Module 2 Part 3 Vocab

Acetylcholine (ACh)

The primary neurotransmitter of the cholinergic system, involved in muscle contraction, learning, memory, and autonomic functions.

Action Potential

A brief electrical impulse that travels down an axon, forming the basis of nerve communication.

Adenylate Cyclase

An enzyme involved in the synthesis of cAMP, often regulated by G-protein coupled receptors.

Agonist

A drug or chemical that binds to and activates a specific receptor, mimicking the effect of a natural neurotransmitter.

AMPA Receptor

An ionotropic glutamate receptor, playing a large role in learning and memory.

Anandamide

An endogenous cannabinoid, a lipid neurotransmitter involved in anxiolysis, feeding, learning, and memory.

Anterior Pituitary (Adenohypophysis)

The front lobe of the pituitary gland, indirectly controlled by the hypothalamus, which releases tropic hormones into the blood.

Astrocytes

Glial cells in the CNS that play various roles, including the uptake and metabolism of neurotransmitters like glutamate.

Autonomic Nervous System (ANS)

The part of the PNS that regulates involuntary bodily functions, divided into sympathetic and parasympathetic divisions.

Basal Forebrain Cholinergic System

A group of cholinergic neurons at the base of the brain involved in learning, memory, and attention.

Catecholamines

A subclass of monoamine neurotransmitters including dopamine, norepinephrine, and epinephrine, characterized by a catechol ring.

Choline Acetyltransferase (ChAT)

The enzyme responsible for synthesizing acetylcholine from choline and acetyl CoA.

Cholinergic System

The neural system that uses acetylcholine as its primary neurotransmitter.

D1 Family Receptors

Dopamine receptors (D1, D5) that increase intracellular cAMP levels, potentially leading to excitation or inhibition.

D2 Family Receptors

Dopamine receptors (D2, D3, D4) that decrease intracellular cAMP by inhibiting adenylate cyclase, typically resulting in inhibition.

Dopamine (DA)

A catecholamine neurotransmitter involved in motor control, reward, motivation, and executive functions.

DOPA Decarboxylase

The enzyme that converts DOPA into dopamine.

Dopamine β Hydroxylase

The enzyme that converts dopamine into norepinephrine.

Endocannabinoids

Lipid neurotransmitters synthesized on demand, involved in anxiolysis, feeding, learning, and memory.

Endorphins

Opioid neuropeptides that act as natural pain killers.

Enkephalins

Opioid neuropeptides, similar to endorphins, involved in pain modulation.

Excitatory Amino Acids

Amino acid neurotransmitters (e.g., glutamate) that depolarize neurons, increasing the likelihood of an action potential.

Excitotoxicity

Neuronal death caused by excessive stimulation, often due to high levels of excitatory neurotransmitters like glutamate.

GABA (Gamma-aminobutyric acid)

The main inhibitory amino acid neurotransmitter in the CNS.

GABA A Receptor

An ionotropic, ligand-gated Cl⁻ channel that mediates fast inhibitory responses in the GABAergic system.

GABA B Receptor

A metabotropic receptor that mediates slow inhibitory responses by inhibiting Ca²⁺ and activating K⁺ channels.

GABA C Receptor

An ionotropic Cl⁻ channel, similar to GABA A, primarily found in the retina.

GABAergic System

The neural system that uses GABA as its primary neurotransmitter.

Gaseous Neurotransmitters

Nonclassical transmitters like nitric oxide, carbon monoxide, and hydrogen sulfide, synthesized on demand, involved in synaptic plasticity.

Glutamate

The most widely used excitatory amino acid and neurotransmitter in the CNS, crucial for learning, memory, and neuroplasticity.

Glutamic Acid Decarboxylase (GAD)

The enzyme that synthesizes GABA from glutamate.

Glutamine Synthetase

An enzyme primarily in astrocytes that breaks down glutamate into glutamine for recycling.

G-Protein Coupled Receptors (Metabotropic)

Receptors that, when activated, trigger intracellular cascades via G-proteins and second messengers, leading to slower, prolonged effects.

Hormones

Peptides or other molecules released by endocrine or neuroendocrine cells into the bloodstream to act on distant targets.

Indolamines

A subclass of monoamine neurotransmitters, primarily serotonin.

Inhibitory Amino Acids

Amino acid neurotransmitters (e.g., GABA) that hyperpolarize neurons, decreasing the likelihood of an action potential.

Ionotropic Receptors

Receptors that form an ion channel themselves, allowing fast effects when activated.

KA (Kainate) Receptor

An ionotropic glutamate receptor.

