endocrine pwp 1 phys Flashcards
protein based hormone location of receptor
cell membrane surface
is a protein based hormone bound to a carrier protein?
what is the result of this?
no
because of this they have shorter half lifes
how long are the effects of a protein based hormone compared to a steroid hormone?
the steroid lasts longer than a protein based
the effect that protein hormone has on a cells target is
increase of cell metabolism
the effect that a steroid hormone has on target cell is
increased protein synthesis
the mechanism of action of a protein hormone?
- G protein associated with receptor
- production of second messenger
- increased/decreased enzymatic activity in cell
the mechanism of action of a steroid hormone
Activation of specific genes
DNA-mRNA
steroid hormones increase what?
protein synthesis
do protein carries have a longer half life? AND why?
yes because of being bounded to a carrier protein
location of receptor of a steroid based hormone
intracellular/intranuclear
when a persons hormone increases their receptors this is known as
up regulation
What is the process called when prolactin increases its receptors in the breast?
up regulation of receptors
an adult with NIDDM will have a decrease in receptors for insulin on adipose tissue:
this process is known as
down regulation
sensitivity of a target tissue can e changed in one of two ways
changing the number of receptors
changing the number of receptors
dose response relationship is a direct relationship meaning that as the dose increases what happens to the response?
in will increase
dose is referring to the
concentration of the hormone
what must a target cell posses in order for it to react?
a specific receptor for it
these proteins are essential for mediating the hormonal response
steroid hormones
a second messenger is used in protein hormones as a
mediator of the hormonal response
in a protein hormone response what is altered within the cell?
activity or concentration of enzymes, carrier proteins
what is the role of a G-protein?
it links the hormone receptor to the second messenger mechanism
the process of protein hormone producing a second messenger
hormone –> receptor –> G protein —> enzyme –> 2nd messenger
what Enzyme is responsible for stimulating cAMP?
adenylyl cyclase
cAMP is a common
2nd messenger
what does cAMP activate?
protein kinase A
Protein kinase A leads to teh
phosphorylation that either activates or inactivates target enzymes
endocrine system is the primary system that
maintains homeostasis
paracrine
cells secrete products to extracellular fluid of neighboring cells
autocrine
cell secretion products affect the function of the same cell be binding to cell surface receptors (self regulation)
cytokine
secreted cell proteins can function as autocrine or paracrines, or endocrines and often act on a broad spectrum of target cells (immune response)
neuroendocrine
secretions products from neurons –> circulating blood and influence the function of target cells some distance away
endocrine
hormones released from specialized glands or cells reach bllod and influence glands at a distance away
neural
NT are released at the synaptic junction and act locally (RAPID)
endocrine rate of response vs nervous system?
endocrine is prolonged while neuro is rapid
hormones are released directly into
the tissue fluids and NOT through ducts
systemic effect hormones
growth hormone
thyroid hormone
insulin
Local effect hormones
TSH
Adrenocorticotropic (ACTH)
if a hormone stimulates a specific hormone is it known as a
local effect
can cells have MANY receptors to MANY other hormones?
yes
target cells are equipped with protein receptors with what characteristics?
high affinity and specificity
amines are a derivative of
tyrosine
inactive hormone is called a
prohormone
