Term
| What are the two primary types of synapses? |
|
Definition
|
|
Term
| Gap junctions, connexions, electrotonic synapses, and ephaptic connections are all examples of what? |
|
Definition
|
|
Term
| Within the CNS, electrical synapses are most common among what types of cells? |
|
Definition
| Glial cells (though also occurs between neurons) |
|
|
Term
| Specializations of cell membranes, most commonly epithelia, where ion channels allow the exchange of ions between cells are characteristic of what type of chemical synapse? |
|
Definition
|
|
Term
| Ephaptic connections are most common among what types of cells in the CNS? |
|
Definition
|
|
Term
| What type of electrical synapse uses connexons to form channels between two nearby cell membranes? |
|
Definition
|
|
Term
| Gap junctions allow the transfer of what kinds of substances between synaptic cells? |
|
Definition
|
|
Term
| Gap junctions are used in the nervous sytem to allow for a very rapid transmission of information between neurons responsible for what types of actions? |
|
Definition
| Oscillatory or rhythmic (ex. olfactory bulb, hypothalamus, eye movement nuclei) |
|
|
Term
| What disease is characterized by defects in genes for connexins that results in demyelination and slowing of conduction in peripheral axons, leading to muscle weakness, atrophy, and sensory loss? |
|
Definition
| Charcot-Marie-Tooth disease |
|
|
Term
| The use of chemical substances known as neurotransmitters in order to convey electrical activity between neurons describes what type of synapses? |
|
Definition
|
|
Term
| Which are faster, chemical or electrical synapses? Which allows for more complex information processing? |
|
Definition
| Electrical synapses are slower, allow for more complex signals |
|
|
Term
| What are the three primary elements of chemical synapses? |
|
Definition
| Presynaptic element (bouton), synaptic cleft, postsynaptic element |
|
|
Term
| Electrical to chemical transduction in the presynaptic terminal is achieved via depolarization causing the opening of voltage sensitive channels for what ion? |
|
Definition
|
|
Term
| The release of neurotransmitter into the synaptic cleft is controlled through what proteins? |
|
Definition
| Calmodulin and synaptotagmin |
|
|
Term
| Neurotransmitter vesicle membranes are recycled through a process involving what proteins? |
|
Definition
|
|
Term
| What type of axons release neurotransmitters along varicosities rather than at the synaptic junction or via vesicular release? |
|
Definition
| Autonomic axons, usually sympathetic |
|
|
Term
| Where are large molecule neurotransmitters synthesized? |
|
Definition
|
|
Term
| What types of neurotransmitters are commonly recycled? |
|
Definition
|
|
Term
| What are the two synapse receptor categories? |
|
Definition
|
|
Term
| What type of synapse include small molecule synapses, fast synapses, and single messenger synapses? |
|
Definition
|
|
Term
| What type of synapses include larger neuropeptide synapses, slow synapses, and second messenger synapses? |
|
Definition
|
|
Term
| Activation of ionotropic receptors at postsynaptic axons generally leads to what response? |
|
Definition
| Depolarization or hyperpolarization of the postsynaptic membrane |
|
|
Term
| Metabotropic synapses generally cause what type of response in the postsynaptic cell? |
|
Definition
| Activation of an enzymatic cascade to produce a product that produces that actual transduction event |
|
|
Term
| What is tthe main advantage to metabotropic synapses? |
|
Definition
| Magnification of transduction and regulation of the postsynaptic cell |
|
|
Term
| The majority of metabotropic receptors initate what type of protein mediated pathway? |
|
Definition
| G-protein mediated second messengers |
|
|
Term
| What are the most common secondary messengers? |
|
Definition
| Adenylyl cyclase, phospholipase C, phospholipase A |
|
|
Term
| Adenylyl cyclase produces what second messenger for protein phosphorylation? |
|
Definition
|
|
Term
| Phospholipase C produces what secondary messengers in order to release calcium stores? |
|
Definition
| Phosphoinositol and diacylglycerol |
|
|
Term
| What cascade does phospholipase A initiate? |
|
Definition
|
|
Term
| Describe the steps of the cAMP system |
|
Definition
| Activated receptor -> releases G-protein -> binds to GTP and adenylate cyclase -> converts ATP to cAMP -> stimulates protein kinase A to initiate a response (ex. phsophorylation and opening of sodium ion channels) |
|
|
Term
| The G-protein activated GTP complex in a phospholipase C pathway activates phospholipase C which splits a membrane phospholipid into what two secondary messengers? |
|
Definition
| Diacylglycerol (DAG) and inositol phosphate |
|
|
Term
| Diacylglycerol (DAG) activates what protein in the phospholipase C pathway? |
|
Definition
|
|
Term
