chapter 18 Flashcards
endocrine system
- consists of
- function
- consists of all endocrine cells and tissues that produce hormones
- regulates long term processes
nervous system
- relies on
- type of signals
- effects are short or long
- controls
- known as
- neurotransmitters
- electrical signals are fast
- short
- muscles and glands
- “crisis management”
endocrine system
- relies on
- type of signals
- effects are short or long
- controls
- directs
- hormones released into the blood
- hormones travel to tissues and organs
- long
- growth, metabolism, development, and reproduction
- directs gradual, coordinated processes
endocrine system
- group of
- do they contain ducts?
- chemical messengers are
- what do the target cells contain
- type of response
- scattered cells that are not related in function
- no they are ductless so they secrete directly into the blood
- hormones
- protein receptors that bind specific hormones
- physiological
hormones
- ___ diverse
- 3 types
- travel through
- can be __ or ___
- chemically diverse
- AA derivatives
- peptides
- lipid derivatives
- AA derivatives
- free or bound to carrier protein
AA derivatives ex
thyroid hormone and catecholamines
peptide hormone ex
TSH, FSH, LH, ADH, GH, oxytocin and prolactin
lipid derivatives ex
steroid hormones
physiological response of the endocrine system
decrease or increase rate of production of enzymes or proteins; turn enzymes “on” or “off”
mechanisms of hormone action
-2 steps
- activation of membrane receptors
2. activation of intracellular receptors: the gene activation mechanism
activation of membrane receptors
- involves
- signal transduction
- 6 steps
- a receptor on the plasma membrane of target cell
- how hormones alter the activity of target cells
- hormone exits blood and enters intertitial fluid
- it binds to receptor on cell
- this activates a membrane protein = G protein
- a membrane enzyme called adenylate cyclase is activated
- adenylate cyclase catalyzes the conversion of ATP to cyclic AMP
- cAMP leads to alteration of cellular activites
- hormone exits blood and enters intertitial fluid
activation of intracellular receptors: the gene ctivation mechanism
- ex
- 6 steps
- steroid hormones (ex testosterone, estrogen, progesteron)
1. hormone diffuses through plasma membrane
2. it binds to intracellular receptor
3. hormone/receptor complex binds with DNA
4. cause transcription of DNA to produce mRNA
5. translation of mRNA to produce specific proteins
6. New protein leads to alteration of cellular activities
parathyroid gland location
posterior surface of thyroid gland
pineal gland location
roof of 3rd ventricle
endocrine glands
- hypothalamus
- pineal gland
- pituitary gland
- thyroid gland
- thymus
- pancreas
- testes
- ovaries
- adrenal gland
- parathyroid gland
pituitary gland
- aka
- location
- 2 lobes
- lobes connected by
- hypophysis
- within sella turcica
- anterior lobe and posterior lobe
- infundibulum
sella turcica
- part of__
- location
-sphenoid bone which hangs inferior to hypothalamus
anterior lobe of the pituitary gland
- aka
- contains
- function
- adenohypohysis
- a variety of endocrine cells and has an extensive capillary bed
- produces 7 hormones
what does an extensive capillary bed provide
access to blood
posterior lobe of the pituitary gland
- aka
- contains
- neurohypophysis
- contains axons of neurons found in the hypothalamus and an extensive capillary bed
7 anterior pituitary hormones
- thyroid stimulating hormone/thyrotropin
- adrenocorticotropic hormone/corticotropin
- luteinizing hormone
- follicle stimulating hormone
- growth hormone
- prolactin
- melanocyte stimulating hormone
Thyroid stimulating hormone/thyrotropin
- abbr.
- target
- action
- TSH
- thyroid gland
- increase synthesis and secretion of thyroid hormones
adrenocorticotropic hormone/corticotropin
- abbr.
- target
- action
- ACTH
- adrenal gland (outer cortex region)
- increases secretion of cortisol from adrenal cortex
luteinizing hormone
- abbr.
- target
- action
- LH
- gonads
- ovaries: induces ovulation and secretion of estrogen
- testes: stimulates production of androgens
Follicle stimulating hormone
- abbr.
- target
- action
- FSH
- gonads
- ovaries: follicle development and secretion of estrogens
- testes: sperm dev
Growth hormone
- abbr.
- target
- action
- GH
- all tissues particularly skeletal muscles and cartilage
- stimulates cell growth and replication
prolactin
- abbr.
- target
- action
- none
- mammary glands
- stimulates gland development and milk production
Melanocyte stimulating hormone
- abbr.
- target
- action
- MSH
- melanocytes in skin
- stimulates melanocytes (not normally found in adult blood)
posterior pituitary hormones
- antidiuretic hormone
2. oxytocin
antidiuretic hormone
- abbr.
- target
- action
- ADH
- kidneys
- decreases water loss at kidneys
oxytocin
- abbr.
