Designed by Pyeongsug Kim ©2010 SI session ANS system Spring 2010 Dr. Wright’s Bio 6 Picture from

Designed by Pyeongsug Kim, ©2010 Nervous System CNS PNS Motor neurons ANS SNS Sympathetic Sensory neurons Parasympathetic

Designed by Pyeongsug Kim, ©2010

(Voluntary muscle/Involuntary) muscle Skeletal muscle Excitatory/ Inhibitory Ganglia(Y/N) Motor neurons: &Somatic motorAutonomic motor Somatic motor system Autonomic motor system (Voluntary muscle/Involuntary) muscle ____________________________ & glands Excitatory/ Inhibitory Ganglia(Y/N) Two consecutive motor neurons - Pre- & Postganglionic neuron A single motor neuron to its target cell Neurotransmitter -________________ acetylcholine (Cardiac muscle, smooth muscle) Designed by Pyeongsug Kim, ©2010

Somatic motor vs. Autonomic motor Somatic motorAutonomic motor Voluntary muscle Involuntary muscle & glands (Cardiac muscle, smooth muscle) ExcitatoryExcitatory or Inhibitory No ganglia Ganglia A single motor neuron Two consecutive motor neurons (Pre- & Postganglionic neuron ) The heart, digestive system organs, blood vessels, passages in the respiratory system Skeletal muscle Designed by Pyeongsug Kim, ©2010

___________________________________. ANS helps to regulate the activities of Autonomic Nervous system(ANS) cardiac muscle, smooth muscle, and glands Designed by Pyeongsug Kim, ©2010

A B D F E G Autonomic motor reflex A: B: C: D: E: F: G: Interneuron Dorsal root ganglion Preganglionic neuron Postganglionic neuron Sensory neuron Autonomic ganglion CVentral root ganglion Designed by Pyeongsug Kim, ©2010

Parasymp. Preganglionics release _____. Most postganglionics release _____. Symp. nerves are from _________T1-L2 Parasymp. nerves are from ____________________________ Thoracolumbar division midbrain, medulla, pons,& S2-S4 Craniosacral division Symp. Preganglionics release _____. Postganglionics release _____. ACh norepideline But, A small number release ACh ACh Designed by Pyeongsug Kim, ©2010

Autonomic nervous system SymphatheticParasymphathetic They have (agonistic / antagonistic) effects. The _______________most directly controls activity of ANS. medulla oblongata Designed by Pyeongsug Kim, ©2010

“Fight, flight, and stress” Symphathetic Vs. Parasymphathetic “Rest and digest” Craniosacral division Thoracolumbar division *Preganglionics from T1-L2 *Preganglionics from midbrain, medulla, pons, and S2 - S4 Neurotransmitter Preganglionics –ACh Postganglionics-Norepi. (Some: ACh) Neurotransmitter Preganglionics –ACh Postganglionics-ACh Designed by Pyeongsug Kim, ©2010

↓HR by __________  Opens ____ channels  Normally Symp. and Parasymp. activity influence (SV/HR). ↑HR by ____________.  Opens _____& _____ channels  Symp.(NE, Epi) Parasymp.(ACh) The heart’s rhythm is set by the rate of spontaneous depolarization in the ________. (Autonomic innervation of SA node is main controller of HR.) SA Node Na+ Ca++ K+ Cardiac control center of __________________ this activity of autonomic innervation medulla oblongata depolarization Hyperpolarization Designed by Pyeongsug Kim, ©2010

Our organs are stimulated by… Sympathetic NS vs. Parasympathetic NS Stronger, faster beatsSofter, slower beatsHeart Airway passages Dilate/relax (more airflow) Contract (less airflow) Digestive organs Less activity/relaxMore activity/contract Blood vessels No parasympathetic NS. In blood vessels Contract(less blood flow) - in skin & digestive organs Dilate or relax(more blood flow) - in skeletal muscle, heart, & lungs Designed by Pyeongsug Kim, ©2010

Sympathetic division -Dilates pupil -Inhibit salivation - Puts organs in mode appropriate for threatening or harmful situations. -Puts organs in mode appropriate for relaxed peaceful situations Parasympathetic division Designed by Pyeongsug Kim, ©2010

Sympathetic activity? Parasympathetic activity? Designed by Pyeongsug Kim, ©2010 Sympathetic (Norepi.) parasympathetic(ACh) Sympathetic (Norepi.) parasympathetic(ACh)

Sympathetic activity? Parasympathetic activity? Parasympathetic(ACh) Designed by Pyeongsug Kim, ©2010 Picture from Sympathetic (Norepi.) Parasympathetic(ACh) or can be Sympathetic… “I’m hungry~~~” Me too…

Designed by Pyeongsug Kim, ©2010 Skeletal muscle need lots of energy!  Blood flow toward skeletal muscle (increase /decrease). Blood vessels Contract(less blood flow) - in skin & digestive organs Dilate or relax(more blood flow) - in skeletal muscle, heart, & lungs Remember, the sympathetic actions!  Exercise is (Sympathetic./ Parasym.) activity.

Adrenergic receptors -Receptors for __________________ -Alpha 1 & Alpha 2,  1 &  2, -Causes excitation or inhibition Adrenergic receptors ONLY i  1 - Found ONLY in _____________ cells. (Increase/decrease) heart rates (Contraction/ relex) heart muscle. cardiac muscle  2 - Found in some smooth muscle cells. (Contraction/ relex) smooth muscle.  1 and  2 - Found in some smooth muscle cells. (Contraction/ relex) smooth muscle. Designed by Pyeongsug Kim, ©2010

Cholinergic receptors -Receptors for ____ -Used at all motor neuron synapses on skeletal muscle. -Preganglionics both in Sym. and Parasymp. -Parasymp. Postganglionics -Two kinds of receptors ____________________ Nicotinic & muscarinic Ach Designed by Pyeongsug Kim, ©2010

Nicotinic receptor -Stimulated by ________ -Blocked by _______ -Ligand-gated channels Muscarinic receptor -Stimulated by __________ :Poisonous mushrooms -Blocked by ________ -G-protein-coupled receptors Nicotine curare muscarine atropine Designed by Pyeongsug Kim, ©2010