Test 1

Question 1

What are the key neurotransmitter systems targeted by psychotropic drugs?

Answer 1

Serotonin, Norepinephrine, Dopamine, Acetylcholine, Glutamate, GABA (y-aminobutyric acid)

Question 2

Do behavioral symptoms occur when neurons malfunction?

Answer 2

Behavioral conditions do occur when neurons work abnormally

Question 3

What is the name of the marijuana the brain makes?

Answer 3

Anandamide (endogenous marijuana)

Question 4

The cells of chemical communication in the brain are called?

Answer 4

Neurons

Question 5

What are the three types of neurotransmission?

Answer 5

Classic, Retrograde, and Volume

Question 6

What is a gap or space between two neurons where communication or neurotransmission takes place called?

Answer 6

synapse

Question 7

Is each molecular site, within the transduction cascade (chemical and electrical), a potential site for malfunction associated with mental illness and possible targets for psychotropic drugs?

Answer 7

Any site of the transduction cascade has potential for being a site for future psychotropic drugs.

Question 8

Stahl explains that signal transduction cascades are like the “Pony Express” – know what he means by this

Answer 8

signal transduction cascades triggered by chemical neurotransmission involves numerous molecules, starting with nerotransmitter first messenger, and proceeding to second, third, fourth, and more messengers.
He means that the message is handed off between chemical messengers (riders )from one destination to the end.

Question 9

Three sequential “molecular pony express” routes include:

Answer 9

1. A presynaptic neurotransmitter sythesis route from presynaptic genome to the synthesis and packaging of neurotransmitter and supporting enzymes and receptors.
2. A postsynaptic route from receptor occupancy through second messengers all the way to the genome, which turns on postsynaptic genes.
3. Another postsynaptic route starting from the newly expressed postsynaptic genes transferring information as a molecular cascade of biochemical consequences throughout the postsynaptic neuron.

Question 10

What are the two ultimate targets of signal transduction?

Answer 10

Phosphoproteins and Genes

Many of the intermediate targets along the way to the gene are phosphoproteins.

Question 11

What is a phosphoprotein?

Answer 11

A phosphoprotein is a protein that has phosphate group bound to it.

Question 12

What is the ultimate cellular function that neurotransmission often seeks to modify?

Answer 12

Gene expression is the ultimate cellular function that neurotransmission often seeks to modify either turning genes on or off.

Question 13

Neurotrophins trigger an important signal transduction pathway that does what?

Answer 13

Neurotrophins and related molecules leads to activation of enzymes that are mostly kinases, one kinase activating another until finally one of them phosphorylates a transcription factor in the cell nucleus and starts transcribing genes.

Question 14

Stahl discusses that signal transduction pathways may be responsible for what?

Answer 14

Functions by signal transduction pathways include synaptogensis, strengthening of a synapse, neurogenesis, apoptosis, increasing or decreasing the efficiency of information processing in cortical circuits, to behavioral responses such as learning, memory, antidepressant responses to antidepressant administration, symptom reduction by psychotherapy and possibly even the production of a mental illness.

Question 15

How many genes does the human genome contain? And with how many base pairs of DNA? On which chromosomes?

Answer 15

It is estimated that the human genome containg approximately 20,000- 30,000 genes located within 3 million base pairs of DNA on 23 chromosomes.

Question 16

What are elements of gene activation?

Answer 16

The regulatory region of the gene has an enhancer element and a promoter element which can initiate gene expression with the help of transcription factors.

Question 17

How many regions do most genes have? What do these regions do?

Answer 17

Most genes have two regions: a coding region and a regulatory region with enhancers and promoters of gene transcription. The coding region is the direct template for making its corresponding RNA. This DNA can be transcribed into its RNA with the help of an enzyme called RNA polymerase, However, RNA polymerase must be activated or it won’t work.

Question 18

The four most important signal transduction cascades include what?

Answer 18

G-protein linked systems, ion channel linked systems, hormone linked systems, and neurotrophin linked systems.

Question 19

Epigenetic control over whether a gene is read (i.e., expressed) or is not read (i.e., silenced), is achieved by modifying the structure of ____________.

Answer 19

Chromatin in the cell nucleus

Question 20

What do presynaptic neurons do?

Answer 20

Presynaptic neurons store and reuptake neurotransmitters. They also release neurotransmitters.

Question 21

Do psychotropic drugs have many mechanisms of action that target specific molecular sites that have profound effects on neurotransmission?

Answer 21

There are over 100 essential psychotropic drugs in use but there are only a few sites of action for all these therapeutic agents. Specifically, about a third of psychotropic drugs target one the the transporters for a neurotransmitter: another third target receptors coupled to G proteins: and perhaps only 10% target enzymes.

