Chp 17-18 Flashcards
what are autocrine chemical messengers
released by cell- a local effect on same cell.
what are paracrine chemical messengers
act locally on nearby cells- released by one cell type into extracellular fluid - surrounds other cell types.
what are neurotransmitters
secreted by neurons- secreted by presynaptic nerve terminals. influences postsynaptic cells like other neurons, muscle cells, or glandular cells
what are endocrine chemical messengers
released by certian cells and endocrine glands –> bloodstream.
what are the classes of chemical messengers
autocrine
paracrine
neurotransmitters
endocrine
autocrine
secreted by cells in a local area. influences the activity of the same cell from which it was secreted.
paracrine
produced by a wide variety of tissues and secreted into extracellular fluid. has a localized effect on other tissues
neurotransmitter
produced by neurons. secreted into a synaptic cleft by presynaptic nerve terminals. travels short distance. influences postsynaptic cells
endocrine
secreted into the blood by specialized cells. travels some distance to target tissues. results in coordinated regulation of cell function
what is purpose of glands
secrete chemical signals into circulation
what does hormone act on
target tissues
what are characteristics of endocrine system
glands
hormone
regulate activities of body
ligands
what are some hormone characteristics
released in small quantities
transported some distance in the blood
they act on target tissues
what are some similarities between nervous and endocrine systems
both systems associated with hypothalamus
the same molecule may be used as a neurotransmitter by the NS or a hormone in the ES
two systems cooperate
nervous system secretes neurohormones into circulatory system
some parts of endocrine system innervated directly by nervous system
what is a neurohormone
oxytocin
what are some differences between the nervous and endocrine systems
mode of transport
speed of response
duration of response
what is the speed of response in the nervous
miliseconds
what is speed of response in endocrine
delayed seconds
what is duration of response in nervousq
milliseconds
what is duration of response in endocrine
minutes
what is amplitude vs frequency
strength of concentration vs frequency of AP
what are general characteristic of hormones
stability
communication
distribution
what is a halflife
time for half of the dose to be eliminated
what is a long half life
few days to a few weeks. usually lipid soluble
released at constant rate through time
what is short half life
water soluble hormones. rapid onset and short duration
what is communication in hormones
interaction with target cell to get a specific response.
what is distribution in hormones
hormones dissovle in blood plasma
distributed quickly
what are some water soluble hormones
protiens
peptides
amino acid derivatives
what are some patterns of hormone secretion
chronic
acute
episodic
what is chronic hormone secretion
maintence of relativiely constant concentration of hormone.
what is acute hormone secretion
epinephrine in stress
what is episodic hormone secretion
hormone regulation. female reproductive hormones
what are most hormones controlled by
negative feedback
what are 3 types of stimuli that regulate hormone release
humoral
neural
hormonal
what are some examples of autocrine
eicosanoids
prostaglandins
thromboxanes
what are some examples of paracrine
somatostatin, histamine, eicosanoids
What are some examples of neurotranmitters
acetylcholine, epinephrine
what are some examples of endocrine
thyroid hormines, growth hormone, insulin, epinephrine, estrogen, progesterone, testosterone, prostaglandins.
what are some examples of lipid soluble hormones
steroids
amino acid derivative
fatty acid derivatives
What is the structure of steriods
testosterone, aldosterone
what is the structure of amino acid derivative
tyroid hormone
what is structure of fatty acid derivaties
prostaglandins
what are some examples of protiens
tyroid stimulating hormone, growth hormone
what are examples of peptides
insulin, thyrotropin releasing hormone
what is example of amino acid derivative
epinephrine
what is humoral stimuli
blood borne molecules that stimulates release of a hormone in response to the molecules concentration level in the blood.
what is neural stimuli
AP, neurons release a neurotranmitter into the synapse with the cells that produce the hormone.
what is hormonal stimuli
one endocrine gland hormone stimulates the secretion of another endocrine gland.
what is a neural stimuli in response to
exercise
what is the part of molecule where hormone binds
binding site or receptor site.
what can thyroid hormones not bind to
insulin receptors
what does changing the number of receptors ensure
an optimal target tissue response.
what are the two ways down regulation occurs
when the rate at which receptors are synthsized decreases in some cells after the cells are exposed to a hormone.
the combination of hormones and receptors can increase the rate at which receptor molecules are degraded.
