15.1.1 Mood Disorders 2

Question 1

Blocking histamine produces _____. Blocking acetylcholine leads to ___ ____ and difficulty urinating. Blocking sodium channels causes ____ irregularities.

Answer 1

drowsiness : dry mouth : heart

Question 2

The ____ ____ ____ ____ (SSRIs) are similar to tricyclics but specific to the neurotransmitter serotonin. For example, fluoxetine (trade name Prozac) blocks the reuptake of serotonin.

Answer 2

selective serotonin reuptake inhibitors

Question 3

Several new drugs are serotonin ____ reuptake inhibitors (SNRIs).

Answer 3

norepinephrine

Question 4

____ ____ ____ (MAOIs) (e.g., phenelzine, trade name Nardil) blocks the enzyme monoamine oxidase (MAO), a presynaptic terminal enzyme that metabolises catacholamines and serotonin into inactive forms.

Answer 4

Monoamine oxidase inhibitors

Question 5

When MAOIs block this enzyme, the presynaptic terminal has more of its ____ available for release.

Answer 5

transmitter

Question 6

People using MAOIs must avoid foods containing ____ – including cheese, raisins, and many others – because a combination of tyramine and MAOIs increases blood pressure.

Answer 6

tyramine

Question 7

The ____ ____ are a miscellaneous group – everything other than the types just discussed. One example is bupropion which inhibits reuptake of dopamine and to some extent norepinephrine but not serotonin.

Answer 7

atypical antidepressants

Question 8

In addition, many people use _______ for depression, an herb.

Answer 8

St John’s Wort

Question 9

St John’s Warts effectiveness appears to be about the ____ as that of a standard antidepression drugs.

Answer 9

same

Question 10

However, it has a potentially dangerous ____: all mammals have a liver enzyme that breaks down plant toxins. St John’s wort increases the effectiveness of that enzyme.

Answer 10

side-effect

Question 11

Increasing the breakdown of toxins sounds like a good thing, but the enzyme also breaks down most ____. Therefore taking St John’s wort decreases the effectiveness of other drugs you might be taking.

Answer 11

medicines

Question 12

The commonly used antidepressants increase the presence of serotonin and other ____ at the synapse, and so it might seem that the problem with depression is too little of the neurotransmitters.

Answer 12

neurotransmitters

Question 13

However, the story is not that simple. So far as we can tell from blood metabolites, people with depression have approximately normal levels of release of ____.

Answer 13

neurotransmitters

Question 14

Furthermore, it is possible to decrease serotonin levels suddenly. For most people, this decrease in serotonin does not ____ any feelings of depression.

Answer 14

provoke

Question 15

Furthermore, given that different drugs act in different ways on different neurotransmitters, wouldn’t you expect some of them to be more effective than others? So far as we can tell, all of them are about equal in ____.

Answer 15

effectiveness

Question 16

The ____ ____ of effects poses an additional threat to any explanation in terms of neurotransmitters: antidepression drugs produce their effects on neurotransmitters in the synapses within minutes to hours, depending on the drug, but people need to take a drug for two more weeks before they experience any mood elevation.

Answer 16

time course

Question 17

This ____ of ____ strongly suggests that increasing the levels of neurotransmitters at synapses does not explain the benefits of the drugs.

Answer 17

delay of benefits

Question 18

Today, much research attention focuses on ____. ____ aid in the survival, growth, and connections of neurons.

Answer 18

neurotrophins

Question 19

Most people with depression have lower than average levels of a neurotrophin called ____ ____ ____ (BDNF) that is important for synaptic plasticity, learning, and proliferation of neurons in the hippocampus.

Answer 19

brain-derived neurotrophic factor

Question 20

As a result of low BDNF, most people with depression have a smaller than average hippocampus, impaired learning, and reduced production of new ____ ____.

Answer 20

hippocampal neurons

Question 21

Prolonged use of anti-depressant drugs generally increases BDNF production and improves learning and formation of new neurons. This process takes ____.

Answer 21

weeks

Question 22

Apparently BDNF by itself does not automatically ____ ____, but it helps by facilitating new learning that builds new synapses and removes many old ones.

Answer 22

elevate mood

Question 23

That mode of action by BDNF explains why antidepressants help people in depression – who might profit from substituting new thoughts for old ones – but failed to elevate mood for ____ ____.

Answer 23

normal people

Question 24

In most cases, depression occurs in episodes. That is, even without treatment, many people recover within a few ____.

Answer 24

months

Question 25

Furthermore, giving someone a medication produces an ____ of ____, thereby enhancing the probability of recovery, even if the medication itself is ineffective.

Answer 25

expectation of improvement