| Destruction of the neurotransmitter or modification by membrane bound enzymes at the synaptic cleft describes what mechanism of removal of neurotransmitters at the synpatic cleft? |
|
Definition
|
|
Term
| Pinocytosis or direct uptake of neurotransmitters bound to recepors on the postsynaptic cleft describes what mode of neurotrasmitter removal? |
|
Definition
|
|
Term
| Describe the reuptake process of catecholamines |
|
Definition
| Inactivated by MAO and COMT, taken up at presynaptic terminal for reuse or diffusion |
|
|
Term
| Astrocytes are particularly active in the regulation and control of what substances? |
|
Definition
|
|
Term
| Neurotransmitter receptors on neuroglial cells modulate neuroglial control of what tasks? |
|
Definition
| Maintenance of synaptic environment, recycling of transmitters, balance of ions in the extracellular environment |
|
|
Term
| What are the other forms of synaptic communication aside from presynaptic to postsynaptic activation? |
|
Definition
| Presynaptic receptor-mediated autoregulation, retrorograde transmission |
|
|
Term
| The process of feedback from the postsynaptic cell is known as what? |
|
Definition
|
|
Term
| In retrograde trnasmission, the postsynaptic cell responds to synaptic activation by releasing a second chemical messenger that affects the presynaptic cell. Give an example of a retrograde neuromodulator |
|
Definition
|
|
Term
| The use of receptors on the presynaptic membrane that bind to the neurotransmitters released at the presynaptic cleft describes what form of regulation? |
|
Definition
| Presynaptic autoregulation |
|
|
Term
| What part of the heart uses presynaptic autoregulation? |
|
Definition
| Sinoatrial node (negative feedback) |
|
|
Term
| Why is retrograde transport important to the neuron? |
|
Definition
| Neuromodulation via retrograde transport is an essential part of cell maintenance. Both the neuron and its target cell may die if this connection is severed. |
|
|
Term
| Phosphorylation of neurotransmitter-bound receptors initiating a reduction in their binding or transduction efficiency describes what type of receptor regulation? |
|
Definition
|
|
Term
| Invaginations internalizing receptors for desensitization are called what? |
|
Definition
|
|
Term
| A decrease in receptor number by means of degredation or regulation of transcription is referred to as what? |
|
Definition
| Downregulation (converse is known as upregulation) |
|
|
Term
| The loss of neuronal contact with a cell may result in a larger than normal increase of receptors via upregulation. This is known as what? |
|
Definition
| Denervation supersensitivity |
|
|
Term
| What are the amino acid neurotransmitters? |
|
Definition
|
|
Term
| What are the biogenic amine neurotransmitters? |
|
Definition
| Acetylcholine, monoamine, catecholamines, serotonin, histamine |
|
|
Term
| What are the neuropeptide neurotransmitters? |
|
Definition
| VIP, substance P, enkephalins, endorphins, orexin, oxytocin, vasopressin |
|
|
Term
| What are the purine neurotransmitters? |
|
Definition
|
|
Term
| What are the gaseous neurotransmitters? |
|
Definition
| Nitric oxide, carbon monoxide |
|
|
Term
| What ist he most prevvalent excitatory neurotransmitter in ths CNS? |
|
Definition
|
|
Term
| How is glutamate synthesized for use in the CNS? |
|
Definition
| From alpha-ketoglutarate by GABA transaminase |
|
|
Term
| What glial cell aides in the recycling of glutamate? |
|
Definition
|
|
Term
| What is the primary inhibitory neurotransmitter in the brain? |
|
Definition
|
|
Term
| In what part of the brain is GABA found in high amounts? |
|
Definition
| Striatum and lentiform nuclei, hypothalamus, hippocampus, periaqueductal gray, purkinje cells of the cerebellum |
|
|
Term
| What is the primary inhibitory neurotransmitter in the brainstem and spinal cord? |
|
Definition
|
|
Term
| What neurotransmitter is important in both the CNS and PNS with both excitatory and inhibitory properties through both inotropic and metabotropic receptors? |
|
Definition
|
|
Term
| What type of neurotransmittters are synthesized from tyrosine to create the neurotransmitters dopamine, norepinepherine, and epinepherine to produce both excitatory and inhibitory effects? |
|
Definition
|
|
Term
| What is the major enzyme involved in the inactivation and recycling of catecholamines? |
|
Definition
| Catechol-O-methyl transferase (COMT) |
|
|
Term
| What biogenic amine neurotransmitters is synthesized from tryptophan to elicit both excitatory and inhibitory effects, particularly dealing with emotional behavioral states? |
|
Definition
|
|
Term
| What excitatory biogenic amine neurotransmitor is synthesized by histidine decarboxylase? |
|
Definition
|
|
Term
| Neuropeptide neurotransmitters use what types of receptors? |
|
Definition
| Metabotropic and G-protein coupled |
|
|
