Chap:5 How do neurons used electrochemical signals to communicate and adapt?

dendrodendritic

dendrites send messages to other dendrites

neurotransmission

1. synthesis 2.release 3.receptor action 4.inactivation

what determines what is a neurotransmitter

1.chemical must be synthesize or present in neuron 2.when released, it must produce response in target cell 3.same receptor action must be obtained when chemical is experimentally placed on target 4.there must be a mechanism for removal after chemical work' is done

Cholinergic system

Acetylcholine -> plays a tole in normal working behavior, attention and memory

what are the 4 types of small molecules neurotransmitters

Acetylcoline synthesis Amine synthesis Serotonin synthesis Amino Acid synthesis

Acetylcoline made up of

Choline and Acetate

The 4 types of activating systems in CNS

Cholinergic system dopaminergic system noradrenergic system serotenergiic system

Amino Acid synthesis makes

GABA GLUTAMATE

2 types of receptors in postsynaptic neurons

Ionotropic receptor metabotropic receptor

3 types of neurotransmitters

Small molecules peptide (neuropeptides) tranmitter gasses

Transmitter Gasses

Synthesized in the cell as needed. Very fast acting, activate metabolic processes in cells such as MODULATING PRODUCTION OF OTHER NTs. Ex: nitric oxide, carbon monoxide.

Activating systems

Uses specific neurotransmitter to control other places. neural pathway that coordinates brain activity through a single neurotransmitter; cell bodies are located in nucleus in the brainstem and axons are distributed through a wide region of the brain

neurotransmitters

a chemical released by a neuron onto a target with an excitatory0 or inhibitory effect. Acts in the CNS, out side the CNS is called a hormone

Learning

a relative change in behavior that results from experience

Acetylcholine (ACh)

activities skeletal muscles ans can inhibit or slow down heart beat. First neurotransmitter discovered in the peripheral and central nervous system; activates skeletal muscles in the somatic nervous system ans may either excite or inhibit internal organs in the autonomic system

Dopamine

amine neurotransmitter that plays a role in coordinating movement, in attention and learning, ans in behavior reinforcing

Glutamate

amino acid neurotransmitter that excites neurons. Pumps you UP - Sympathetic System

GABA

amino acid neurotransmitter that inhibits neurons. COMES you Down. -Parasympathetic

Synapses were first seen through

an electron microscopes

Sensitization

an enhanced response to a stimulus where synapses change at the potassium channel. More POTASIUM leads to greater Neurotransmitter in the synapse creating larger response to same stimulus

Axoaxonic

axon terminal ends on another axon

axosynaptic

axon terminal ends on another terminal

axosomatic

axon terminal ends on cell body

axosecretory

axon terminal ends on tine blood vessel and secretes transmitter into blood stream

axodendritic

axon terminal of one neuron synapses on dendritic spine of another

Ionotropic receptor

binding site for NT ans has a channel for Na+, K+ to cross the membrane (the shape of the protein changes as the ions travel through). RAPIDLY changes voltage across membrane . Usually EXITATORY- Triggers action potentials

Metabotropic receptor

binding site for NT but no channel of its own. It Activates other channels near it to open or close for ions to cross membrane. Linked to a G protein that can affect other receptors or act with second messengers to affect other cellular processes. Alpha sub unit attaches to the near by channel to open it or Alpha sub unit attaches to enzyme and then the enzyme creates a secondary messenger that causes a channel to open.

Epinephrine (adrenaline)

chemical messenger that acts as a hormone to mobilize the body for fight of flight during times of stress ans as a neurotransmitter in the central nervous system.

Synaptic variety

dendrodendritic axodendritic axoextracellular axosomatic axoaxonic axosynaptic axosecretory

how are neurotransmitters deactivates?

diffusion degradation re-uptake glia uptake

dopaminergic system

dopamine: coordinating movements and involved in addictive behavior

degradation

enzymes break down neurotransmitters in the synaptic cleft to create building blocks to create new ones

Amine synthesis includes

epinephrine dopamine nor-epinephrine

gap junction

fused prejucntion ans postjucntion cell membrane in which connected ion channels form a pore that allows ions to pass directly from one neuron to the next

re-uptake

membrane transporter proteins can break down or take whole neurotransmitters back into presynaptic neuron

Seretonin synthesis controls

mood/ agression / sleepiness / daily activities to live

Small molecules neurotransmitters

most common in nervous system. quick acting NT synthesized in the axon terminal from products derived from the diet.

Peptides (neuropeptides) Neurotransmitters

multifunctional chain of amino acids that act as Neurotransmitters. TAKE MORE TIME TO Synthesis than small molecules. Ex: opioid, insulin, corticosteroid

Norepinephrine (noradrenaline)

neurotransmitter found in the brain and in the sympathetic division of the autonomic nervous system; accelerates hear rate in mammals

1.Synthesis

neurotransmitters must be made to be ready to be released when action potential travels down the axon

4.inactivation

neurotransmitters then either keep working in the synapse or is broken down into molecules and taken into the synaptic neuron

noradrenergic system

norapinephrine: may stimulate neurons to change structure during learning , emorional processing

Amine synthesis depends on

rate limiting factors, which are any enzyme that is in limited supply, thus restricting the pace at which a chemical can be synthesized

serotenergic system

seratonin: weakfulness, mood, plays a role in learning

glia uptake

some glia take in the neurotransmitter and can store it for future use in the synaptic cleft through phagocytosis

diffusion to deactivate neurotransmitters

some neurotrnamitters diffuse away from receptors sites to no longer act on the receptor

neurotransmitters must cross the

synaptic gap once released by a vesicle in the presynaptic neuron

axonextracellular

terminal with no specific target. secretes transmiter to extracellular fluid

Habituation

the response to a stimulus WEAKENS with repeated presentations of the stimulus. can happen with all the senses. NEURAL BASIS: as habituation develops, the EPSPs in motor neurons become smaller, calcium channels, less neurotransmitters are transmitted from presynaptic neuron.

3.Receptor action

transmitter activated receptors receive neurotransmitters on postsynaptic membrane and new action potential is generated

Seretonin depends on

triptophan

2.Release

upon action potential reaching the axon terminal, Neurotransmitters must be released to the synaptic cleft (gap)

In the synapse glia cells

work to provide the building blocs for the synthesis of neurotransmitters and help "mop up" used neurotransmitters