Lecture 19-22 Flashcards
Desomorphine (3)
synthesized from + morphine + high
- synthesized from codeine
- Analog of morphine but more potent and addictive
- Shorter high than heroin (1.5h vs 4-8h)
Streetuse of desomorphine (3)
synthesize + dangerous bc + streetname
- Easy to synthesize (cheap/fast)
- dangerous as it is not purified (contains codeine, gasoline, iodine, red phosphorous, HCl, paint thinner)
- Streetname is Krokodil
The effects of Krokodil:
+ chronic users
- blood vessel degradation
- Blood vessel rupture
- Gangrene (blood flow to an area of tissue is cut off)
- Amputation
- Scaly appearance
- Chronic users dont survice for 2-3 years
History of drugs: Willow Bark (2)
contains + relieves
- Contains salicin, transformed into salicyclic acid (the precursor to aspirin)
- Relive pain and fever
History of drugs: Shamanism (2)
What + example
- healer through trance (“First she goes/falls into a deep trance, and then the spirit voices start to speak through her”), plant-based medicines, in the context of a local religion
- Entheogen: Psychoactive substance used in a religious, shamanic or spiritual context
A shift to more centralized religions resulted in a preiesthood in control of healing, for example (3):
Ex + pages/prescriptions + treats….
- Elbers Papyrus: ancient Egyptian medical document
- 110 pages long containing more than 800 prescriptions
- Waspstrings, crocodile bites, baldness, constipation, headaches, sweaty feet, arthritis, inflammation, heart disease, cancer etc
History of drugs: Middle ages
- Vikings warriors assumed to have ingested mushrooms (Amanita muscaria) which has psychoactive properties or henbane Hyoscyamus niger a atropine (acts as a competitive, reversible antagonist of muscarinic receptors: an anticholinergic drug) resulting in increased energy and wild behaviour in battle
History of drugs: Drug use and witchcraft
- Induced hallucinations and sensation of flying by consuming brews made of mandrake, hebane, and belladonna
History of drugs: Licking toads (2)
What contains + derivative
- Sweat glands contain a powerful hallucinogen (5-MeO-DMT) as well as bufotenine (raises blood pressure and heart rate)
- Both of which are tryptamine derivative
History of drugs: 19th century (3)
2 invention/advances + there was no…..
- Advances in chemistry resulted in the identification and purification of morphine as the active ingredient in opium and cocaine in coca
- Invention of the hpodermic syringe Purified substance to be injected to BS to increase potency
- No drug control laws (Pain+cough syrups for kids have morphine and codeine)
Drug addiction becomes medicalized (3):
3 timelines
- 1870: American Association for the Cure of inebriates
- 1935: Alcoholics Anonymous became popular
- 1950: World Health Organization declares alcoholism a disease
Today we accept the —— model of addiction
disease
What defines addiction (2)
what + the cycle
- A chronic relapsing behavioural disorder
- A compulsive drug seeking and drug use:
1. Craving: Strong urger to take the drug (something in brain changed, neuroadaptivity)
2. Remisssions: Drug-free periods
3. Relapse: Drug use recurs, despite negative consequences
DSM IV (2000) refers to substance-related disorders (2):
The 2 categories
- Substance abuse: Less severe, may or may not lead to substance dependence (not yet there)
- Substance dependence: More severe, akin to addiction
Substance use disorder (2)
What + the scale of symptoms
- A pattern of maladaptive substance use over at least a 12-month period, that had led to significant impairment or distress.
- 2-3, 3-5, 6+ # of have the symptoms mild-moderate-severe
Positive reinforcement model
Self-adminstration studies: Fixed-ratio (FR) schedule (5)
What + curve + ascending + descending + high []
- Ratio schedules involve reinforcement after a certain number of responses have been emitted. The fixed ratio schedule involves using a constant number of responses. For example, if the rabbit is reinforced every time it pulls the lever exactly five times, it would be reinforced on an FR 5 schedule
- The typical dose-response functions is an inverted U-shaped curve
- Ascending curve = increased reinforcing effectiveness of drug (animal is working for it)
- Descending curve = satiation to drug, aversive reactions, side effects (hyperactivity, sedation)
- At high concentration, cocaine is more reinforcing than heroin.
** EDIT/UPDATE SLIDE*
A progressive ratio (PR) schedule of reinforcement (4)
what + example + increased until + BP?
- an increasing response requirement for reinforcer delivery over successive sessions
- Lever press on a continous reinforcement schedule (1 to 1) to a low fixed ratio scheduled (ex: FR-5)
- FR schedule is increased progressively until the animal stops responding
- Higher breaking point for higher morphine dose
Explain the process of extinction and reinstatement in positive reinforcement FR studies (4):
- Rats are hooked onto a machine, self-adminstration schedule FR of cocaine, they are initially trained.
- 14 days to extinguish response. Press lever no drugs and response is distinguished
- End of 2 week, rapid fall of responding. Then either exposed to stress, environmental cues or drug priming.
- High rate of response (relapse)
The graph depicts typical data from rats that were first stabilized on IV drug (e.g., cocaine) self-administration using an FR schedule of reinforcement. The red data points show the number of responses per session on a lever that is linked to drug delivery. Each drug infusion is accompanied by presentation of a cue, which is typically a light or a tone. The purple data points show the number of responses per session on a control lever that has no consequences when pressed. After 12 days of self-administration in this particular paradigm, the animals are switched to a 14-day extinction (E) phase in which pressing the drug lever no longer elicits either drug delivery or cue presentation. Note the rapid falloff of responding during this phase. However, if the drug-paired cue is presented, if the animals are subjected to stress (e.g., foot shock), or if a priming dose of the drug is administered by the experimenter, the animals resume a high rate of responding on the drug lever despite the fact that the drug is still withheld (E14). This phenomenon, which is termed reinstatement, is considered to be an animal model of relapse to drug use after abstinence in drug addicts.
The rat park experiment (3)
what + results
- Rats given a choice between standard drinking water or morphine solution
- 2 Groups, isolation and enriched housing
- Results showed that isolated rats consumed significantly more morphine than those that were socially housed. Perhaps consumption of drugs are from environmental factors like discomfort.
Gateway Theory (2)
What + pathway
- Use of a drug at one stage in the sequence serves as a risk factor that predicts an increased likelihood of using drug at the next stage.
- Someone starts legal drugs (alcohol, nicotine) -> progress to marijuana -> heroine/cocaine
Progression wheel towards addiction: (3)
- Periods of preoccupation with drugs and anticipation of upcoming use
- Periods of drug intoxication, in some cases associated with bingeing
- Periods following drug use characterized by withdrawal symptoms and negative effects
Physical dependence model (4)
what + reinforcement + may be bc of
- Attempts at abstinence following chronic drug use results in withdrawal symptoms/ abstinence syndrome
- Relief of withdrawal symptoms promotes drug-taking behaviour (relapse)
- Negative reinforcement
- May be because of changes in the brain
Biopsychosocial model
- A balance between factors that promote drug addiction and those that are protective
- A consideration of multiple factors is necessary to understand addiction: behaviour, pharmacology, biology, psychology
How do we know DA is important experiment?
- Teach aminal to cell administrate (bar press for cocaine/heroin)
- Lesion dopamine neuron (Kainic acid lesion of nucleus accumbens, distript DA release)
- See what happens to self-adminstration
Results: Damages to the nucleus accumbens is negatively correlated with cocaine intake. Intake is less if they is more damage. Animal is not getting as much rewarding effect and this not self-adminstrating.
