Week 3 Flashcards
1
Q
corticospinal tract
A
mostly involved in voluntary muscle control - Considered a descending motor pathway
2
Q
Decussation
A
the crossing of the fibers of the corticospinal tracts from one side of the central nervous system to the other side.
3
Q
Lateral corticospinal tract
A
distal muscles Anterior corticospinal tract – cervical and upper thoracic.
4
Q
85-90% of nerves cross where?
A
Pyramids of the Medulla
5
Q
There are NO synapses within these descending pathways. So they are called what?
A
upper motor neurons
6
Q
What pathway contains synapses?
A
lower motor neurons
7
Q
pharmacology vs. psycho-pharm
A
psychopharmacology focuses on psychiatric meds specifically
8
Q
Sites of action
A
what reception is the drug binding to?
9
Q
Drug effect
A
observed changes
10
Q
endogenous
A
any substances that your body produces yourself
11
Q
Exogenous
A
any substance that is produced outside of your body.
12
Q
Pharmacokinetics
A
What the body does to the drug, ex:
* Absorption
* Distribution
* Metabolism
* Excretion
13
Q
Rate of Absorption & Distribution
A
*5L/min blood pumped every minute
* Entirevolumeofbloodsupply circulates every minute
14
Q
what is the fastest and most dangerous administration:
A
intravenous: 30-60 seconds
15
Q
Different administration types:
A
- Intravenous
- Intraperitoneal
- Intramuscular
- Subcutaneous (under the skin)
- Intracerebral (bypass BBB)
- Intracerebroventricular
- Oral
- Intrarectal
- Inhalation (lungs) vs. insufflation (nasal passages)
- Topical (skin)
16
Q
Intraperitoneal
A
into your stomach
17
Q
Intramuscular
A
into the muscle
18
Q
Subcutaneous
A
into the fat
19
Q
Intracerebral
A
into the brain - lets your bypass the BBB
20
Q
Intrarectal
A
in the butt :) - bypasses metabolism
21
Q
Most common administration
A
oral - not a very fast route of admin because it is metabolized
22
Q
Inhalation vs. insufflation
A
lungs vs. nasal
23
Q
topical
A
through the skin
24
Q
Distribution
A
Entry of Drugs into the Brain
25
when do drugs have any impact?
once they reach the site of action
26
lipid solubility
it can bypass the BBB
27
what is the primary organ for excretion?
kidneys
28
what organ has an active role in enzymatic deactivation?
liver
29
Many drugs are metabolized and deactivated by what?
enzymes
30
what can transform a substance into having a more effective/active molecule?
enzymes
31
Dose-response curve
point of maximum effect
32
Drug effectiveness is Impacted by (2):
* Sites of Action
* Affinity of a drug for its site of action
33
Affinity
the capacity of a drug molecule to bind to a key site of action
34
Affinity
the capacity of a drug molecule to bind to a key site of action
35
Margin of Safety (MoS)
The difference between the usual effective dose and the dose that causes severe or life-threatening side effects
36
Effective Dose 50 (ED50)
the dose that produces the desired effects in 50 percent of the individuals
37
Toxic Dose 50 (TD50)
the dose that produces toxic effects in 50 percent of the individuals
38
ED50 and TD50 provide a ratio for what?
Therapeutic Index
39
Therapeutic Index
a quantitative
measurement of the relative safety of a drug.
40
and ideal therapeutic index =
greater than 10
41
Drugs with low TI (5)
* Lithium
* Carbamazepine
* Valproic Acid
* Clozapine
* Tricyclic Antidepressants
(typically antipsychotics)
42
Neurotransmitter
a chemical used for neuron-to-neuron communication.
43
Neuromodulator
a chemical that affects the neurotransmission of a whole group of neurons.
44
Agonist
(increasing) a molecule that by binding to the receptor stimulates a response
45
Antagonists
(decreasing) a molecule that by binding to a receptor blocks or inhibits the response
46
Neurotransmitters produced at the pre-synaptic neuron with the aid of what?
enzymes and precursors
47
A drug that blocks the re-uptake or enzymatic degradation of a neurotransmitter?
