355 continued

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355 continued
2012-03-09 12:58:41

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  1. What is pharmacodynamics?
    Collective name for the factors that affect the relationship between a drug and its target receptors, such as affinity and efficacy.
  2. True or False: Understanding DRCs reveals many aspects of a drugs activity and is one of the main tools for understanding pharmacodynamics.
  3. Why are DRCs useful for gaining information about drugs?
    • 1. allows us to compare drug potencies
    • 2. reveals effective dose range
    • 3. reveals if drug is binding to more than 1 receptor.
    • 4. tells us which drug is safer for use
  4. What is drug tolerance? Why does it occur?
    Drug tolerance is a condition in which with repeated exposure to a drug comes less responsiveness to a constant dose. So, continuous doses have a decreasing effect. Tolerance occurs because our bodies are adaptable-we adapt to environmental changes that in the case of drugs, can change our bodys chemical environment.
  5. How does drug tolerance develop?
    Either by metabolic tolerance; repeated exposure to a drug causes metabolic machinery of the body to be more efficient at removing it. Or, functional tolerance; decrease responding to a drug after repeated exposures due to up or down regulation of receptors (from neuronal sensitivity)
  6. Why does neuronal sensitivity occur? (functional tolerance)
    receptor regulation (changing amount of available receptors in the membrane)
  7. What is cross tolerance? What is an example?
    Cross tolerance refers to tolerance to a drug that generializes to that drugs category. For example, people who develop a tolerance to morphine often develop a tolerance to other drugs within the opiate category (e.g. heroin).
  8. What are withdrawal symptoms?
    caused by tolerance, withdrawal symptoms are unpleasant symptoms associated with stopping the drug.
  9. Can the opposite effect of tolerance occur? What is this called?
    Yes, this is called sensitization in which the drug repsonse becomes stronger with repeated treatments rather than weaker. Thought to contribute to drug cravings.
  10. What are drugs that act on what is bioavailable?
    Drugs that increase in concentration in the body based on what is bioavailable (free to act on the target tissue and not bound to other processes). This means that drugs have faster more efficient effects. Examples include nicotine and intravenous drugs.
  11. What are drugs that take the longer route, requiring biotransformation? What is biotransformation?
    Drugs that take the "longer route" are those that take longer to have effect, such as those drugs ingested orally. The duration of the drug effect is determined by how it is metabolized for example, via the kidneys or liver. Biotransformation can create unwanted side effects.
  12. What is pharmacokinetics?
    name for all the factors that affect the movement of a drug into, through and out of the body.
  13. What is the blood brain barrier?
    mechanism that makes the movement of substances from blood vessels into brain cells more difficult than exchanges in other body organs, thus affording the brain greater protection from exposure to some substances found in the blood
  14. What do neuromodulators do?
    Affects the receptor response to a transmitter or release of a neurotransmitter
  15. What is an example of a neuromodulator? What does it block?
    Caffeine is an example of a neuromodulator. It blocks the adenosine receptor which is responsible for altering synaptic activity.
  16. What is an autoreceptor?
    A receptor for the synaptic transmitter located in the presynaptic membrane and tells the axon terminal how much transmitter has been released. Adenosine is an autoreceptor.
  17. What is a transporter?
    Specialized receptors in the presynaptic membrane that recognize NT molecules and return them back into the presynaptic neuron for reuse. Some drugs work presynaptically. For example, antidepressants, inhibit the reuptake of serotonin so it has a prolonged effect.
  18. What is degradation?
    The chemical breakdown of a neurotransmitter into inactive metabolites
  19. What receptor do antipsychotics act upon/as? Antagonists or agonists?
    Antagonists of dopamine receptor D2 (both typical and atypical)
  20. How is serotonin impacted in the use of antidepressants or SSRIs?
    the serotonin is kept in the synapse as reuptake is blocked by the SSRI exogenous drug. For earlier antidepressants, MAO is accumulated at the synapse to improve mood and tricyclics increase serotonin and norepinephrine content in the synapse to combat depression
  21. Where do anxiolytics act (benziadepine agonists) ?
    They act on GABAA receptors. They produce more post synaptic potentials of inhibition (bc GABA is inhibitory) than GABA would alone.
  22. What is an orphan receptor?
    A receptor for which an endogenous ligand has been identified. Benzodiazepines bind to orphan receptors.
  23. What is Allopregnanolone?
    a naturally occuring steroid that works in the same way benzodiazepines do on GABA receptors.
  24. What is a neurosteroid?
    Steroids produced in the brain
  25. Which neurotransmitters are affected by alcohol?
    Dopamine pathways (associated with the euphoria produced by low levels of alcohol) and GABA. With a few drinks of alcohol, GABAa receptors become more sensitive to GABA. This is the cause of social disinhibition.
  26. Alcohol is biphasic. What does this mean?
    This means that initially alcohol has stimulant like effects which are then followed by a more prolonged depressant phase.
  27. What are examples of analgesics? (exogenous)
    morphine, heroin, opium
  28. What are examples of endogenous opiods?
    enkephalins, endorphins, dynorphins
  29. What types of receptors are opiod receptors?
  30. What is THC ( in marijuana)?
    The major active ingredient in marijuana.
  31. What is an endocannabinoid?
    an endogenous ligand of cannabinoid receptors; thus an analog of marijuana that is produced by the brain.
  32. What is anandamide?
    An endogenous substance that binds to the cannabinoid receptor molecule
  33. What is khat?
    an african shrub, acting as a stimulant when chewed.
  34. What is nicotine?
    A compound found in plants including tobacco, that acts as an agonist on a large class of cholinergic receptors.
  35. What is cocaine?
    a drug of abuse deriving from the cocoa plant, that acts by potentiating catecholamine stimulation (dopamine, epinephrine, norepinephrine).
  36. What is an amphetamine?
    A stimulant like cocaine which recemples the catecholamine transmitters (epinephrine, norepinephrine, dopamine).
  37. What is cocaine and amphetamine regulated transcript (CART)?
    a peptide produced in brain when amphetamine or cocaine is injected into the VTA. Also associated with appetite control.
  38. What are hallucinogens?
    A class of drugs that alter sensory perception and produce peculiar experiences.
  39. What is LSD? What neurotransmitter does it resemble?
    a type of hallucinogen. Serotonin and acts on serotonin receptors.
  40. What is phencyclidine? (PCP) why is it classified as a dissociative drug?
    an anesthetic agent that is also a psychedelic drug. Classified as a dissociative drug because it produces feelings of depersonalization and detachment from reality.
  41. What is Ketamine and MDMA (ectasy)?
    Ketamine is a dissociative drug that acts as a NDMA receptor antagonist (blocks glutamate). MDMA is a hallucinogenic amphetamine.
  42. What is the nucleus accumbens?
    A region of the forebrain that recieves dopaminergic innercation from the VTA.