BBH 143 Exam 2

Cell body

Dendrite

Axon

Glia

Support cells (glue) of the nervous system

Neurons

Cells that allow for rapid signaling throughout the body

Blood-Brain Barrier

Blocks big bundles (only certain small molecules, like those comprising psychoactive drugs, can cross into the brain)

Microscopic structure between blood vessels and the fluid surrounding the brain and spinal cord

Neurotransmission

Communication between neurons (In brain, spinal cord, nerves of the body)

Action Potentials

Electrochemical events that trigger neurotransmission

Synapse

A junction between two neurons where those neurons are communicating

Synaptic Cleft

Space between the presynaptic neuron and postsynaptic neuron

Presynaptic Neuron

Sending the signal

Postsynaptic Neuron

Receiving the signal

Neurotransmitters

Molecules that are performing the signaling

GABA

Glutamate and Acetylcholine

Some hallucinogens block receptors

Serotonin

A factor in hallucinations, mimicked by psychedelic drugs

Monoamines

Dopamine

Serotonin

Norepinephrine

Dopamine

At the heart of the brain’s reward system

Reuptake

Presynaptic neuron reabsorbing NTs via transporters

Degradation

NTs are chemically metabolized (broken down) by enzymes

Central Nervous System (CNS)

Brain and Spinal Cord

Peripheral Nervous System (PNS)

Nerves and ganglia

Includes autonomic nervous system

Prefrontal Cortex (Frontal lobe)

Higher-order cognitive functions 

Reduced and dysregulated activity in addiction

Brainstem

Involved in many autonomic/homeostatic functions

Cerebellum

Involved in sequencing/coordination of movement, balance

Can be damaged by chronic alcohol use

Mesolimbic Dopamine Pathway

The brain’s major reward system

Dopamine is synthesized in…

ventral tegmental area

Pharmacology

The interaction between drugs and living organisms

Or the biomedical field that studies these interactions

Neuropharmacology

The interaction between drugs and the nervous system

Psychopharmacology

The interaction between drug and cognitive processes

Specific Drug Effects

The effects of a drug depending on its presence at specific concentrations in the target tissue (direct pharmacological effects)

Non-Specific Drug Effects

The effects of a drug relating to anything except its direct pharmacological effects

Set

User’s psychological state, personality, expectations

Setting

Physical and social environments of use

Placebos

Inherit drug that doesn’t do anything

Side Effects

Unintended (usually undesired) secondary drug effects

Drug Interactions

Chemical reactions between drugs affecting physiology and/or psychology

Pharmacokinetics

The factors that affect the movement of a drug into, through, and out of the body

Time Course

The timing of the onset, duration, and termination of a drug’s effect

First-Pass Metabolism

The phenomenon in which the bioavailability of drugs is reduced

Most significant in oral administration via liver metabolism

Bioavailability

Percentage of drug that is administered that enters your bloodstrem

Metabolite

The intermediate or end product(s) of metabolism

Half-Life

The amount of time it takes for a drug’s blood concentration to be reduced by 50%

ADME

Absorption

Distribution

Metabolism

Excretion

Absorption

How does the drug get in?

Distribution

Where does the drug go?

Metabolism

How is the drug broken down?

Excretion

How does the drug leave?

Corelates

General health status

Age

Gender/Sex

Ethnicity

Pharmacodynamics

The factors that affect the relationship between a drug and its target receptors

Agonist

A drug that binds to and activates a neuronal receptor, mimics the action of that receptor’s NT

Antagonist

A drug that binds to and blocks the NT from binding to its receptor

Cross-Tolerance

Tolerance of one drug generalizing to other chemically related drugs

Behavioral tolerance

Tolerance caused by learned behavioral adaptation to a drug

Threshold

The lowest dose of a drug that has an effect

Effective dose (ED)

The amount of drug required to produce a specific response

• The potency of one drug relative to another is measured by comparing EDs relative to the same specific response

• High potency = Lower relative ED

ED₅₀

The effective dose for 50% of the tested population

Lethal dose (LD)

The amount of drug required to result in death

LD₅₀

The lethal dose for 50% of the population

Therapeutic Index (TI)

