Psychopharm Part I

Question 1

Defining properties of neurotransmitters?

Answer 1

1) synthesized and released from neurons; 2) released from nerve terminals in a chemically or pharmacologically identifiable form; 3) interact with postsynaptic receptors and brings about the same effects as are seen with stimulation of the presynaptic neuron; 4) interaction with the postsynaptic receptor displays a specific pharmacology; 5) actions are terminated by active processes

Question 2

Major receptor subtypes?

Answer 2

1. Ionotropic 2. G-protein coupled (GPCRs) 3. Receptor tyrosine kinases 4. Nuclear receptors

Question 3

Ionotropic receptors

Answer 3

• relatively self-contained in structure - message takes the form of transmembrane ion fluxes

Question 4

GPCRs

Answer 4

multicomponent in nature and generate intracellular second messengers

Question 5

receptor tyrosine kinases and phosphatases

Answer 5

contain intrinsic enzymatic activity

Question 6

Nuclear receptors

Answer 6

1. cytoplasmic 2. translocate to the nucleus to directly regulate transcription (gene expression) 3. activated by lipophilic molecules (often hormones) that enter the cell

Question 7

Autoreceptors

Answer 7

located on neurons that produce the endogenous ligand for that particular receptor (e.g., a serotonergic receptor on a serotonergic neuron)

Question 8

Heteroreceptors

Answer 8

present on neurons that do not contain an endogenous ligand for that particular receptor subtype (e.g., a seroto-nergic receptor located on a dopaminergic neuron).Definition

Question 9

Types of autoreceptors

Answer 9

1. Somatodendritic (on cell bodies, regulate firing rate of neurons) 2. Nerve terminal (regulate amount of neurotransmitter released per nerve impulse)

Question 10

What kind of receptor is the glutamate receptor (e.g. NMDA)?

Answer 10

Ionotropic

Question 11

What kind of receptor is the GABA receptor?

Answer 11

Ionotropic

Question 12

What kind of receptor is the ACh receptor?

Answer 12

Ionotropic

Question 13

The 3 modes of regulation of GPCRs?

Answer 13

1. Desensitization (homologous and heterologous) 2. Downregulation 3. Trafficking

Question 14

50% of 5HT neurons are in…

Answer 14

the dorsal raphe

Question 15

Presynaptic regulation of 5HT is via which receptors?

Answer 15

somatodendritic 5-HT1A and autoreceptors 5-HT1B and 5-HT1D

Question 16

Which aminoacid is the precursor for 5-HT?

Answer 16

L-Tryptophan

Question 17

What is the rate-limiting step in the production of serotonin?

Answer 17

Converting from tryptophan to 5-hydroxytryptophan by *tryptophan hydroxylase*

Question 18

Which enzyme converts 5-hydroxytryptophan to serotonin?

Answer 18

amino acid decarboxylase

Question 19

What is the metabolite of serotonin?

Answer 19

MAO converts it to 5-HIAA (5-hydroxyindoleacetic acid)

Question 20

tryptophan depletion triggers depressive relapse in patients treated with ____(1)____ but NOT in those treated with ____(2)_______

Answer 20

1) SSRIs 2)NRIs

Question 21

5-HT1A receptor is downregulated by…

Answer 21

adrenal steroids but NOT 5-HT

Question 22

Which autoreceptors are present on the presynaptic terminal of 5HT neurons?

Answer 22

5-HT1B and 5HT1D

Question 23

The ratio of D2/5-HT2 blockade confers…

Answer 23

atypicality in antipsychotics

Question 24

5HT2 receptors are downregulated by…

Answer 24

chronic administration of antidepressants

Question 25

5HT2 receptors are upregulated by…

Answer 25

ECT