exam 1 key terms Flashcards
antidepressants
a drug class that contains medications used to treat major depressive disorder, some anxiety disorders, some chronic pain conditions, and help to manage some addictions. Common side-effects of antidepressants include dry mouth, weight gain, dizziness, headaches, sexual dysfunction, and emotional blunting
anxiolytic
a medication or other intervention that reduces anxiety. This effect is in contrast to anxiogenic agents which increase anxiety. Anxiolytic medications are used for the treatment of anxiety disorders and their related psychological and physical symptoms.
Anxiety, mild behavioral agitation, and insomnia.
bioavailability
the proportion of a drug or other substance which enters the circulation when introduced into the body and so is able to have an active effect.
Key indicator of drug absorption. It represents the administered dose fraction which archives success in reaching the systemic circulation when administered orally or through any other extravascular dosing route.
clearance
is equal to the rate at which a drug is removed from plasma (mg/min) divided by the concentration of that drug in the plasma. The total ability of the body to clear the drug from the plasma is renal clearance plus hepatic clearance plus clearance from all other tissues.
clinical response
also used as an indicator of therapeutic efficacy in combination with other indicators. Represents a complex phenotypes that emerges from the interplay of drug-specific, human body, and environmental factors
convulsants
a drug which induces convulsions and/or epileptic seizures. These drugs generally act as stimulants at low doses.
Substances that act in the brain stem or spinal cord to produce tonic or clonic convulsions, often by removing normal inhibitory tone. They were formerly used to stimulate respiration or as antidotes to barbiturate overdose
distribution
the movement of a drug to and from the blood and various tissues of the body and the relative proportions of drugs in the tissue
Distribution is generally uneven because of differences in blood perfusion, tissue binging (because of lipid content), regional pH, and permeability of cell membranes
The entry rate of a drug into a tissue depends on the rate of blood flow to the tissue, tissue mass, and partition characteristics between blood and tissue.
The extent of drug distribution into tissues depends on the degree of plasma protein and tissue binding. In the bloodstream, drugs are transported partly in solution as free drug and partly reversibly bound to blood components.
efficacy
describes the maximum response that can be achieved with a drug. The effect of the drug is plotted against dose in a graph, to give the dose-response curve. The increasing doses are displayed by the X acis and the half maximal and maximal responses are displayed by the Y axis.
hallucinogens
large and diverse class of psychoactive drugs that can produce altered states of consciousness characterized by altered states of consciousness characterized by major alterations in thought, mood, and perception, among other changes. Most hallucinogens can be categorized as psychedelics, dissociatives, or delirants.
narcotic analgesics
substances that act on opioid receptors to produce morphine-like effects. Medically they are primarily used for pain relief.
Have actions at two sites, the presynaptic nerve terminal and the postsynaptic neuron. The postsynaptic actions of opioids are usually inhibitory. The presynaptic action of opioids is to inhibit neurotransmitter release, and this is considered to be their major effect in the nervous system.
pharmacology
neuropharmacology
psychopharmacology
pharmocokinetics
pharmacodynamcs
physical nature of a receptor
active transport
the movement of ions or molecules across a cell membrane into a region of higher concentration, assisted by enzymes and requiring energy
adverse effects
an unexpected medical problem that happens during treatment with a drug, they may be mild, moderate, or severe. Unintended pharmacologic effects, not the same thing as a side effect.
Ex: rashes, jaundice, anemia, decrease in white blood cell count
agonist
a drug or substance that binds to a receptor inside a cell or on its surface and causes the same action as the substance that normally binds to the receptor
amplification
a judged tendency of a person to amplify physical symptoms based on psychological factors such as anxiety or depression
biotransformation
the process by which substances that enter the body are changed from hydrophobic to hydrophilic molecules to facilitate elimination from the body. This process usually generates products with few or no toxicological effects
competitive antagonist
binds to the same site as the agonist but does not activate it, thus blocks the agonist action
cross tolerance
tolerance or resistance to a drug that develops through continued use of another drug with similar pharmacological action
cytochrome p-450
a group of heme containing enzymes embedded primarily in the lipid bilayer of the endoplasmic reticulum of hepatocytes, it takes part in the metabolism of many drugs, steroids, and carcinogens.
effective dose
the dose or amount of drug that produces a therapeutic response or desired effect in some fraction of the subjects taking it.
