Endocrine Flashcards
(28 cards)
Endocrine Glands
Ductless + secrete hormones into blood neurohormones are secreted into blood
Exocrine Glands
Do not produce hormones –> release sweat and milk
Comparison to NS
- both use chem to communicate
- some chem are used at NT
- both important for survial
- both important for homeostasis
- Ns is wires Endocrine is “wireless”
Major Process controlled and integrated by hormones
- growth and development
- mobilization of body defences against stressors
- maintenance
- regulation of cell metabolism and energy
- blood cell production
- circulation, digestion, absorption
- reproduction
Mechanism of hormone action
- changes in plasma membrane permeability and excitability —> more excitable or depressed
- synthesis of protein
- enzyme activation or deactivation
- induction of secretory release of ANT PIT
- stimulation of mitosis
factors of extent of target cell activation
- blood levels of the hormones
- how fast it is broken down (half life)
- relative amount of receptors for that hormone
- the affinity of the union between the hormone and the receptor (the amount they like each other will aid in target responsiveness)
Upregulation
Increase in # of receptors of another hormone (estrogen increase # of receptors for progesterone and oxytocin during pregnancy uterus is more sensitive )
DownRegulation
hormones causes loss of receptors in another hormone –> prevents from over reaction (# of es
Antagonism
hormones that have opposite reactions
Permissiveness
1 hormone must be present in adequate amounts for full exertion of another hormone
Synergism
action of several hormones are complementary effects is greater than separate effects
Hormone metabolism
hormone conc usually decreases when i is metabolized (except t4 when it tuns in to t3)
Half life
time is take for a hormone to break down by half min - couple of days
ADH
- posterior pituitary
- when blood fluid decreases or osmolality increase (conc of solutes) it signal for more water to be absorbed
- peptide
- neurohormone
Oxytocin
-milk let down, uterine contraction
made in women and men
-peptide
- neurohormone
Prolactin
Ant pit milk production after birth water and electrolyte balance supports male reproductive system PIH (inhibits prolactin because we dont normally need it)-> PRL -Peptide
TSH
Thyroid Stimulating Hormone - Ant pit
Stimulates thyroid gland to produce T3 and T4
TRH (tropic) –> TSH (peptide) –> TH (amine)
-important in young children
ACTH
Stimulates adrenal cortex to release cortisol - ant pit
CRH –> ACTH (peptide) –> Glucorticoids (steroid)
GH
Somatotropin - ant pit - growth and development -amino acids into proteins -protein synthesis in muscles -catabolic breakdown of fats -GHRH --> GH (peptide) --> SOmatomedin (liver most growth from these) or GHIH --> GH (inhibiting growth)
LH and FSH
Gonadotropic - ant pit
FSH - ovary follicle growth and sperm cells
LH - ovulation and testosterone
GnRH –> FSH and LH –> testosterone and Estrogen
steroid
Pineal Gland
Melatonin
- circadian rhythums
- believed that it inhibits LH and FSH –> then ant pit looses sensitivity to it puberty happens
- anitoxidant (gets rid of free radicals that can damage DNA)
- increases with darkness
Adrenal Cortex - Mineral Corticoids
Aldosterone - targets the kidney - retain NA and secrete K - steroid with it you can absorb 8% more salt instead of peeing it out (92 normally + 8)
Adrenal Cortex - Glucocorticoids
Cortisol - steroid
- stimulation of protein degration
- stim glucose from amino acids
- stimulation lipolysis
- you need it to survive
- during stress it provide energy nutrient to body (catabolic) (breakdown of nutrients)
- anti inflammatory
- suppress immune
Thyroid T
T3 (active) and T4 (non active)
needed for metabolic rate
without it Norepi an epi will not be as effective
amine
