Nicotine

Question 1

What are the effects of nicotine

Answer 1

Reinforcing/Rewarding
Behavioral
Cognitive
Autonomic and physiological effects

Question 2

What kind of drug is nicotine

Answer 2

Stimulant; relaxant

Question 3

What is nicotine absorption dependent on?

Answer 3

pH dependent

Question 4

How is nicotine absorbed in acidic conditions?

Answer 4

ionized –> poorly absorbed across membranes

Question 5

How is nicotine absorbed in alkaline conditions?

Answer 5

Non-ionized –> well absorbed

Question 6

How is nicotine absorbed in physiological pH

Answer 6

Nicotine is readily absorbed in pH around 7.3-7.5

Question 7

How is nicotine metabolized

Answer 7

10-20% is excreted
70-80% is turned into cotinine
10% into other metabolites

Question 8

what is the half life of nicotine

Answer 8

2 hours

Question 9

what is the half life of cotinine

Answer 9

19 hours

Question 10

how is nicotine excreted

Answer 10

through the kidneys (urine)
Breast milk

Question 11

How is nicotine excretion affected by pH

Answer 11

Lower pH (acidic conditions) increases the rate of kidney excretion

Question 12

How is nicotine able to act on the autonomic nervous system

Answer 12

Nicotine binds to nicotinic cholinergic receptors

Question 13

What is required of the subunits of cholinergic receptors

Answer 13

at least two subunits have to be alpha

Question 14

what are some important brain structures that nicotine acts on

Answer 14

striatum
amygdala
hypothalamus
substantia nigra; VTA

Question 15

How do different subunit combinations of nAChR affect nicotine

Answer 15

they have differing rates of desensitization and different properties

Question 16

How does nicotine affect the pain response

Answer 16

analgesic effect (increased latency of tail withdrawal)

Question 17

What is the effect of nicotine dependent on

Answer 17

state of the person

Question 18

What is an indirect result of nicotine consumption

Answer 18

increase in norepinephrine levels

Question 19

What is the dual reinforcement model of nicotine

Answer 19

Nicotine is a primary reinforcer but it works but ENHANCING the reinforcing properties of other reinforcing stimuli

Question 20

what happens to the reinforcement enhancing effect of nicotine when drugs that block nicotine receptors are added

Answer 20

the reinforcing effect was blocked showing that nicotine is directly responsible for the phenomenon

Question 21

what is the relationship between the reinforcing stimuli and nicotine

Answer 21

the more reinforcing the stimulus is the greater the enhancement is by nicotine

Question 22

what is different about buproprion

Answer 22

Has the same reinforcement enhancing effect but is not blocked by drugs that block actions of nicotine

Question 23

what is different about varenicline

Answer 23

has reinforcement enhancing effects but also blocks the maximal reinforcing affects of nicotine

Question 24

what is short term tolerance of nicotine

Answer 24

nicotine slowly dissociated from the receptor leading to desensitization (sometimes overnight)

Question 25

what is characteristic of chronic smokers

Answer 25

increased expression of nACh receptors in the brain (longterm desensitization = upregulation)

Question 26

what are some withdrawal symptoms of nicotine

Answer 26

headache, stomach pain, craving, depression, anger/irritability, anxiety, restlessness, poor concentration, insomnia, decreased HeartRate, increased appetite

Question 27

what happens when smokers are given a nicotine antagonist

Answer 27

increased smoking to overcome antagonist

Question 28

what happens when smokers are preloaded with nicotine

Answer 28

decreased smoking

Question 29

what is nesbitt’s paradox

Answer 29

nicotine causes an arousal of brain activity and causes release of NE which activates sympathetic NS but smokers report that smoking “relaxes” them

Question 30

what are some explanations for Nesbitts paradox

Answer 30

Acute nicotine deprivation leads to stress which leads to smoking to normalize their mood