LD₅₀/ED₅₀

Lower = More lethal 

Cocaine

A psychoactive alkaloid produced by the coca plant 

• Native to South America

Cocaine Hydrochloride (HCI)

Powdered Cocaine

Typically snorting or intravenously injected (dissolved)

Crack Cocaine

Mode of administration: Smoking

Coca Plant

Native to South America

Stimulant

“Upper” 

A drug that generally increases activity in the CNS and/or body

Crack Baby

Children doomed to life of addiction, physical, and psychological suffering, intellectual disability

Fair Sentencing Act of 2010

Reduced crack-to-cocaine HCL sentencing disparity from 100:1 to 18:1

Cocaine Pharmacodynamics

Blocks reuptake by suppressing presynaptic transporters for monoamine neurotransmitters 

Speedballs

A stimulant and depressant (usually opioid) co-administered

Carry higher risk of dependence and overdose than cocaine alone 

Possible Chronic Effects of Cocaine

Insomnia

Cardiomyopathy

Septal Necrosis

Formication

Insomnia

Chronic effect of cocaine

Inability to fall or stay asleep

Cardiomyopathy

Chronic effect of cocaine

Disorder of the muscles in the heart

Septal Necrosis

Chronic effect of cocaine

Damaging the nasal septum overtime due to snorting cocaine 

Formication

Chronic effect of cocaine

Break from reality; Hallucination that there re bugs crawling on your skin

Amphetamine (Proper)

Powder and pills

Benzendrine

Inhaler 

Replacement for ephedrine in treating asthma 

Methamphetamine

Substituted amphetamine

Powder, pills, base, crystal

Crystal Meth

“Ice” 

Most common in the US

Cathinone

“Bath Salts”

Bath Salts

Cathinone

Flakka

Type of bath salt

Ephedrine

Used for ~5000 years in Chinese medicine

Replaced by Benzedrine 

Summer of Love

“Speed Scene” Culminates in 1967

Pharmacodynamics of Amphetamines

Mimic monoamine neurons

Enhanced release of monoamines into synaptic cleft

Enhanced signaling at dopamine, serotonin, and norepinephrine synpases

Meth is more effective than Amphetamine proper

Stroke

Death of tissue in the brain due to extended deprivation of oxygenated blood

Hyperthermia

Abnormal inability to cool oneself down

Meth Mouth

Severe tooth decay/loss

Meth Sores

Open wounds on skin

Caused by formication or injection

Therapeutic Uses of Amphetamines

Depression

Weight loss

Narcolepsy

Narcolepsy

A sleep disorder marked by extreme fatigue during the day and involuntary lapses into sleep

ADHD

Neurodevelopmental disorder variably marked by excessive inattention, hyperactivity, impulsivity, and/or emotional dysregulation

Explain the relationship between the ventral tegmental area, nucleus accumbens, and dopamine in the context of the mesolimbic reward pathway

The mesolimbic reward pathway is the brain’s major reward system. Dopamine is synthesized in the ventral tegmental area, also the brainstem, which signals the nucleus accumbens, also the deep forebrain structure. This activates both during and anticipating pleasurable activities.

Explain why drugs with a lower therapeutic index (TI) are more likely to kill you, using the terms LD₅₀ and ED₅₀

Drugs with a lower TI are more likely to kill you because you calculate TI by dividing LD₅₀ by ED_50. If a drugs LD50 is 10 grams and ED is 5, that means the TI is 2. But a drug that has a LD50 of 20 and a ED of 2, then the TI is only 10. So the lower the TI, the lower the gap between an effective dose and a lethal dose. 

Explain why there has been a rise in reported cocaine-related fatal overdoses since 2015

Cocaine is being laced with potent opioids, like fentanyl. Speedballing

Provide two reasons why amphetamines were preferred as stimulants over cocaine during combat in WWII

Cocaine has a very short half-life

Amphetamines are easier to swallow 

Identify and explain one potential cause of meth sores

Formication; Hallucination that there are bugs crawling all over your skin → Scratching and itching at skin until cuts/wounds form.