Week 7 - Nicotine + Caffeine Flashcards
What are the biggest killers attributable each year to smoking?
Lung Cancer, Ischemic Heart Disease and Pulmonary Disease
What is tobacco? What is nicotine?
Tobacco refers to leaves from Nicotiana plants. Nicotine is the psychoactive ingredient found in tobacco.
What is flue-cured tobacco? *Cigar smokers may be less likely to inhale tobacco smoke since this tobacco is not flue-cured
Flue-cured tobacco is found in cigarettes. It involves venting heat through a metal flue onto tobacco leaves. It reduces the pH (by converting starches to sugars) of smoke, making the smoke less harsh and allowing for faster absorption of the nicotine.
What is smoking tobacco? What are some examples of smokeless tobacco?
Tobacco that is smoked without tar???????
What is tar?
The burned residue of tobacco carries all the active ingredients.
Why do cigs have reach peak absorption faster than e-cigs?
As nicotine from cigs is absorbed from mucous membranes in the lungs (lungs have large SA) and nicotine from e-cigs is absorbed from mucous membranes in the mouth, throat, and stomach?
Why does nicotine easily pass through the BBB?
Nicotine is lipid-soluble
In what tobacco products is the freebase form of nicotine used?
The freebase form of nicotine is lipid soluble and hence allows for faster absorption through the mucous membrane of the mouth, as well. Smokeless and dissolvable tobacco products have the most of this form presumably.
What is the half-life of nicotine?
2 hours?
Why do chronic smokers have a 30% faster elimination rate of nicotine than nonsmokers?
As chronic smokers have acquired sensitization to nicotine??
How much nicotine is metabolized? What are active metabolites of nicotine and how do they work?
80-90%. Cotinine works similarly to nicotine???
Explain the pharmacogenetics of nicotine metabolism?
TEXTBOOK
What is nicotine’s mechanism of action on receptors? What receptors does nicotine act on?
Nicotine acts on nicotinic receptors (ionotropic receptors. It works as a cholinergic agonist by binding to these receptors and causing an influx of cations (Ca2+, Na+, K+)
What does it mean when a neuron or receptor is called cholinergic?
Neurons that release acetylcholine? Receptors that bind to acetylcholine.
What are the types of cholinergic receptors?
Muscarinic receptors (there are 5 of these) and nicotinic receptors. *Muscarinic receptors are metabotropic and nicotinic receptors are ionotropic.
How is acetylcholine made? How is acetylcholine broken down?
- Acetyl coA + choline (mediated by choline transferase.
2. Cholinesterase breaks down acetylcholine to acetic acid + choline
How does acetylcholine travel within the neuron and synapse?
REVIEW
What does the interconnected cholinergic system refer to?
Some cholinergic neurons just act on one system???
Where are cholinergic neurons particularly present?
Basal ganglia, pons, tegmental nucleus, hippocampus and
What main regions do cholinergic neurons innervate?
Cerebral cortex, brain stem *within the brain stem itself????
What is one of the main drivers of the addictive nature of nicotine?
the dopamine pathways it acts on. Acts on the reward center???
Where are nicotinic neurons particularly present in the brain?
neuromuscular junctions?
What is one of the biggest physiological indicators of nicotinic neurons being activated?
Increased activity of the sympathetic nervous system
What is functional antagonism? How do nicotinic receptors become desensitized?
Nicotine inactivates nicotinic receptors longer than it activates them so that over time more nicotine use results in less activation of these receptors. This is why the receptors become desensitized.
What is acute tolerance? How does functional antagonism explain this?
The fact that at one go the nicotinic receptors inactivate receptors for longer than they are actually activated (ie. it antagonizes its own behavior on the receptors)
Explain some of the physiological, behavioral and subjective effects of nicotine: **
Physiological: slower HR
Behavioral:
Subjective effects: relaxed feeling
How does chronic tolerance happen for nicotine? **
I don’t actually know…
How does tobacco lead to adverse side effects associated with nicotine? **
a
What is nicotine abstinence syndrome and how is it characterized?
a
Explain psychotherapeutic treatments to nicotine addiction
a
Pharmacological Treatment: How does nicotine replacement therapy work?
a
Pharmacological Treatment: How does nicotinic-receptor agonism work?
a
Pharmacological Treatment: How do antidepressant drugs work?
a
What are the xanthines?
A chemical class that includes caffeine, theobromine, theophylline.
Where is caffeine found? What type of drug is caffeine?
Coffee, tea, cacao leaves. Caffeine is psychostimulant.
How do the acids in coffee help it get absorbed? Why is 100% of caffeine absorbed?
the acids allow for faster absorption??????
How is caffeine metabolized? Why does elimination for caffeine vary so widely?
Caffeine is metabolized in the liver by the enzyme CYP-1A2. Elimination of caffeine is highly dependent on one’s genetic makeup.
Active metabolites of caffeine are xanthines. What are the active metabolites of this drug?
a
What receptors does caffeine act on? What are the different subtypes of these receptors?
Adenosine receptors - A1, A2a, A2b, A3 (purinergic G-protein coupled receptors).
Where are the two types of adenosine receptors predominantly found?
a
How does adenosine influence cholinergic neurons and dopamine neurons?
Inhibits both types of receptors.
What is caffeine’s mechanism of action?
a
How do adenosine levels change in synapses in non-caffeine users and those who habitually use caffeine?
a
Why (may) caffeine users be tired?
Research suggests that it is a withdrawal effect of habitual
How does caffeine affect dopamine?
a
What is caffeinism?
a
What are the effects of caffeine intoxication?
a
What are the effects of caffeine withdrawal?
a
What are the psychostimulant effects of caffeine?
a
What is the greatest amount of freebase nicotine that can be absorbed and when does this happen?
50% of nicotine. at pH 8.02
What is another compound in tobacco that may facilitate nicotine’s effects and how does this compound work?
MAO inhibiter?????
