Psykofarmakologi

Question 1

Hur definieras ‘psykoaktiva substanser’?

Answer 1

Drug = chemical compound administered to bring about some desired change in the body. Psychoactive drug = Drug used to alter mood, thought or behavior

Från föreläsning:
A drug or other substance that affects how the brain works and causes changes in
mood, awareness, thoughts, feelings, or behavior.

Question 2

Group 1: antianxiety agents and sedative hypnotics

Answer 2

Behavioral continuum(with increasing doses): Relief from anxiety > disinhibition > Sedation > Sleep > General anesthesia > Coma > Death
- can impair memory for recent events
- GABAA receptorn ofta en target

Benzo:
Indications: anxiety disorders, insomnia, acute status epilepticus, induction of amnesia, spastic disorders, seizure disorders, agitation
Side effects: drowsiness, light-headedness, confusion, unsteadiness, dizziness, slurred speech, muscle weakness, memory problems, constipation, nausea, dry mouth, blurred vision

Sedative hypnotics (Barbiturates, alcohol)
Indications: insomnia, anxiety, pre-procedure sedation, medically induced coma, other
Side effects: headache, nausea, short-term forgetfulness, rebound insomnia, dry mouth, hallucinations, dizziness, drowsiness, withdrawal symptoms, unpleasant taste, confusion,
dependence.
* induce tolerance
* Cross-tolerance with antianxiety(bc same target - GABAA)

Question 3

Group 5: psychotropics(tror ej ja behöver kunna detta så ingående som jag skrivit i svaret)

Answer 3

Psychotropic drugs are stimulants that mainly affect mental activity, motor activity, arousal, perception and mood.

Behavioral stimulants

• Both cocaine and amphetamine are dopamine agonists that act by blocking the dopamine reuptake transporter.
• Amphetamine also stimulates dopamine release from presynaptic membranes.
• Reinforcing and reward effects: enhanced dopaminergic activity in the mesolimbic pathway.
• Euphoric and locomotor-stimulating effects: increased synaptic dopamine and norepinephrine concentrations in the striatum.
  Acute effects - Increased motor activity, Elevates mood and alertness(concentration, attention), euphoria, increased energy
  CHRONIC EFFECTS: Paranoia, psychotic symptoms, Cognitive deficits, Impulse disorder, Compulsive drug- seeking behavior, Violent behavior Convulsions, Heart diseases, Sudden death due to infarction.

Psychedelic and hallucinogenic stimulants:
Anandamine psychedelic - THC
* THC and CBD bind the CB1 and CB2 receptors in brain and body.
Effects appetite regulation, Motor planning, Reward, Pain, Vomiting reflex, Higher cognitive
functions and sensory perception, Learning, Motor control
ACUTE EFFECTS: Euphoria or relax, Dry mouth, Trouble concentrating, Disturbed memory, Disturbed impulse control.
CHRONIC EFFECTS: Sadness, Apathy, Loss of motivation, Risk for psychopatology, Loss
of interest in daily activities, own appearance, self-care.

Serotonin psychedelics: lysergic acid diethylamide(LSD), psilocybin, MDMA
MDMA - increases reuptake and release of serotonin and norepinephrine
LSD - binds to serotonin and dopamine receptors. Main psychedelic effect through 5-HT2A receptor activation
Psilocybin - metabolized to psilocin, serotonin 5-HT2A agonist

Annat:
ACh psychedelics: atropine, nicotine, General stimulants: Caffeine

Question 4

Redogör för vilka mekanismer som påverkar psykoaktiva substanser i hjärnan, och var denna kan ses?

Answer 4

1. Synthesis: induce/decrease synthesis
2. Storage: easier/harder for neurotransmitter to be stored
3. Release: facilitate/make release harder(=increasing/decreasing release)
4. Receptor interaction: mimic the effect of the neurotransmitter(agonist)/impede the binding of the neurotransmitter (antagonist
5. Deactivation: speed up/block deactivation
6. Reuptake: facilitate/block reauptake
7. Degradation

Question 5

Tolerance & sensitization (simpel sammanfattning!)

Answer 5

Sensitization
Increased responsiveness to equal doses of a drug
- much more likely to develop with occasional use
Tolerance
-Generally develops with constantly repeated use of a given drug

Question 6

3 types of tolerance

Answer 6

1. Innate tolerance: genetically determined insensitivity
2. Metabolic tolerance/pharmacokinetic tolerance:
   * Develops from an increase in enzymes needed to break down the substance.
   * as a result, the body metabolizes the substance more quickly, so blood-substance levels are reduced
3. Cellular tolerance/pharmacodynamic tolerance:
   * Develops as neurons adjust their activities to minimize the effects of the substance in the blood e.g.. changes in receptor density). * helps to explain why behavioral signs of intoxication may be very low, despite a relatively high blood-substance level
4. Learned tolerance: * People may show reduced signs of intoxication as they learn to cope with the daily demands of living while under the influence