Neurotransmitters and Drugs

Vocabulary flashcards based on lecture notes about neurotransmitters and their actions.

Depolarization

Occurs when an excitatory NT opens Na+ or Ca++ channels, allowing positive ions to enter the cell, depolarizing the membrane.

Hyperpolarization

Occurs when an inhibitory NT opens K+ or Cl- channels, allowing positive ions (K+) to exit or negative ions (Cl-) to enter the cell, hyperpolarizing the membrane.

Neurotransmitters

Chemical messengers between neurons that have different chemical structures, can be excitatory or inhibitory, and act fast (directly) or more slowly (indirectly).

Direct Neurotransmitter Action

Neurotransmitters bind directly on the receptor which opens an ion channel

Indirect Neurotransmitter Action

Neurotransmitters bind to a receptor, triggering a series of chemical events inside the cell that lead to changes in membrane permeability, gene activation, or enzyme activation.

Acetylcholine (ACh)

A neurotransmitter that binds to skeletal, smooth, and cardiac muscle, acting differently at each location and can be excitatory or inhibitory, direct or indirect.

Acetylcholine (ACh) Action on Skeletal Muscle

A neurotransmitter; when binding to skeletal muscle and brain cells, it is excitatory and fast-acting by opening chemical gated Na+ channels.

Acetylcholine (ACh) Action on Heart Muscle

A neurotransmitter; when binding to heart muscle, it is inhibitory and slow-acting by opening K+ channels indirectly.

Acetylcholine (ACh) Action on Smooth Muscle

A neurotransmitter; when binding to smooth muscle, it is excitatory and slow-acting because it opens Ca++ channels indirectly.

Norepinephrine

A neurotransmitter that can be excitatory or inhibitory and helps you overcome emergencies

Dopamine

An excitatory neurotransmitter that causes a positive mood.

Serotonin

An inhibitory neurotransmitter that keeps mood calm and level.

Glutamate

An excitatory neurotransmitter that increases neuron activity in the brain, keeping you awake.

GABA (gamma-amino-butyric acid)

An inhibitory neurotransmitter that calms neuron activity in the brain, making you relaxed and sleepy.

Substance P

An excitatory peptide neurotransmitter that transmits pain information to the brain.

Endorphins

Inhibitory peptide neurotransmitters that help turn off pain feelings.

Agonists

Drugs that enhance or help the action of a neurotransmitter.

Antagonists

Drugs that block or stop the action of a neurotransmitter.

Anti-depressant drugs

Drugs that are dopamine agonists that increase the amount of dopamine available in the synapse

Wellbutrin (SDRI)

An anti-depressant that stops dopamine removal, allowing dopamine to stay in the synapse and elevate your mood.

Prozac (SSRI)

A seratonin agonist that blocks removal of Seratonin so it can stay in the synapse to decrease anxiety

Morphine

A drug that acts as an endorphin agonist, helping endorphins reduce pain

Botox

ACh antagonist that prevents ACh from working, relaxing facial muscles to reduce frown lines.

Local anesthetics (Lidocaine)

Block voltage-gated Na+ ion channels in axon, so that the action potential cannot occur, blocking pain

General anesthetics

Inhibit (turn off) excitatory (glutamate) receptors and excite (turn on) inhibitory (GABA) receptors in the brain