bio psych chapter 3
purines
a category of chemicals including adenosine
acetylcholine
a chemical similar to an amino acid except that the NH2 group has been replaced by an N(CH3)3 group
hormone
a chemical that is secreted into the blood stream
excitatory postsynaptic potential (EPSP)
a graded depolarization in the postsynaptic potential
inhibitory postsynaptic potential (IPSP)
a temporary hyper polarization in the postsynaptic cell
amino acids
acids containing an amine group
G-protein
activated when a metabotropic receptor is activated this then causes and increase in secondary messengers
6 major categories of neurotransmitters
amino acids, neuropeptides, acetylcholine, monoamines, purines, gases
achetylcholinesterase
an enzyme that breaks down acetylcholine
COMT
an enzyme that breaks down excess dopamine
monoamine oxidase (MAO)
breaks down transmitters like seratonin, dopamine, or neuroepinephrine into inactive chemicals
neuropeptides
chains of amino acids
ligand-gated channels
channels where a ligand binds directly to the channel
catecholamines
epinephrine, norepinephrine, and dopamine
anterior pituitary gland
hypothalamus secretes releasing hormones which flow through the blood to the
metabotropic effects
initiation of a series of reactions that are slower and longer lasting than ionotropic effects
posterior pituitary gland
neurons in hypothalamus synthesize hormones oxytocin and vasopressin which migrate down axons to here
monoamines
neurotransmitters containing one amine group
gases
nitric oxide and others
exocytosis
release of neurotransmitter from presynaptic neuron
temporal summation
repeated stimuli within a brief time have a cumulative effect
spatial summation
synaptic inputs from separate locations combine their effects on a neuron
reflex arc
the circuit from sensory neuron to muscle response is called a reflex arc
vesicle
tiny nearly spherical packets where neurotransmitters are stored
ionotropic effects
when a channel opens for a certain type of ion