chapter 7

Modified sympathetic tissue where preganglionic neuron communicates and medulla release NE and E to go into bloodstream and go throughout the body

adrenal medulla

NE and Epi bind to 2 classes of __________

adrenergic receptors

two types of adrenergic receptors

alpha and beta

can a cell be both inhibitory and excitatory?

You cannot have a cell with both inhibitory and excitatory. Only one each so it will either be inhibitory or excitatory

ACh is degarded by:

acetylcholinesterase (AChE) - enzyme

beta receptors

-generally inhibitory -subclasses beta 1,2,3

indolamines

serotonin

parasympathetic neuron effects

-Preganglionic neuron releases ACh to cholinergic receptors: nicotinic and muscarinic - excitatory -Pace of AP frequency must stay the same when the message is passed along -ACh is the neurotransmitter of parasympathetic - released by both pre and post neurons

effect of cholinergic receptors at target tissue

-decrease heart rate -decrease respiratory rate -increase digestive secretion and motility

alpha receptors

-generally excitatory -subclasses alpha 1 and 2

effects of adrenergic receptors at target tissue

-increase heart rate (B1 receptor) -increase blood (glucose) -decrease digestive secretion and motility (alpha 2 receptor) -increase sweat gland secretion (alpha 1 receptor)

muscarinic receptors:

-on all gland, smooth muscle and cardiac muscle cells that receives cholinergic innervation -receptors are linked to G proteins -ACh binds, G protein cascade causes ion channels to open or close -excitatory or inhibitory due to subclasses of muscarinic receptors

nicotinic receptors:

-on neuromuscular junctions (skeletal muscle), all ANS postganglionic neurons, in the adrenal medulla -receptors are ligand gated channels -ACh binds and channels open; depolarizing the cell -excitatory

As long as neuron is firing APs it is releasing _________, but AChE gets rid of ________ previously when it stops

ACh

how many cranial and spinal nerves are there

Cranial- 12 Spinal- 31

where is acetycholinesterase found? what does it do?

Found at synapse and breaks down ACh so that you cannot continue effect

NE receptors are linked to ___________. function by means of???

G proteins; 2nd messeneger (cyclic AMP)

exception of beta adrenergic receptors being generally inhibitory

NE binding to B receptors of the heart stimulatory

involuntary, cardiac, smooth muscle, glands

autonomic NS

One neuron will leave CNS and stop somewhere along the path to pass signal to second neuron which then takes it to effector

autonomic nervous system

acetylcholine binds to what type of receptor

cholinergic

skeletal muscles are only innervated by ____________

cholinergic receptors

One neuron gives off a bunch of branches and talks to many postsynaptic neuron - called divergent pathway

divergence

catecholamines

dopamine, norepinephrine, epinephrine

most viscera receive nerve fibers from both parasympathetic and sympathetic division

dual innervation

NE and Epi are degraded by:

enzyme monoamine oxidase (MAO)

synthesis of the three catecholamine NTs depends on:

enzyme present in the axon terminals

causes smooth muscles of the digestive tract to contract

excitation

Anytime ACh binds to the channel for nicotinic receptors, it causes ___________________

excitation/depolarization

cluster of cell bodies in PNS

ganglion

produces slower heart rate

inhibition

acetylcholine binds to 2 classes of cholinergic receptors:

nicotinic and muscarinic

Receptors that nicotine in cigarettes bind to

nicotinic receptors

where are adrenergic receptors found?

on glands, smooth muscle and cardiac muscle cells that receive adrenergic innervation

how many neurotransmitters can be released by each neuron

only one

long preganglionic, short postganglionic

parasympathetic

supplies cranial sacral

parasympathetic

• "Rest and digest" • Keeps body energy use as low as possible • Directs digestion and elimination activities

parasympathetic

second neuron ANS

postganglionic neuron

first neuron ANS

preganglionic neuron

One neuron leaves the CNS, and goes all the way to effector (muscle) - somatic motor neuron

somatic nervous system

voluntary, skeletal muscle

somatic nervous system

short preganglionic, long postganglionic

sympathetic

supplies cervical thoracic lumbar

sympathetic

• "Fight or flight" system • Prepares the body to respond to an emergency or threatening situation (or vigorous exercise)

sympathetic

autonomic splits up into:

sympathetic and parasympathetic