Lateral Tegmental Area

A cluster of noradrenergic neurons in the midbrain involved in motor coordination and feeding behaviors.

Lipid Transmitters

Nonclassical neurotransmitters synthesized from lipids, such as endocannabinoids.

Long-Term Potentiation (LTP)

A persistent strengthening of synapses based on recent activity patterns; a cellular model for learning/memory, often involving NMDA receptors.

Locus Coeruleus

A major cluster of noradrenergic neurons in the pons, projecting widely and involved in arousal, attention, memory, and mood.

Mesocortical Pathway

A dopaminergic pathway from the VTA to cortical areas (especially frontal), involved in focus, concentration, and executive functions.

Mesolimbic Pathway

A dopaminergic pathway from the VTA to limbic structures, crucial for reward, motivation, and pleasure.

Mesostriatal (Nigrostriatal) Pathway

A dopaminergic pathway from the substantia nigra to the striatum, vital for motor control.

Monoaminergic Systems

Neural systems that use monoamine neurotransmitters (dopamine, norepinephrine, epinephrine, serotonin).

Monoamines

A class of neurotransmitters (biogenic amines) divided into catecholamines and indolamines.

Muscarinic Receptors

G-protein coupled acetylcholine receptors, found in the brain and parasympathetic division, mediating slower responses.

Neuropeptides

Short chains of amino acids that act as neurotransmitters; slow-acting modulators synthesized in the cell body.

Neuroendocrine System

Communication between brain and body using hormones, involving the hypothalamus and pituitary.

Neuromodulation

A process by which signaling molecules alter neuronal excitability or synaptic strength, often in a prolonged/diffuse manner.

Neurotransmitters

Chemical messengers released by neurons that transmit signals across synapses.

Nicotinic Receptors

Ionotropic acetylcholine receptors at neuromuscular junctions, in the brain, and in both autonomic divisions; mediate fast EPSPs.

Nitric Oxide (NO)

A gaseous neurotransmitter/neuromodulator involved in synaptic plasticity and interactions between other transmitters.

NMDA Receptor

A voltage-dependent ionotropic glutamate receptor critical for learning and memory, particularly in LTP.

Noradrenergic System

The neural system that uses norepinephrine as its primary neurotransmitter.

Norepinephrine (NE)

A catecholamine neurotransmitter involved in attention, arousal, mood, and sympathetic functions.

Oxytocin

A neuropeptide/hormone released by the posterior pituitary; roles in social bonding, uterine contraction, and memory.

Parasympathetic Nervous System

A division of the ANS using ACh, involved in 'rest and digest.'

Parkinson's Disease (PD)

A neurodegenerative disorder with motor symptoms due to degeneration of dopaminergic neurons in the substantia nigra.

Posterior Pituitary (Neurohypophysis)

The back lobe of the pituitary, directly controlled by the hypothalamus; releases vasopressin and oxytocin.

Preganglionic Neurons

Autonomic neurons with cell bodies in the CNS whose axons project to autonomic ganglia.

Prolactin

A hormone whose release is inhibited by dopamine (tuberoinfundibular pathway); involved in lactation.

Raphe Nucleus

Brainstem nuclei that are the primary source of serotonin in the CNS.

Serotonin (5-HT)

An indolamine neurotransmitter involved in mood, emotional behaviors, sleep, appetite, and learning.

Serotonergic System

The neural system that uses serotonin as its primary neurotransmitter.

Somatic Nervous System

The PNS division controlling voluntary skeletal muscle; uses ACh at the neuromuscular junction.

Substance P

A neuropeptide that relays pain information.

Substantia Nigra (SN)

A midbrain nucleus of dopaminergic neurons projecting to the striatum; crucial for motor control.

Sympathetic Nervous System

A division of the ANS for 'fight or flight,' using NE at postganglionic neurons.

Synaptic Plasticity

The ability of synapses to strengthen or weaken over time with activity; basis for learning/memory.

Tyrosine

The amino acid precursor for dopamine, norepinephrine, and epinephrine.

Tyrosine Hydroxylase

The enzyme converting tyrosine into DOPA, the first step in catecholamine synthesis.

Vagus Nerve (CN X)

A cranial nerve innervating many organs; key in the parasympathetic system (as shown by Loewi).

Vagusstoff

Otto Loewi's name for the vagus-released substance that slowed heart rate—later identified as acetylcholine.

Vasopressin

A posterior pituitary hormone involved in water balance and memory.

Ventral Tegmental Area (VTA)

A midbrain nucleus of dopaminergic neurons projecting to limbic/cortical areas; crucial for reward and motivation.