Final Flashcards
The following 3 monoamines are known to project to which location/system in the brain?
1. Serotonin (5HT) (raphe nucleus)
2. norepinephrine (NE) (locus coeruleus)
3. dopamine (DA) (VTA)
The limbic system and the forebrain (aka MEDIAL FOREBRAIN BUNDLE)
What stress hormone is released from the adrenal glands, and is known to travel to the hippocampus, amygdala, and the prefrontal cortex?
Cortisol
Which brain region secretes corticotropin-releasing hormone (CRH)?
Hypothalamus
Which brain region secretes adrenocorticotropic hormone (ACTH)
Anterior pituitary
Which brain region produces glucocorticoid(stress) hormones (AKA cortisol)?
Adrenal cortices
Which stress hormones can act back on the hypothalamus and pituitary (to suppress CRH and ACTH production) in a negative feedback cycle?
Glucocorticoids
How do first generation monoamine oxidase inhibitors (MAOIs) work to increase serotonin in the brain? BONUS if you can name the two enzymes that destroy monoamines
MAOIs increase 5HT by degrading monoamine oxidase enzymes that breakdown 5HT
Bonus: MAO-A degrades 5HT, NE and DA and MAO-B degrades DA only
How do first generation tricyclic antidepressants (TCAs) work to increase MAs?
TCAs block reuptake transporter proteins on 5-HT and NE neurons
Clonazepam, diazepam and lorazepam are examples of what type of anxiolytic medications?
Benzodiazepines
Amobarbital and pentobarbital are examples of what type of anxiolytic medications?
Barbiturates
Imipramine and Amitriptyline are examples of what class of antidepressant medications?
TCAs
Escitalopram and citalopram are examples of what class of antidepressant medications?
SSRIs
Rasagiline and selegiline are examples of what class of antidepressant medications?
MAOIs
Duloxetine and venlafaxine are examples of what class of antidepressant medications?
SNRIs
Marijuana and hashish are forms of which class of drugs?
Cannabis
delta-9-tetrahydrocannabinol or △-9-THC is the main ingredient of which drug?
Cannabis
What is the most common cannabinoid in the Cannabis plant?
delta-9-tetrahydrocannabinol or △-9-THC
How many cannabinoids are known to exist in Cannabis?
85
What are the 3 prevalent chemicals in Cannabis?
delta-9-tetrahydrocannabinol or △-9-THC, cannabinol (CBN) and cannabidiol (CBD)
What is the name of cannabinoids that come from a cannabis plant?
Phytocannabinoids
What is the name of cannabinoids that are endogenous to the body?
Endocannabinoids
What is the abbreviation for anything that binds to a cannabinoid receptor?
CB
What is the name for a cannabinoid that is synthesized or made in a lab?
Synthocannabinoid
What is the psychoactive and appetite inducing chemical in cannabis?
THC
What is the non psychoactive and possibly therapeutic/anxiolytic/antipsychotic chemical in cannabis?
CBD
What is the abbreviated term for the drug 3,4-methylenedioxy-methamphetamine?
MDMA
What is a drug formulation?
A combination of excipients and active ingredients
What is the term for an observable action or state that occurs in response to a stimuli?
A behaviour
What is the name class of a drug that has not been patented, and is the common name of the chemical makeup?
Generic name
What is the name for a range of doses plotted on a graph, with the dose indicated on the horizontal axis and the effect on the vertical axis?
Dose response curve
What is measured on each axis of a DRC?
Y-axis: Typically demonstrates the dose mg/kg.
X-axis: Generally demonstrates the effect change in a % of animals according to the dose administered
What type of curve is the usual result of dose responses?
A continuous curve
Define ED50.
Mean therapeutic (effective) dose for 50% of the sample
Define LD50.
Mean lethal dose for 50% of the sample
How do you calculate the therapeutic index of a drug?
LD50/ED50
What can the therapeutic index of a drug tell us?
The safety of a drug
What does a HIGH TI signify?
The drug is very safe
What does a LOW TI signify?
The drug is not safe
How are potency and effectiveness different? Define potency, then define effectiveness.
Potency is the amount of drug needed to produce ANY given effect.
Effectiveness is whether the drug produces a given effect at its target location.
Name TWO ways drugs can be agonistic. There are 6 total ways.
Increasing synthesis of a molecule
Destroying degrading enzymes
Increase release of molecule
Inhibit autoreceptors
Binding to postsynaptic receptors
Blocking deactivation
Name TWO ways drugs can be antagonistic. There are 5 total ways. Think back to agonistic effects.
Blocking synthesis of a molecule
Increasing vesicle leaks
Blocks release
Activating autoreceptors
Blocking receptors
A drug that blocks NT synthesis by destroying enzymes is an example of an agonist or antagonist?
Antagonist
A drug that binds to an autoreceptor leaves more neurotransmitters in the cleft is an example of an agonist or antagonist?
Agonist
What are the two categories of drug effects?
Primary effects and side effects
The effect for which a drug is taken (i.e. morphine for pain) is known as what?
Primary effect
Any other effect that results from the drug (i.e nausea and vomiting with morphine) is known as what?
Side effect
Name the 4 routes of administration.
Parenteral
Inhalation
Per Oral
Transdermal
Give TWO examples of parenteral administration.
Intramuscular injection (through the muscle)
Intraperitoneal injection (through the abdominal cavity)
Intravenous (directly into the blood stream)
Subcutaneous injection (into the fatty layer of skin)
Give TWO examples of inhalation administration.