Question 22

What do postsynaptic neurons receive?

Answer 22

postsynaptic neurons have receptors for neurotransmitters

Question 23

What percent of Psychotropic drugs target receptors coupled to G proteins?

Answer 23

1/3 or 33%

Question 24

What percent of psychotropic drugs target enzymes?

Answer 24

10%

Question 25

What is the name of the hepatic and gut drug metabolizing system that pharmacokinetic actions are mediated through?

Answer 25

Cytochrome P450 (CYP) enzyme system

Question 26

What is the unique presynaptic transporter for serotonin?, norepeinephrine?, dopamine?

Answer 26

Serotonin=SERT
Norepinephrine=NET
Dopamine=DAT

Question 27

What is the name of the energy that transports neurotransmitters into the presynaptic neuron?

Answer 27

Adenosisn triphosphatase (ATPase)
It is an enzyme sometimes called the "sodium pump" that creates the downhill gradient for sodium by continuously pumping sodium out of the neuron.

Question 28

Which gene families assist transporters?

Answer 28

SLC6, SLC1, SLC17, SLC18, SLC 32

Question 29

What produces a conformational change in the G-protein-linked receptor that turns on the synthesis of the second messenger to the greatest extent possible?

Answer 29

Agonists are thought to produce a conformational change in G-protein linked receptors that leads to full receptor activation and thus full signal transduction (the action of a full agonist). In the absence of agonist, this same conformational change may still be occurring at some receptor systems, but only at very low frequency. This is referred to as constitutive activity, which may be present especially in receptor systems and brain areas where there is high density of receptors.

Question 30

What are the 5 most important cytochrome P450 enzymes for antidepressant drug metabolism?

Answer 30

CYP 1A2, 2D6, 2C9, 2C19, and 3A4 (family, subtype, and gene product)

Question 31

What CYP450 enzyme affects 5-10% of Caucasians?

Answer 31

CYP 2D6

Question 32

20 % of Asians may have reduced activity of which CYP450 enzyme?

Answer 32

2C19

Question 33

Know what Stahl has to say about smoking tobacco and the metabolism of certain antipsychotics.

Answer 33

The 1A2 enzyme can be increased by smoking, When patients smoke, any substrate of 1A2 may have its blood and brain levels fall and require more dosage. Also, patients stabilized on an antipsychotic dose who start smoking may relapse if the drug levels fall too low. Cigarette smokers may require higher doses of 1A2 substrates than nonsmokers.

Question 34

What do the most important ion channels in psychopharmacology regulate?

Answer 34

Ligand gated ion channels and voltage sensitive ion channels.

Question 35

What opens ligand-gated ion channels, ionotropic receptors, and ion-channel-linked receptors?

Answer 35

A neurotransmitter, drug, or hormone that binds to a receptor is sometimes called a ligand (literally: trying) Thus, ion channels linked to receptors that regulate their opening and closing are often call ligand gated ion channels. Since these ion channels are also receptors thye are sometimes also call ionotropic receptors or ion channel linked receptors .

Question 36

What opens voltage sensitive, or voltage-gated ion channels?

Answer 36

An electrical impulse in a neuron, also known as the action potential, is triggered by summation of the various neurochemical and electrical events of neurotransmission
In short : charge opens them.

Question 37

What are many ligand-gated ion channels assembled from 5 protein subunits called?

Answer 37

Pentameric ligand gated ion channels

Question 38

Which receptors are typical for pentameric subtype structures?

Answer 38

This pentameric structure is typical for GABA(a) receptors, nicotinic cholinergic receptors, serotonin 5HT3 receptors, and glycine receptors.

Question 39

Know what ionotropic receptors or ion-channel-linked receptors are and what affect they have on psychotropic drugs.

Answer 39

Ion-channel linked receptors act along an agonist spectrum, and drugs have been described that can produce conformational changes in these receptors to create andy state from full agonist to partial agonist, to silent antagonist, to inverse agonist

Question 40

What are allosteric modulators? and what do they do?

Answer 40

There are molecules that can bind to sties different from where neurotransmitters bind. These sites are called allosteric (other site) and ligands that bind there are called allosteric modulators. Allosteric modulators only work in the presence of the neurotransmitter.
2 forms: those that boost what the neurotransmitter does (PAMs= Positive Allosteriic modulators) and those that block what the neurotransmitter does (NAMs= Negative Allosteric Modulators)

Question 41

What do voltage sensitive ion channels require to work?

Answer 41

Ionic charge or voltage potential. An impulse to cause an action potential

Question 42

Know the description of a voltage sensitive sodium channel and a voltage sensitive calcium channel

Answer 42

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