with weight loss

Treatment: medication, radiation and surgical removal

DISEASES AND CONDITIONS

Hyperparathyroidism-over production of parathormone due most often to tumor

Symptoms: excessive calcium in blood, kidney stones, lethargy, gastrointestinal issues, calcium deposits in vessels and organs

Treatment: Removal of tumor, removal of glands, diuretics, low calcium diet

DISEASES AND CONDITIONS

Hypoparathyroidism-Underactivity of the parathyroid, causes low levels of calcium in the blood.

Symptoms: Constant contraction of muscles, hyperirritability of nervous system, twitching possible death

Treatment: Supplement calcium and vitamin d, surgical removal of parathyroid glands

DISEASES AND CONDITIONS

Addison’s Disease-decreased secretion of aldosterone by adrenal glands, interferes with reabsorption of sodium and water resulting in high potassium levels in the blood

Symptoms: dehydration, diarrhea, fatigue, hypotension, mental lethargy, weight loss, excessive pigmentation (bronzing of the skin)

Treatment: corticosteroids, control sodium intake, fluid regulation

DISEASES AND CONDITIONS

Cushing’s Disease-Over secretion of glucocorticoids from the adrenal glands, caused by tumor or pituitary gland defect

Symptoms: hyperglycemia, hypertension, excessive hair growth, poor wound healing, A “moon” face, obesity

Treatment: removal of tumor/glands, hormone replacement therapy

DISEASES AND CONDITIONS

Treatment: None for Type 1, just manage symptoms through insulin, Type 2 is about weight control and exercise as well as diet corrections

Diabetes Mellitus-chronic disease caused by decreased secretion of insulin

Two types: Type 1 (insulin dependent) occurs early in life, more severe and requires insulin, Type 2 (non-insulin dependent) occurs later in life, not a severe, diet restriction

Symptoms: hyperglycemia, frequent urination, excessive thirst, sugar in urine, weight loss, slow healing skin infections, vision changes