- target
- action
- none
- uterus and mammary glands
- promotes labor and delivery; promotes milk ejection from mammary glands
control of the secretion of pituitary hormones: posterior pituitary
- supreoptic nuclei
- paraventricular nuclei
- hormones travel along
- produce ADH and oxytocin
- produce ADH and oxytocin
- along axons in infundibulum to axon terminals
control of the secretion of pituitary hormones: anterior pituitary
-neurosecretory type of cells in the hypothalamus secrete
releasing or inhibiting hormones into the pituitary plexus
control of the secretion of pituitary hormones: anterior pituitary
- growth hormone releasing hormone
- growth hormone inhibiting hormone
- thyrotropin releasing hormone
- corticotropin releasing hormone
- prolactin releasing hormone
- prolactin inhibitory hormone
- gonadotropin releasing hormone
- release of GH
- inhibits GH
- release of TSH
- release of ACTH
- release of prolactin
- inhibits release of prolactin
- release of LH or FSH
control of the secretion of pituitary hormones: anterior pituitary
- where do hormones go next?
- releasing hormones?
- they enter hypophyseal portal system
- releasing hormone travel to anterior pituitary gland
when releasing hormone travel to anterior pituitary gland what does it stimulate
secretion of target hormones
hypophyseal portal system
capillary network surrounding anterior pituitary gland
neurosecretory system
secrete releasing hormones
negative feedback
controls rate of production of regulatory hormones by the hypothalamus
endocrine glands: the thyroid gland
- location
- shape
- connection
- hormones secreted
- anterior neck, inferior to thyroid cartilage
- butterfly shaped
- isthmus
- thyroxine (T4) and triidothyronine (T3) = thyroid hormones; calcitonin
microscopic structure of the thyroid gland
- type of epithelium
- 3 structures
- cuboidal
- c cells
- follicle cell
- colloid
- c cells
c cells of the thyroid gland
- type of cells
- function
- parafollicular cells
- produce calcitonin
follicle cell of the thyroid gland
-function
produce thyroglobulin which contain thyroid hormones
colloid of the thyroid gland
fluid containing large quantities of thyroglobulin
synthesis and secretion of thyroid hormones
-6 steps
- iodine is transported into follicle cell
- iodine is converted into active form (I+) and linked to tyrosine and incorporated into thyroglobulin
- thyroglobulin with T3 and T4 are secreted into the follicle cavity
- thyroid stimulating hormone stimulates uptake of thyroglobulin/T3 and T4 complex
- T3 and T4 are released from thyroglobulin
6 and &. T3 and T4 are released into the blood
-what regulates synthesis and release of thyroid hormones
TSH
when TSH targets thyroid gland it stimulates
-3 things
- iodine transport into follicle cell
- production of thyroglobulin
- release of thyroid hormones
thyroid hormones are ___ w/o TSH
inactive
function of thyroid hormone
- affects what
- T3/T4 (5)
- affects almost every cell in the body
- increases mitochondrial ATP production
- increases enzyme activity for glycolysis
- increases BMR
- increases heat production
- provides negative feedback to regulate the production of TRH and TSH
- increases mitochondrial ATP production
abnormalities of the thyroid hormone
-2
hypothyroidism and hyperthyroidism
hypothyroidism
-6
- lower than normal T3/T4
- reduced metabolic rate
- reduced appetite with weight gain
- intolerance to cold temps
- weak skeletal muscles
- poor memory and slow reflexes
hyperthyroidism
- higher than normal T3/T4
- increased metabolic rate
- increased appetite and weight loss
- intolerance to heat
- rapid heart rate and increased BP
- increased irritability
3 functions of calcitonin
- regulates concentration of Ca++ of body fluids
- responds directly to concentration of Ca++ in body fluids (DOES NOT involve the hypothalamus or pituitary gland)
- decreases [Ca++] of body fluids
endocrine glands: the parathyroid gland
- location
- 2 types of cells
- hormone secreted
- 2 pairs embedded in posterior thyroid gland
- parathyroid cells and oxyphil cells
- parathyroid hormone
parathyroid hormone
-3 functions
- regulates [Ca++] of body fluids
- responds directly to [Ca++] in body fluids
- increases [Ca++] in body fluids
- low level of [Ca++] in blood
regulation of plasma calcium: high blood calcium
- cell membranes
- release
- effects
- result
- less responsive
- calcitonin
- increase secretion of Ca++ by kidneys
- increases Ca++ deposits in bone by inhibiting osteoclast activity
- increase secretion of Ca++ by kidneys
- blood Ca++ levels are lowered
regulation of plasma calcium: low blood calcium
- cell membranes
- release
- effects
- result
- become too excitable (convulsions and muscular spasms)
- released parathyroid hormone
- release stored Ca++ from bone
- increase reabsorption of Ca++ by kidney
- increase absorption of Ca++ in digestive tract
- release stored Ca++ from bone
- blood Ca++ levels are raised
what does released stored Ca++ form bone do
-increases osteoclast activity and decreases osteoblast activity
endocrine glands: the adrenal gland
- location
- 5 structures
