Exercise and Hormone Function Flashcards
Endocrine System
- second messenger system of the body
2. uses chemical messages (hormones) that are released into the blood
what do hormones control
- reproduction
- growth and development
- mobilization of body defenses
- maintenance of homeostasis
- regulation of metabolism
where are hormones secreted into
extracellular fluids
how are hormones delivered to target sites?
they bind to a protein in the blood in ordered to be transferred to their specific target sites
what is the role of cyclic AMP
secondary messenger
-it does the hormones job without the hormone entering the cell
what glands are activated to release hormones by the anterior pituitary gland
- thyroid gland
- adrenal cortex
- gonad (testis)
when there is a low concentration of Ca, what does this stimulate
stimulates the parathyroid glands and it secretes the parathyroid hormone (PTH)
-this hormone then proceeds to go to the bone which causes the osteoclasts to break down the bone to release Ca into the blood
what occurs when the blood Ca levels are too high
- thyroid gland releases calcitonin
- Calcitonin goes to the bones and to the kidney
- In the bone, it prevents osteoclasts from breaking down the bone
- in the kidney, it prevents the re-absorption of Ca which results in excretion through urine
list the 10 major endocrine organs
- pineal gland
- hypothalamus
- pituitary gland
- thyroid gland
- parathyroid gland
- thymus gland
- adrenal glands
- pancreas
- ovary
- Testis
Pituitary Gland
- size of a grape
- hangs from the hypothalamus
- protected by the sphenoid bone
- has 2 functional lobes
1. anterior pituitary-glandular tissue
2. posterior pituitary-nervous tissue
how many anterior pituitary hormones are there
6
- 2 affect non endocrine targets
- 4 stimulate other endocrine glands (tropic hormones)
what are the 6 hormones released by the anterior pituitary gland
- growth hormone—>bones and muscles
- Prolactin (PRL)—>mammary glands
- Follicle stimulating hormone (FSH)—> testes or ovaries
- luteinizing hormone (LH)—>testes or ovaries
- thyrotropic hormone (TSH)—>thyroid
- adrenocorticotropic hormone (ACTH)—>adrenal cortex
- what does ADH stand for
- what is another name for it
- what does it do
- antidirretic
- vasopression
- regulates water in the body
what 2 hormones does the posterior pituitary gland release
- ADH—>kidney tubules
2. Oxytocin—>mammary glands & uterine muscles
Hormones of the adrenal Medulla
Catecholamines 1. epinephrine 2. Norepinephrine These two are carried by albumin these prepare the body to deal with short term stress
give an example of mineralocorticoids
aldosterone: sodium re-absorption in kidneys
pancreatic Islets
islets of the pancreas produce hormones
- insulin allows glucose to cross plasma membranes into cells from beta cells
- glucagon allows glucose to enter the blood from alpha cells
*these hormones are antagonists that maintain blood sugar homeostasis
Estrogens
- what are the produced by
- what do they stimulate
- other functions
- produced by the graafian follicles or the placenta
- stimulates the development of secondary female characteristics
Other functions
- matures female reproductive organs
- helps prepare the uterus to receive a fertilized egg
- helps maintain pregnancy
- prepares the breasts to produce milk
Progesterone
produced by the corpus luteum
- acts with estrogen to bring about the menstrual cycle
- helps in the implementation of an embryo in the uterus
what are 2 hormones produced by the ovaries
estrogen and progesterone
what cells in the testes are hormone producing
interstitial cells
what do the interstitial cells of the testes produce
several types of androgens
1. testosterone is the most important
what is testosterone do
- responsible for adult male secondary sex characteristics
- promotes growth and maturation of male reproductive system
- required for sperm cell production
define down regulation
decreased numbers of cell receptors, less hormone can bind to the cell and higher concentrations of the hormone remain in the blood plasma
define up regulation
increased number of cell receptors, more hormone can bind to the cell and lower concentrations of the hormone remain in the blood plasma
hormonal adaptation
1. Resting concentrations
resting concentrations are generally less
Acute Effects of endurance training in the anterior pituitary
- endorphins
- prolactin
- somatotropin
- endorphins increase with long duration exercise
- prolactin increases with intensity
- somatotropin increases with moderate intensity
acute effects of endurance training in the posterior pituitary
1. vasopressin (ADH)
increases with intensity
acute effects of endurance training in the adrenal cortex
- aldosterone
- cortisol
- aldosterone increases with intensity
2. cortisol increases 60-90% of VO2 max also increases with intensity and duration
acute effects of endurance training in the adrenal medulla
- norepinephrine
- epinephrine
- norepinephrine increases 50-60% of VO2 max, increases with intensity
- epinephrine is parallel to norepinephrine but less
acute effects of endurance training in the thyroid
- triiodothyronine (T3)
- thyroxine (T4)
- triiodothyronine increases with intensity
2. thyroxine increases with intensity
acute effects of endurance training in the pancreas
- glucagon
- insulin
- glucagon 1-2 hours after onset of exercise
2. insulin decreases 50% of VO2 max
acute effects of endurance training in the parathyroid
1. parathormone
- increases with long duration exercise
acute effects of endurance training in the ovaries
- estrogen
- progesterone
- estrogen increases with exercise
2. progesterone increases with exercise
acute effects of endurance training in the testes
1. testosterone
- testosterone increases with exercise
acute effects of endurance training in the kidney
1. renin
- increases with intensity
chronic effects with endurance training in the hypothalamus-pituitary hormones
- ACTH
- Endorphin
- FS/LH
- Estrogen
- Testosterone
- Somatotropin
- ACTH increases
- endorphin decreases
- FS/LH decreases
- estrogen decreases
- testosterone decreases UNLESS you are a resistance trained male it increases
- somatotropin has no change at rest but decreases during exercise
chronic effects of endurance training in the thyroid hormones
- triiodothyronine (T3)
- thyroxine
- triiodothyronine decreases, increased turnover
2. thyroxine (T4) decreases, increased turnover
what 2 hormones raise the overall body metabolism and need iodine to be activated
- triiodothyronine
2. thryoxine
chronic effects of endurance training in the adrenal hormones
- cortisol
- norepinephrine
- epinephrine
- cortisol increases slightly
- norepinephrine decreases
- epinephrine decreases
chronic effects of endurance training in the pancreatic hormones
- glucagon
- insulin
- glucagon decreases
2. insulin decreases