Physiology 1: Ans Chp4

Front 1

Tasks of ANS

Back 1

-functions of internal organs
- controls internal milieu of the body:
chemical (pH, O2, CO2), physical parameters (BP, T)

Front 2

Anatomy of ANS

Back 2

-in the periphery the ANS and SNS are almost entirely separated
- in the CNS, the ANS and SNS are intimately connected

Front 3

Sensory input of ANS

Back 3

A. mainly interoceptors (pH, O2, etc.)
B. some: special senses and somatic senses

Front 4

effectors of ANS

Back 4

1. smooth m.
2. cardiac m.
3. glands

Front 5

sensory input of voluntary NS

Back 5

1. special sensory: vision, hearing, taste, smell, equilibrium
2. somatic sensory: pain, touch, pressure, temperature

Front 6

effectors of voluntary NS

Back 6

-skeletal muscles = output, voluntary control

Front 7

Sympathetic gen

Back 7

-fight or flight
- activate resources, stimulate body

Front 8

Parasympathetic gen

Back 8

-regeneration
-restores E
- vegetative aspects of daily life

Front 9

para vs sympathetic NS

Back 9

- many organs are innervated by both, each with a reciprocal effect

Front 10

parasympathetic effects

Back 10

- constricts pupil
-stim salivation
- slows HR
- constricts airways
- stimulates digestion
- contracts ureter
- distendes large intestine: increases tonus, relaxes sphincter
- contracts bladder, relaxes sphincter
- stimulates penile erection

Front 11

sympathetic effects

Back 11

-dilates pupils
- inhibits salivation
- increases HR
- dilates blood vessels
- contracts smooth m.
- liver: stimulates glucose production and release
- pancreas, gall bladder: stimulated release of bile
- stimulates sweat glands
- adrenal medulla: secretion of epi and norepi
- relaxes urinary bladder
-stimulates ejaculation

Front 12

parasympathetic division

Back 12

CNS--> preganglionic neuron (cholinergic)--> ganglion --> postganglionic neuron (cholinergic)---> effector
-each ganglion has over over 100K neuronal bodies

Front 13

muscarinic cholinergic receptors

Back 13

-mimic the effect of ACH
-nicotine has no effect on muscarinic
- toadstool (amanita muscaria)

Front 14

nicotinic cholinergic receptors

Back 14

- mimic the effect of ACH
- muscarine has no effect on nicotinic receptors
- high concentrations of nicotine
block the nicotinic receptors
(parasympatholytic effect)

Front 15

muscarinic

Back 15

-all postganglionic parasympathetic neurons and postganglionic cholinergic sympathetic neurons (smooth m., cardiac m., glands)

Front 16

nicotinic

Back 16

-all preganglionic sympathetic and parasympathetic neurons and motor endplates(synapses) of skeletal m.

Front 17

parasympathomimetic agents

Back 17

-mimic the effects of parasympathetic stimulation
-nicotine and muscarine

Front 18

nicotine

Back 18

-parasympathomimetic
-LD for men: 1mg/ kg
-intoxication: circulatory failure, vomiting, convulsions, respiratory paralysis
- therapy: emetica, gastric lavage, artificial respiration, cardio agents, muscle relaxants

Front 19

muscarine

Back 19

-no pharmacological importance
-intoxication: salivation, sweating diarrhea, vomiting, miosis( constricted pupils), circulatory failure
- antidote: atropine (=parasympatholyticum)

Front 20

parasympatholytic agents

Back 20

-reduce or block the effects of parasympathetic stimulation

Front 21

atropine

Back 21

-parsympatholytic agent
- blocks muscarinic receptors at postanglionic synapses and nicotinic (at high doses only)
-pharmacological effect: tachycardia, relaxation of GI, dilation of bronchioles, madra's, anhydrotic effect on glands
-clinical uses: preanesthetic prevents bradycardia

Front 22

atropine toxicity

Back 22

-considerable interspecies variation
- herbivores generally more resistant: rabbits eat belladonna leaves, horses sensitive
-dry mouth, tachycardia, hyperpnoea, ataxia
-convulsions and respiratory failure can lead to death

Front 23

Curarine

Back 23

-parasympatholytic agent
- prevents the depolarization of postsynaptic membrane of motor endplate (neuromuscular junction)
-muscular paralysis
-curare: hunting pool of S. American natives
- derivatives are peripheral muscle relaxants in IV anesthesia

Front 24

sympathetic division

Back 24

CNS -->cholinergic receptor--> ganglion-->adrenergic receptors--> effectors
-ACH: preganglionic transmitter
- norepi and acetylcholine: postganglionic transmitter
-postgang neurons: sweat glands, piloerector muscles of hair, blood vessels

Front 25

adrenergic receptors

Back 25

-bind both epi and norepi
- classified into alpha (1, 2) and beta (1-3)
- norepi binds better to alpha receptors (stronger effect)
-epi bind better to beta receptors

Front 26

norepi

Back 26

-synthesized from the amino acid tyrosine
-stored in vesicles
-degraded by mitochondrial monoamine oxidase (MAO) and intracellular (smooth, heart gland) catechol-O-methyltransferase (COMT)

Front 27

effect of norepi on organs

Back 27

-alpha receptors
- vessels: constriction (1,2)
- bronchi: constriction (1)
- fat cells: dec. lipolysis (1,2)
- insulin secretion: inhibits (2)
- liver: glycogenolysis inc.
- renin release: stimulation
-GI tract motility: relaxation (2)

Front 28

effect of epi on organs

Back 28

-beta receptors
- heart: +chronotropic, dromotropic, inotropic, and bathmorphic
-vessels: constriction (2>1)
- bronchi: constriction (2>1)
- fat cells: lipolysis inc. (2>1)
-insulin secretion: stim (2>1)
- liver: glycogenolysis inc
-renin release: stimulation
-GI tract motility: relaxation (2>1)

Front 29

sympathiomimetic agents

Back 29

mimic the effects of sympathetic stimulation

Front 30

epi

Back 30

-sympathiomimetic agent
-adjunvans to local anesthetics
-causes constriction of blood vessels which extends the duration of the anesthesia

Front 31

amphetamine

Back 31

-sympathiomimetic agent
- stim of CNS: alertness, dec. fatigue
- marked peripheral alpha and beta effects (similar to norepi)
- effects diminish after repeated application (=tachyphylaxis) despite increase of dose
- abuse as a performance enhancer and associated risk of habit formation

Front 32

alpha blockers

Back 32

-sympatholytic agents
- clinical use in the treatment of peripheral vasospasm

Front 33

beta blockers

Back 33

-sympatholytic agents
- grouped as:
1. selective: mainly 1, 2 or 3
2. non-selective: 1, 2, and 3
-eg beta 1 blockers such as atenolol in heart: prophylaxis of agina pectoris, arrhythmias