Gasses, smokes and solids
Give TWO examples of per oral administration.
Taken by mouth and swallowed
Buccal membranes (think chewing tobacco)
Suppositories (into the rectum)
Give TWO examples of transdermal administration.
Creams or patches.
Describe the route of absorption of parenteral administration.
Absorbed into the circulatory system
Describe the route of absorption of inhalation administration.
Capillaries in the lungs or the nasal cavities
Describe the route of absorption of per oral administration.
Capillaries in the intestines
Describe the route of absorption of transdermal administration.
Determined entirely by the lipid solubility of the drug, goes into the blood eventually.
Name one advantage to parenteral administration.
Blood is constantly circulating and being replaced by new blood with a low concentration of drug→ more will be absorbed as the blood circulates through the area
Name one advantage to per oral administration.
Significant absorption will take place even if only a small percentage of molecules is not ionized
Name one advantage to inhalation administration.
Rapid absorption without passing through the liver
Name one advantage to transdermal administration.
Can be administered at a controlled rate which maintains stable blood levels of a drug
Name one disadvantage to per oral administration.
Drugs taken with food slows absorption
→ empty stomach = fast absorption
Depends on lipid solubility as well (how well the drug dissolves in fats)
Name one disadvantage of transdermal administration
Very slow.
Name TWO of the 6 factors affecting absorption.
Lipid solubility
Ion trapping
Blood-brain barrier
Transport mechanisms
Placenta
Protein binding
Explain TWO of the 6 factors in how they affect absorption.
Choose from the following:
1. Lipid solubility
2. Ion trapping
3. Blood-brain barrier
4. Transport mechanisms
5. Placenta
6. Protein binding
- Drugs concentrate in body fat outside CNS
Pass through membranes easily - Drugs get trapped on one side of membrane that has different pH
- Special cells in the central nervous system that wrap themselves around the capillaries and block the pores through which substances normally diffuse
- Active transport mechanisms concentrate cells on one side of the membrane.
Passive transport involves a large protein molecule creating a channel for a non-ionized cell to pass through the cell membrane - Similar to BBB
- Large proteins can’t diffuse because they are too big to pass through pores of capillaries
What are two factors that are involved in eliminating a drug?
Metabolism and excretion
Where does metabolism occur in the body?
The liver (mainly)
Where do excretion mechanisms occur?
The kidneys and the nephron
What occurs during the process of metabolism?
Enzymes act as a catalyst to modify molecules to form new substances useful to the body
What happens during excretion? Specifically, what do the kidneys and the nephron do?
Kidney→ filtering everything out of the blood and then allowing selective reabsorption of what is required.
Nephron→ reabsorption→ accomplished by the mechanisms of distribution
Name and explain TWO factors that alter metabolism.
- Stimulation of Enzyme Systems
- Metabolic tolerance
- The body expects the drug to be there
(because of past experience) so
produces compensatory enzymes to
process faster. - Depression of Enzyme Systems
- Competition for enzymes or depressing
enzymes
- Two drugs that use the same enzyme to
process can make for the drugs to not be
properly processed - Age
- Lack of enzymes/underdeveloped or too
old
- Enzyme systems are not fully functional
at birth
- Enzyme systems also deplete with age - Species
- Different enzymes
- Livers of different species process
substances differently
What is the therapeutic window of a drug? Is a larger therapeutic window better?
The therapeutic window of a drug is the range of concentration of a doseage between the ED50 and the LD50. The larger the therapeutic window the better.
Name two examples of barbiturates.
Amobarbital
Pentobarbital
Name two examples of benzodiazepines.
Diazepam
Lorazepam
Clonazepam
What are the routes of administration of anxiolytics?
If long-term→ oral medications
If needed immediately→ intravenous
Are anxiolytic medications weak acids, or weak bases?
Weak acid (pKa 3.5) → fast absorption in the stomach
Are antidepressant medications weak acids, or weak bases?
Weak acid (pKa 3.5) → absorbed in the stomach
Are methylxanthines weak acids, or weak bases?
Weak base (pKa 0.5) → SLOW in the stomach, fast in the intestines.
Are stimulants weak acids, or weak bases?
Weak base → but HIGH pKa of 9-10 → slow absorption
Are opioids weak acids, or weak bases?
Weak base→ BUT pKa of 8 → not rapid absorption
How are anxiolytics excreted in the body?
Biphasic excretion.
- Redistribution (2-10 hr half life) (distributes from bloodstream to fat)
- THEN Slow release (1-2 day half life) (distributes from the fat to body tissues)
What are some effects of barbiturates on the body?
Sleepiness, mild euphoria, decreased anxiety.
Decreased blood pressure and breathing rate
High doses→ lack of coordination
What are some effects of benzodiazepines on the body?
Muscle relaxation and headache relief
Ataxia and muscle tremor
What are some positive effects of barbiturates on sleep?
Helps with insomnia
What are some positive effects of benzodiazepines on sleep?
Shorten time it takes to fall asleep, decreases awakenings during the night, and increase sleep time
What are some effects benzodiazepines can have on human behaviour? Think back to the ones on alcohol.
Euphoria and liking for the drug, memory loss, long half-life, increased driving risk
What are the unconditioned behaviours anxiolytics can have on animals?
Taming effect, reduces defensive aggression
Can animals discriminate anxiolytics from placebo and alcohol?
Yes.