Agonist - because it is increasing the number of neurotransmitters in the Synaptic cleft
47
A drug that blocks the re-uptake or enzymatic degradation of a neurotransmitter?
Agonist - because it is increasing the number of neurotransmitters in the Synaptic cleft
48
Direct agonists (2)
- mimics neurotransmitters
- Binds with and activates the receptor
49
Direct antagonists/Receptor Blockers (2)
- Bind and block the receptor from being activated.
- Sits on receptor and prevents ion channels from opening
50
Indirect agonist (2)
* Attach to alternate binding site
* Facilitates/stimulates receptors actions
51
Indirect antagonist (2)
* Attach to alternate binding site
* Blocks/reduces the receptor actions
52
Amino acid neurotransmitters in the brain:
* Excitatory - Glutamate
* Inhibitory - Gamma-aminobutyric acid (GABA)
53
Amino acid in the spinal cord and lower brain stem:
* Excitatory - Glutamate
* Inhibitory – Glycine
54
What is the "go" NT?
Glutamate
55
NMDA receptor has how many binding sites?
6 total. 4 on the exterior and 2 on the interior
56
Requirements for Glutamate to bind: (2)
* Glycine must be attached
* Mg must not be attached -must be depolarized to bind
57
Alteration of the synapse (synaptic plasticity) =
building block of a newly formed memory
58
Ketamine & PCP cause what?
indirect antagonists to NMDA receptor = hypofunction. reduces ability to learn and create new memories
59
When you have too much glutamate stimulation =
glutamate excitotoxicity - damaged neurons (noted in ALS).
60
What is the "stop" NT
GABA
61
GABA receptors
* 5 binding sites
* Indirect agonists that bind to GABAa = benzos, some sleep meds, barbiturates, steroid hormones = sedating effects
* Indirect antagonists at high doses = seizures
62
Acetylcholine (ACh) functions in which 2 systems?
Functions in both CNS and PNS
63
Acetylcholine in the PNS
central role in muscle contraction
64
Acetylcholine in the CNS
Found in specific locations and pathways in CNS. Key role in REM sleep, perceptual learning, and memory.
65
Nicotinic Receptors
faster; CNS & neuromuscular junctions
66
Muscarinic Receptors
slower; CNS and PNS to innervate visceral organs
67
Monoamines
Neuromodulators derived from a single amino acid.
68
What system produces monoamines?
several systems in the brain
69
What are the three catecholamines?
(know for the test)
dopamine, Norepinephrine/noradrenalin, and Epinephrine/adrenalin
70
how many dopamine receptors are known?
5
71
Re-uptake is completed by what?
transporters (i.e., dopamine transporter)
72
Norepinephrine Primary effect is what?
vigilance/attentiveness
73
what is converted to norepinephrine by a special enzyme?
Dopamine in vesicles
74
Locus Coeruleus
(know for test)
Where most noradrenergic systems begin
75
Serotonin (5HTP)
Involved in mood and pain regulation, and the control of eating, sleep, arousal, and dreaming.
76
Precursor to 5HTP
Tryptophan
77
Tolerance
A decrease in the effectiveness of a drug that is administered repeatedly.
78
Pharmacokinetic tolerance
body breaks down drug preventing it from reaching
receptors
79
Pharmacodynamics tolerance (3)
* Decrease in receptor affinity for drug.
* Damaged receptors
* Decrease in receptor availability aka Receptor Downregulation
80
Sensitization
An increase in the effectiveness of a drug as it is administered repeatedly.
81
Dependence
the physical or psychological symptoms that occur that make someone feel like they must continue taking a substance.
82
Addiction
The inability to stop, control the use of substance(s), seek out the substance despite experiencing negative consequences (a behavior).
83
Placebo
an inactive/inert substance given as a control in substance experiments.
84
Viewing injection of placebo causes what?
decreased post-operative pain (Price et.al, 2008)
85
Telling participants that a placebo is a stimulant causes what?
increased heart rate and blood pressure
86
effects of drugs on the basil ganglia
motivation, habits, routines
87
effects of drug on the amygdala
anxiety, irritability, and unease
