45 terms

Endocrine System

Growth Hormone
Causes protein synthesis & cell growth
Growth Hormone Problems
Too much: gigantism & agromegaly
Too little: growth retardation or dwarfism
Stimulates and maintains milk production
Causes decrease in LH (natural birth control)
Prolactin Problems
Too much: amenorrhea (no mentrual cycle); infertility; breast enlargement
Too little: infertility & lack of milk production (for women); no known effects for men
Adrenocorticotropic Hormone (ACTH)
Stimulates release of cortisol from adrenal gland
Regulates hormone production from adrenal
ACTH Problems
Too much: Cushing's syndrome (weight gain, depression, "moon face," "buffalo hump"
Too little: Addison's disease (severe fatigue; weight loss; lack of recovery from shock)
Thyroid-stimulating Hormone (TSH)
Tells thyroid to make and release thyroid hormone
TSH Problems
Too much: hyperthyroidism; goiter
Too little: hypothyroidism
Follicle-stimulating Hormone (FSH)
Stimulates development of follicles in ovaries (eggs)
Stimulates sperm production in seminiferous tubules
FSH Problems
Too much: usually no problems
Too little: insufficient production of eggs and sperm
Luteinizing Hormone (LH)
Triggers ovulation in females and stimulates corpus luteum to produce progesterone
Stimulates testosteron production by interstitial cells of the testes
LH Problems
Too much: usually no problems
Too little: no ovulation or amenorrhea; low sperm production
Melanocyte-stimulating Hormone (MSH)
Causes color changes in skin (tells melanocytes to make more pigment)
MSH Problems
Too much: more pigmentation
Too little:
Stimulates uterus to produce contractions during childbirth
Causes release of milk for nursing moms
Oxytocin Problems
Too much:
Too little: problems in childbirth; reduced milk production
Antidiuretic Hormone (ADH)
Inhibits urine production
Causes kidney to reabsorb water (keep more water in the body)
ADH Problems
Too much: retain too much water (SIADH)
Too little: diabetes insipidus (excessive production of dilute urine, excessive thirst, dehydration)
Thyroid Hormone (thyroxine)
Regulates metabolism--controls the rate at which glucose is burned
Thyroid Hormone Problems
Goiters--can be due to over or under activity; common cause is lack of iodine
Thyroid Hormone Problems (too much)
Too much: hyperthyroidism (Graves Disease); increased metabolism, hot, increased appetite, weight loss, increased sweating
Thyroid Hormone Problems (too little)
Too little: hypothyroidism (cretinism--in kids; myxedema--in adults); dry skin, lethargy, weakness, cold, low metabolism
Lower blood calcium
Less calcium absorbed in intestines; bones take up more; kidneys get rid of more
Calcitonin Problems
Too much: can be given to people with osteoporosis to help maintain bone density
Too little: not much is known
Parathyroid Hormone (PTH)
More absorbed in intestines; bones "give up" more; kidneys "hold on to" more
Increases blood calcium levels
PTH Problems
Too much: osteoporosis; rickets (bowed legs) in children
Too little: very uncommon; can cause muscle disorders
Aldosterone (mineralocorticoids)
Regulates mineral (salt) levels in blood; controls the salt-water balance; tells kidneys to keep more sodium; causes changes in blood volume and pressure
Aldosterone Problems
Too much: increased blood pressure and edema
Too little: electrolyte and water imbalance
Cortisol (glucocorticoids)
Controls rate of metabolism of carbohydrates; raises blood sugar levels; protects against "long-term" stressors
Cortisol Problems
Too much: Cushing's syndrome (weight gain, depression, "moon face," "buffalo hump"
Too little: Addison's disease (severe fatigue; weight loss; lack of recovery from shock)
Sex Hormones (from adrenal cortex)
Mostly androgens and some estrogens
Hypersecretion: usually masked in men; masculinization in women (bearded ladies)
Epinephrine & Norepinephrine
Raises blood sugar; increases heart rate; increases force of heart contraction; controls blood flow (constricts and dilates blood vessels); "fight-or-flight"; short-term stress response
Epinephrine & Norepinerphine Problems
Too much: rapid heart rate; high blood pressure, sweating, irritability
Too little: Usually not a problem (as long as sympathetic nervous system is OK)
Helps glucose get into cells
Lowers blood glucose levels
Insulin Problems
Too much: very low blood sugar levels
Too little: Diabetes mellitus--excessive thirst, excessive urination, excessive hunger, gluose and ketones in urine
Tells liver to break down glycogen into glucose
Raises blood glucose levels
Glucagon Problems
Too much: no important disorders
Too little: no important disorders
Sleep "trigger"
Helps establish day-night cycles
Responsible for seasonal activiites in other animals
Helps T cells mature
Development of secondary sex characteristics; controls & stimulates reproductive system development & activiites; prepares uterus for fertilized egg; helps maintain pregnancy & prepare breasts to produce milk
Estrogen Problems
Too much:
Too little: infertility; menopause (in women)
Helps maintain pregnancy and prepare breasts to produce milk
Controls and stimulates reproductive system development & activities; development of secondary sex characteristics; needed for continuous production of sperm
Testosterone Problems
Too much: Males--breast development & loss of testes function; Females--deep voice & faicial hair; Both--stunted growth, acne, aggressive behavior
Too little: infertility
Human Chorionic Gonadotropin (hCG)
Stimulates corpus luteum to continue to produce estrogen and progesterone