Lec 12 Flashcards
Homeostasis maintained via ——
ANS,endocrine, behavioral system
Responses
Autonomic
Endocrine
Behavioral
Some autonomic functions can occur without brain output
Baby urinate
Homeostasis is dynamic balance
Parasympathetic rest
Sympathetic fight/flight
Antagonist control
One Autonomic branch is excitatory
Other is inhibitory
Antagonistic control for heart
Parasympathetic: slow rate
Sympathetic: increase rate and force of contraction
Antagonistic gI tract
Parasympathetic: promotes digestion
Sympathetic: slow/halt digestion
Most are antagonistic but
There are some exceptions
Ex. Blood vessels
Only SNS input and under tonic control
—— regulated by increase/decrease of SNS activity
Sympathetic origin in cns
Thoracolumbar
Sympathetic ganglion location
Sympathetic ganglia/chain
Parasympathetic origin of CNS
Brainstem
Sacral segment
Parasympathetic ganglion location
Close to target
Parasympathetic pathway
Long preganglionic neurons
Short post preganglionic neuron
Sympathetic pathway
Preganglionic neuron short
Postganglionic neuron long
Autonomic pathways consist of two neurons
Preganglionic neuron neurotransmitter is always acetylcholine
Difference between sympathetic and parasympathetic
-CNS origin of preganglionic neurotransmitters
-location of peripheral autonomic ganglia
-relative lengths of pre- and postganglionic neurons
-receptors at target synapses
Sympathetic pathways
Use acetylcholine and norepinephrine As neurotransmitters
Preganglionic is short
Adrenergic receptor — GPCR
Parasympathetic pathway
-Use only acetylcholine as neurotransmitter
-Muscarinic receptor —— GPCR
Autonomic synapses at target are
Neuroeffector junction
Varicosities
Swollen regions of axons filled with neurotransmitter vesicles