how does the receptor number increase
increase in synthesis of receptors. thus increased sensitivty to the hormone
what is an example of up regulation
FSH stmulates an increase in receptor synthesis of LH receptors in ovary cells. Which ncreases ovary cell sensitivity to LH.
which is not a class of hormone receptor
plasma binding protein
what are two types of hormone receptors
membrane bound receptors
nuclear receptors
what do lipid soluble hormones bind to
nuclear receptors
what happens with nuclear receptors
lipid soluble pass through plasma membrane
react either with enzymes in the cytoplasm or with DNA regulates transciptions of genes in the target tissue.
what are examples of nuclear receptors
thyroid hormones, steroid hormones, testosterone, estrogen,
membrane receptors
integral proteins with receptor site at cell surface- hormones cant pass through membrane.
what happens with membrane bound receptors
water soluble,
large molecular weight
a few smaller molecules
what are hormone examples of lipid soluble
steroid hormones testosterone estrogen progesterone aldosterone cortisol thyroid hormone vitamin D
what are some hormone examples of water soluble
luteinizing hormone follicle stimulating hormone thyroid stimulating hormone adrenocorticotropic hormone glucagon oxytocin calcitonin parathyroid hormone epinephrine insulin growth hormone prolactin
where are receptor proteins found
in cytoplasm or nucleus
receptor hormone complex binds to hormone response element on the DNA transcription of mRNA in the nucleus takes place followed by translation in the cytoplasm at the ribosome.
..
what is the latent period
need time to produce mRNA protein.
how long does it take for target cells to produce a new protein
several hours.
what are hormones that bind to membrane bound receptors
proteins, peptides, and some amino acid derivaties like epinephrine, and noropinephrine.
what are two results when hormone binds to receptor protein
alter the activity of g proteins- that causes the production of the intracellular mediator
alter the activity of th intracellular enzymes.
which is not a class of hormone receptor
plasma binding protein
what can activated alpha subunits of the g protein alter
the activity of enzymes inside the cell
what happens when glucagon binds to glucagon receptors
alpha subunit of the g protein binds to adenylate cyclase and activiates it.
what does the increase in cAMP activate
protein kinase enzymes
what does DAG regulate
protein kinases and those that synthesize protaglandins contraction of smooth muscle.
what does IP3 cause increase of
Ca2+ in cytoplasm contraction of smooth muscle
what does cGMP activate
enzymes that increase Na+ and water excretion by kidney
what are some endocrine system functions
metabolism and tissue maturation ion regulation water balance immune system regulation heart rate and blood pressure regulation control of blood glucose and other nutriets control of reproduction uterine contractions and milk release
what is the pituitary gland and hypothalamus
junction of nervous and endocrine systems
how many hormones does pituitary secrete
nine
what are two functions of pituitary
regulate body function
regulate secretions of other endocrine glands
what does hypothalamus regulate
secretions of anterior pituitary
what is function of anterior pituitary
secrete hormones
what is another name for the anterior pituitary
adenohypophysis
what is another name for posterior pituitary
neurohypophysis
what is TRH
thyroid releasing hormone
what is TSH
thyroid stimulating hormone
What is CRH
corticotropin releasing hormone
What is GnRH
gonadotropin releasing ormone. KH and FSH
what is PRH
prolactin releasing hormone
what are some releasing hormones
TRH
CRH
GnRH
PRH
what does antidiuretic hormone do
prevents outputs of large amount of urine
promotes retention of water in kidney tubules with reduces urine volume
constricts blood vessels and raises blood pressure.
what is osmoreeceptors
specialized neurons of hypothalamus that measures changes in concetrations of electrolytes and H2O
what are baroreceptors
specialized neurons in the walls of the atria of the heart, carotid arteries, and the aortic arch. sense changes in blood pressure.
what is the target tissue for ADH
kidney
when ADH levels increase ho is urine volume affected
less urine is made
when ADH levels increase how is blood volume affected
blood volume increases as more water is kept by the kidney
what is diabetes insipidus
not enough ADH produces
usually from brian damage
what does growth hormone do
increase uptake of amino acid protein synthesis
increase fat breakdown and stimulates synthesis of glucose by the liver which releases glucose in the blood.
increases tissue growth
what does growth hormone regulate
growth, tissue maintenence, metabolism
what happens as GH binds to adipose cells
incresses breakdown of lipids and decreases use of glucose as energy
what is indirect effect of GH
increaes the production of somatomedins in the liver and skeleta; muscle.
what are peak levels of Gh
during deep sleep
what is dwarfism
chronic hyposecretion of GH
what is hypersecretion of GH
giantism- before epiphysial growth plate closes
acromegaly0 after closure
what is prolactin
milk production
where does TRH come from
hypothalamus and throid hormone from the tyroid.
