Chapter 28 Flashcards
What are the excitatory neurotransmitters?
Glutamate**, 5-Hydroxytryptamine (serotonin), Ach, Dopamine, Aspartate, Histamine, Epinephrine, Norepinephrine
Glutamate HAD A HEN
What are the inhibitory neurotransmitters?
4-aminobutyrate (GABA), glycine, taurine
GTG!
what is the action of an SSRI?
selective serotonin reuptake inhibitors block the reuptake of serotonin. This gives it more time in the synaptic cleft to bind to receptors on postsynaptic neurons
What are the supporting neuronal cells that maintain normal physiology of the nervous system?
glial cells
What are the glial cells of the PNS?
satellite cells, Schwann cells
What is a glial cells of the CNS?
oligodendrocytes, astrocytes, microglia, ependymal cells
What cells make the myelin sheath in the central nervous system? what is the purpose of the myelin sheath
oligodendrocytes. The purpose of the myelin sheath is to insulate the axon and speed up the action potential
what happens in Multiple sclerosis?
an auto immune destruction of oligodendrocytes. When they are destroyed, they are unable to make the myelin sheath which leads to loss of axonal connections and slowed action potentials. This can cause movement/balance disruptions and vision imbalance
what cell regulates molecules necessary for interneuron communication and releases neural growth factors?
astrocytes
what glial cell is closely related to macrophage? what is this cells purpose?
microglia, they work to fight infection by phagocytosis of cell debris when activated
what glial cells produce and regulate cerebral spinal fluid? what special apical structure do they have
ependymal cells, cilia
What kind of signals activate microglia? What type of signaling occurs?
they are activated by pro-inflammatory signals via autocrine signaling. the cell secretes signals which in turn signal itself
What are TNF – alpha, IL –6, NO?
inflammatory signals that activate microglia
 what is the effect of ATP, CX3CL1 on the “macrophage-like” glial cells?
ATP/CX3CL1 are signals that are released from damaged neurons. They activate microglia to produce an immune response to the damage
In what type of cells does the synthesis of acetylcholine occur?
Presynaptic cells
what substrates are needed to synthesize acetylcholine? What enzyme is used?
substrates: choline, acetyl CoA
Enzyme: choline acetyltransferase
What enzyme is used to degrade acetylcholine? what type of reaction occurs
acetylcholinesterase, hydrolysis rxn
How do physostigmine and neostigmine inhibit acetylcholinesterase?
Carbamoylate the serine residue at the active site
what is the effect of acetylcholine on a nerve cell?
it causes the opening of sodium potassium channels in the post synaptic nerve after a stimulus —> depolarization (excitation)
what enzyme is involved in depolarization of the cell by breaking down acetylcholine?
Acetylcholinesterase. It is one of the fastest enzymes since recovery from depolarization occurs in seconds
What organophosphate/nerve gas irreversibly inhibits acetylcholinesterase and how? What is the effect?
DIPF. it TARGETS THE ACTIVE SITE by irreversibly reacting with active site serine and covalently modifying acetylcholinesterase
Effect: respiratory paralysis/death
What compounds inhibit acetylcholinesterase through competitive inhibition with acetylcholine?
tubocurarine, alpha-bungarotoxin, cobra toxin
epilepsy is caused by dysfunction of what neurotransmitter? What is the effect of this dysfunction?
GABA (4-aminobutyrate)
Effect: GABA typically increases the permeability of the postsynaptic membrane to chloride ions, causing hyperpolarization (opposite of excitation). If GABA is dysfunctional, It can lead to prolonged excitation = seizures
What is the treatment for epilepsy? And what is its action?
phenobarbital. It binds to GABA receptors and prolongs the action of GABA. this inhibits action potentials (excitation) and allows for relaxation
What is GABA broken down into (catabolism)?  what are the two enzymes involved?
end product: Succinate
enzymes: GABA transaminase, Succinate semialdehyde dehydrogenase
