Autonomic Nervous System III Flashcards
(24 cards)
Homotropic interactions
transmitter inhibits the nerve terminal that it’s being released from
What type of receptor has homotropic interactions
M2 or alpha2
Heterotropic interactiosn
one neurotransmitter affects the release of another via actions of heteroreceptors
What type of receptor has heterotropic interactions
alpha2
Denervation supersentitivity
i. Basically you have like beta blockers that are blocking ganglionic transmission, then you take it away and target organs become supersensitive
Mechanisms of denervation supersentivity
- Proliferation of receptors
2. Loss of mechanisms for removal of transmitter
Cotransmission
neurons release more than 1 transmitter or modulator
Fnctions of autonomic nervous system
help body maintain constant internal environment
accommodate coordinated responses to external stimuli
Are the sympathetic and parasymphatic nervous systems physiologicalopposites?
NO
what neurotransmitters have autoreceptors
NE and AcH
what are sympathetic autoreceptors
alpha-2
what are parasympathetic autoreceptors
M2
activation of autoreceptors causes what
inhibition of release of their subtance
binding of NE to parasympathetic nervce can do whatq
decrease secretion of acetylcholine
acetylcholine released to sympathetic nerve receptors can do waht
decrease release of EN
heteroreceptors on sympaethtic nerves are M2 receptors that do what
respond to ACh to decrease cAMP
heteroreceptors on parasympathetic nerves are A2 receptors that do waht
repond to norepinephrine
neuromodulator
substance/hormone peptide released that affects the release of another neurotransmitter
ATP adn NE when released by small granular vesicles do what
act on receptors to increase Ca++ and cause contraction
what secretes neuropeptide Y (NPY)
large granular vesicles
function of NPY
act on receptors on target organ to cause contraction. At the same time it decreases secretion of other 2 substances
incraeses BP has what affect on baroreceptor discharge
increases
increase in baroreceptor charge does waht
activate vasomotor center to inhibit sympaethtic derive to decrease vasoconstriction
decrease in bp has what affect on the kidney
decreases renal blood flow, increases renin production and angiotensis