- sites on superior border of each kidney
- capsule
- zona glomerulasa
- zona fasciculata
- zona reticularis
- medulla
- capsule
secretory activities of the adrenal medulla is controlled by the
sympathetic NS
adrenal medulla hormones
- produces
- effects on cellular metabolism
- epinephrine (75-80%) and norepinephrine (20-25%)
- increases metabolism of the cell
adrenal medulla hormones: increasing metabolism of the cell effects
- muscle
- adipose tissue
- liver
- heart
- increases strength and endurance
- increases breakdown of FA
- increases breakdown of glycogen
- increases rate and force of contraction
3 adrenal cortex hormones
- mineralocorticoids
- glucocorticoids
- gonadocorticoids
mineralcorticoids
- mostly
- produced where
- target
- 2 actions
- aldosterone
- in zona glomerulosa
- kidneys
- increases reabsorption of Na+ and H2O
- increases secretions of K+
- increases reabsorption of Na+ and H2O
glucocorticoids
- mainly
- produced where
- target
- action in liver
- action in adipose
- anti inflammatory effects
- cortisol
- zona fasciculata
- most cells
- increase rate of glucose syntheisis and glycogen formation
- increase in FA in blood
- decrease in WBC activity
gonadocorticoids
- cheifly
- produced where
- target
- action: before puberty
- action: adult males
- action: adult females
- testosterone
- zona reticularis
- none
- stimulates pubic hair formation in males and females
- none
- muscle mass, blood cell formation and supports libido
adrenal cortex: regulation of cortisol secretion
- stimuli
- 3 steps (structures)
- stress or low blood glucose levels
- hypothalamus
- anterior pituitary
- adrenal cortex
- hypothalamus
adrenal cortex: regulation of cortisol secretion
-hypothalamus
produces corticotropin releasing hormone (CRH)
adrenal cortex: regulation of cortisol secretion
-anterior pituitary
produces adrenocorticotropin hormone (ACTH)
adrenal cortex: regulation of cortisol secretion
-adrenal cortex
produces cortisol = acts on target tissues to increase fat and protein breakdown
adrenal cortex: regulation of cortisol secretion
-negative feedback
cortisol released has inhibitory effect on CRH and ACTH release
endocrine glands: the pancreas
- location
- endocrine portion of the pancreas %
- 4 cell types
- abdominal cavity
- ~1%
- alpha
- beta
- delta
- F cells
- alpha
endocrine glands: the pancreas
-hormones secreted
- insulin
- glucagon
- growth hormone-inhibiting hormone
- pancreatic polypeptide
endocrine glands: the pancreas
- insulin released by
- glucagon released by
- growth hormone-inhibiting hormone released by
- pancreatic polypeptide
- beta cells
- alpha cells
- delta cells
- F cells
growth hormone-inhibiting hormone
-2 functions
- surpresses release of insulin and glucagon
2. slows rate of food absorption and enzyme secretion along digestive tract
pancreatic polypeptide
-2 functions
- inhibits gall bladder contractions
2. regulates production of some pancreatic enzymes
regulation of insulin and glucagon secretion
- what is pancreas is able to ___ glucose levels
- does it require stimulation from nervous/endocrine system?
- self-monitor
- does not
regulation of insulin secretion
- type of hormone
- secreted in response to
- promotes
- peptide
- secreted in response to an increase in glucose concentration
- promotes the uptake of glucose by body cells
regulation of insulin secretion
-5 effects on target cell include
- increases glucose uptake from blood
- increases glucose utilization and ATP production
- increases glycogen formation in lover and skeletal muscle
- increases triglyceride formation in adipose tissue
- increase AA absorption and protein synthesis
regulation of insulin secretion
-result
excess glucose removed from blood
regulation of glucagon secretion
- stimulated by
- target cells
- goal
- by a decrease in glucose concentration
- liver, skeletal muscle and adipose tissue
- to mobilize energy reserves
regulation of glucagon secretion
- 2 effects
- result
- increases breakdown of glycogen in muscle and liver
- increases breakdown of triglycerides in adipose tissue
- increases breakdown of glycogen in muscle and liver
- release more glucose into blood
diabetes
-definition
general term used to classify a disease with excessive urination
diabetes mellitus
- caused by
- defintion
- inadequate production or insensitivity to insulin
- increased blood glucose levels but cells are unable to take it up = tissues become starved
3 effects of increased blood glucose levels
- overwhelms kidneys (produces large vol of “sweet” urine)
- disturbs neural function and causes muscle weakness
- endocrine system responds as if glucose is in short supply
endocrine system responds as if glucose is in short supply
- effects
- overall effects
- increases glucagon and glucocorticoids
- increases fat metabolism = blood pH decreases
3 complications of diabetes mellitus
- blindess
- cataracts
- kidney failure
complications of diabetes mellitus: blindnesss
neurological problems
complications of diabetes mellitus: cataracts
high risk for heart attack or stroke
complications of diabetes mellitus: kidney failure
vascular problems and erectile dysfunction