Where is TSH from
anteriror pituitary thyroid gland synthesis.
where is cortisol secreted from
adrenal cortex.
where is aldosterone secreted from
adrenal cortex.
what do lipotrophins do
bind to adipose cells to catabolize fat and release fatty acids into the cir system.
what is addisons disease
chronic adrenal insufficiency adrenal cortex degenerates loss of negative feedback on pituitary excess ACTH secretion weight loss, weakness, low blood pressure, arkening of skin.
what molecule has the same effects as opiate drugs
endophin.
what do LH and FSH promote
growth and function of the gonads. testes and ovaries.
what is the thyroid gland
large endocrine gland. high vascular. iodine enters follicular cells by active transport
what are follicles
small spheres with follicular cells surronding thyroglobin protein and large amounts of thyroid hormones.
what are parafollicular cells
secrete calcitonon which helps regulate calcium concentration.
what do follicular cells do
secrete thyroglobulin inside follicle. iodine attaches to tyrosine. the two tyrosines combine into curculation.
what is congenital hypothyroidism
defeciencu of iodine or congenital erros in tyroid hormone synthesis
impairment of physical and mental growth
cretin not used much now.
what is a hoiter
abnormal enlargemtn of the tyroid gland
the major more potent form of tyroid hormone that interacts with target cells is
triiodothyronine.
what condiditon produces elevated TSH secretion
iodine deficeincy
surgically removed thyroid
pituitary tumor
what is calcitonin secretion triggered by
high Ca+2 concetration in blood.
what is parathyroid gland
embredde din thyroid
tow glands on each side
secrete PTH
target tissues, bones, kidneys, intestines.
increase calcium in blood
stimulates osteoclasts
promotes calcium reabsorption by kidneys and PO4 excretion.
what is causes of hypoparathyroidism
accidental removal during thyroidectomy.
what are symptoms of hypoparathyroidism
hypocalcemia normal bone structure increased neuromuscular excitability raccid heart musslce, cardiac arrhythmia may develop diarrhea
what is adrenal gland composed of
inner medulla and outer cortex
what id medullar formed from
neural crest cells
what is cortex derived from
mesoderm
what does epinephrine do
increase glucose in blood
oncrease fat breakdown
dilates skeletal and cardiac muscle blood vessels
what does norepinephrine do
increae heart rate, force of contraction and BP. vasoconstriction.
what are symptoms of pheochromocytoma
elevated BP elevates heart rate pallor nervous increases chance of heart disease
what are the five actions of epiephrine
release glucose from liver release FA from adipose increases heart rate decreases blood flow increased blood flow to muscles.
what does aldosterone do
increase rate of sodium reabsorption by kidneys. increases sodium levels in blood
what does cortisol do
increases fat and protein breakdown and glucose synthesis. decreases inflammatory response.
what are the metabolic effect of glucocorticoids
increases fat and protein breakdown for energy
increase glucose synthesis
what are the anti inflammatory effect of glucocorticoids
antibody production, release of inflammatory chemicals, and WBC>
what are alpha cells
glucagon
what are beta cells
insulin
what are delta cells
somatostatin
what does insulin target
liver, adipose, muscle, satuety center.
what does insulin do
increase uptake of glucose and amino acids by cells.
what does glucagon target
liver
what does glucagon cause
breakdown of glycogen and fats for energy
what happens wht glucose levels are high
rapid uptake and storage of glucose, AA and fats.
what happens when glucose levels are loq
glucose is released and a switch to fat and protein are sources of energy
what does testosterone fdo
regulates production of sperm cells
development maintan male reproductive organs
secondary sex characteristics
what does estrogen do
uterine and mammary gland development and function
external genitalia structure
secondary sex characteristics
what does pineal gland produce
melatonin
what is thymosin
development of the immune system
what are paracrines
chemical mediators of inflammation released from injured cells.
what are the efect of aging on the endocrine system
gradual decrease in secretory activity of some glands .
lower GH
melatonin
thyroid hormone
kidneys secrete less renin
tendency to develp type 2 diabetes and grow older.
