Nervous System 4 Flashcards
________ Controls the visceral functions of the body by monitoring (sensory) and adjusting (motor) the activity of cardiac muscle, smooth muscle, glands and adipose tissue.
Autonomic Nervous System
A ____ of the brain refers to gray matter in the CNS that have specific job
Center
In the ____ nervous system, Both systems are Involuntary, Excitatory & Inhibitory, Di-synapticGenerally oppose one another when they innervate the same tissue.Each system is tonically active, but one system is usually predominant at rest.
Autonomic NS
Fight or Flight•Can selectively activate effectors or elicit a mass discharge, especially during stress response•Noraderenergic (NE)/Adrenergic (EPI)–BUT cholinergic pre- to post-ganglionic
Sympathetic (SNS)
Rest & Digest•Control mechanisms are almost always specific, activating or inhibiting discrete targets.•Cholinergic (ACH)
Parasympathetic (PNS)
_____ neurons are (cell bodies in lateral gray horn of the spinal cord (SNS) or motor nuclei of cranial nerves III, VII, IX and X (PNS))
Preganglionic neurons
In ANS, All preganglionic terminals release ___ that binds to _____ receptors on the postganglionic neuron
Ach; nicotinic receptors (Type NN)
_____ receptors are ligand-gated ion channels (ionotropic) that are selective for both Na+ and K+.
nACh receptors
Thoracolumbar Division (T1 through L3 or L4)B. Preganglionic axons exit through a white ramus into one of the ganglia of the sympathetic chain. Fibers will then either 1.Synapse with postganglionic neurons at that ganglia 2.Pass up or down the sympathetic chain, then synapse with a different ganglia 3.Pass through the chain and out a sympathetic nerve (Splanchnic) where it will synapse in a peripheral sympathetic ganglion (celiac, superior mesenteric, or inferior mesenteric) 4.EXCEPTION: Adrenal Medulla
Sympathetic Nervous System
Almost all sympathetic postganglionic terminals release ____ at synapse with target cells.
norepinephrine (NE/noradrenaline)
Exception: most sympathetic post-ganglionic terminals release ____ at sweat glands to activate muscarinic receptors. Some skeletal muscle vasculature also works this way.
ACh
NE activates both ___ and ____ receptors
Alpha and Beta
When stimulated, the adrenal medulla (chromaffin cells) secretes 80% _______ and 20%_____ into the bloodstream.
80% epinephrine (EPI/adrenaline) and 20% NE
____ (Epi or NE) has a slightly greater potency at alpha receptors
NE
_____ receptors: constrict smooth muscle (Gq protein, Increased IP3); increased Ca; vasoconstriction
Alpha 1:
_____ receptors: blocks further NE release (presynaptic receptor) (Giprotein, decreasedcAMP)
Alpha 2
____ has MUCH greater potency at Beta 2 receptors
Epi
____ has slightly greater potency at Beta 3 receptors
NE
____ receptor: increase heart rate & contractility, increase lipolysis, increase renin secretion, increase protein content in saliva (Gs protein:increased cAMP); seen in the heart
Beta 1:
____ receptor: relax smooth muscle, release FA & glucose (Gs protein: increased cAMP); vasodilation
Beta 2
___ receptor: found in adipose tissue (Gs protein: increased cAMP); breaks down fat
Beta 3
Addition of EPI to lidocaine usually extends the duration of anesthesia by at least 50% due to its interaction with ____ receptors that causes vasoconstriction
Alpha 1
Albuterol, which is a _____ (receptor) selective agonist, is used for treatment of asthma as it causes bronchodilation.
Beta 2
____ that is released by nerve terminals remains active for only a few seconds before:1.Diffusion away from synaptic cleft 2.Reuptake by presynaptic terminal (cocaine blocks re-uptake) 3.Destruction by the enzymes MonoAmine Oxidase (MAO) or Catechol-O-Methyl Transferase (COMT)
NE
____ Inhibitors (ex. Selegiline) are a class of drugs used to treat some medical conditions (Parkinson’s Disease, Depression, Social Anxiety, etc.). Side effects of MAOIs include xerostomia, nausea, etc.
MAO
____ has longer preganglionic axons
PNS
What CNs give parasympathetic innervation?
3, 7,9,10
Postganglionic parasympathetic varicosities release ACh that bind to _____ ACh receptors on target cells.
muscarinic
Digestion Urination, Miosis, Bronchoconstriction, Bradycardia, Lacrimation are actions of _____ via ____ receptors
Actions of the PNS via Muscarinic Receptors
____ receptors Constrict smooth muscle–Relax sphincters –Stimulate glandular secretions
Muscarinic receptors (G-protein/metabotropic)
____ receptor: stomach (secretions and contraction), salivary glands (Gq: IP3, increased IC Ca++)
M1:
____ receptor: smooth muscle, myocardium, cardiac autorhythmic cells, CNS(Gi protein, decreased cAMP)
M2:
____ receptor: exocrine glands (ex. salivary), smooth muscle, endothelium, CNS (Gq: IP3, increased IC Ca++)
M3:
____ receptor: CNS, vagal nerve (Gi protein, cAMP)
M4:
_____ receptor: sweat glands (SYMPATHETIC FUNCTION) (Gq: IP3, Increased IC Ca++)
M5:
____ can occur in patients taking anti-cholinesterases
Sialorrhea (drooling)
____ drugs block PNS target cell activity; could have effects like xerostomia, constipation, ileus, and nausea and vomiting
Anticholinergic drugs
In the bladder, which receptor in PNS relaxes sphincter?
M2
In the bladder, which receptor in PNS constricts detrusor?
M3
In the bladder, which receptor in SNS constricts sphincter?
Alpha 1
In the bladder, which receptor in SNS relaxes detrusor?
Beta 2
In the GI tract, which receptor in SNS relaxes muscle?
Beta 2
In the GI tract, which receptor in SNS constricts sphincter?
Alpha 1
In the GI tract, which receptor in PNS relaxes sphincter?
M2
In the GI tract, which receptor in PNS constricts muscle?
M3
In the salivary glands, which 2 receptors of PNS stimulate lots of watery secretion due to contraction of myoepithelial cells and vasodilation
M1 and M3
Which receptor of SNS causes vasoconstriction of blood vessels?
Alpha 1
Which receptor of SNS causes vasodilation of blood vessels?
Beta 2
IN salivary glands, which SNS receptors cause vasoconstriction and secretion of concentrated saliva?
Alpha 1
IN salivary glands, which SNS receptors stimulate secretion of protein?
Beta 1
The diameter of most arterioles in the body are not regulated by which branch of the ANS?
PNS
Meth mouth is due to ___ receptors causing excess vasoconstriction and reduced salivary flow
Alpha 1
Which PNS receptor in the heart keeps predominant tone; keeps HR low/
M2
Which SNS receptor in the heart increases heart rate and contractility
Beta 1
Which SNS receptor in the heart increases coronary blood flow via dilation?
Beta 2
Which SNS receptor in the lungs relaxes bronchial smooth muscle?
Beta 2
Which PNS receptor in the lungs keeps predominant tone and constricts bronchial smooth muscle?
M3