Effector - molecules that translate the drug-receptor interaction into a change in cellular activity. A bodily tissue, structure, or organ that becomes active in response to stimulation.
efficacies
the maximum response that can be achieved with a drug. The effect of the drug is plotted against dose in a graph, to give the dose-response curve
endothelial cells
the main type of cell found in the inside lining of blood vessels, lymph vessels, and the heart. Endothelial cells release substances that control vascular relaxation and contraction as well as enzymes that control blood clotting, immune function and platelet adhesion
facilitated diffusion
a form of facilitate transport involving the passive movement of molecules along their concentration gradient, guided by the presence of another molecule usually an integral membrane protein forming a pore or channel, does not directly involve high energy molecules
first-pass effect
a phenomenon in which a drug gets metabolized at a specific location in the body that results in a reduced concentration of the active drug upon reaching its site of action or the systemic circulation, can ensure the appropriate drug route of administration and dosing of the patient
G proteins
specialized proteins with the ability to bind the nucleotides guanosine triphosphate and guanine diphosphate some G proteins such as the signaling protein RAS, are small proteins with a single subunit, used by cells to convert extracellular signals into intracellular responses, including responses to hormones, neurotransmitters, as well as response to vision, olfaction, and taste signals
gated channels
an ion channels in cell membrane that opens or closes in response to a stimulus such as a neurotransmitter or to a change in pressure, voltage or light
Potencies - a measure of drug activity expressed in terms of the amount required to produce an effect of given intensity
prodrugs
medications that turn into an active from once they enter the body. Prodrugs help improve a medications effectiveness. They may also be designed to avoid certain side effects or toxicities
protein binding
- plasma protein binding refers to the degree to which medications attach to proteins within the blood. A drug’s efficacy may be affected by the degree to which it binds. The less bound a drug is, the more efficiently it can transverse or diffuse through cell membranes.
receptor
- a region of tissue, or a molecule in a cell membrane, which responds specifically to a particular neurotransmitter, hormone, antigen, or other substance
receptor desensitization
refers to the decreased responsiveness that occurs with repeated or chronic exposure to agonist and is a general feature of most signaling membrane receptors. Prolonged stimulation of a response induced by a receptor begins to wane.
receptor down regulation
characterized by a decrease in total receptor number in the cell due to endocytosis and subsequent degradation of the receptors caused by long term exposure to agonists. Reduces the cell’s sensitivity to the molecule
receptor up regulation
upregulation (increase in the number) of receptors occurs when the activity of the receptor is lower than usual, (due to long term administration of an antagonist)
sensitization
the enhancement of a directly elicited drug effect, though adaptive, appears to represent facilitation within a system, making the effect easier to elicit on future occasions
seven transmembrane receptor
form the largest superfamily of cell surface receptors. They respond to a wide range of stimulants including light, hormones, neurotransmitters, and odorants
steady state
reached when the quantity of drug eliminated in the unit of time equals the quantity of the drug that reaches the systemic circulation in the unit of time
steady state
reached when the quantity of drug eliminated in the unit of time equals the quantity of the drug that reaches the systemic circulation in the unit of time
supersensitivity
increased sensitivity by a postsynaptic cell because of decreased input by incoming axons
tachyphylaxis
occurs when a medication suddenly provides a lessened response or benefit than it once did.
therapeutic index
a ratio that compares the blood concentration at which a drug causes a therapeutic effect to the amount that causes death or toxicity
A higher therapeutic index is preferable to a lower one: a patient would have to take a much higher dose of such a drug to reach the toxic threshold than the dose taken to elicit the therapeutic effect
tolerance
a persons diminished response to a drug, which occurs when the drug is used repeatedly and the body adapts to the continued presence of the drug.
transduction
signal transduction is the process in which binding of an extracellular messenger to the cell surface receptor is translated into changes in biochemistry, cell biology, and gene transcription that make it possible for the cell to respond to the information that was received
genetic polymorphism
the inheritance of a trait controlled by a single genetic locus with two alleles, in which the least common allele has a low frequency. A difference in dna sequence. Makes drug metabolism vary by individual
habituation
the term used to refer to psychological dependence on a drug. A condition resulting from the repeated consumption of a drug because of overpowering
hyperreactive
abnormally high sensitivity to stimuli
hypersensitivity
include allergic, exaggerated pharmacologic, and pseudoallergic reactions to medications that result from an enhanced immunologic or inflammatory response
hyporeactive
having or showing abnormally low sensitivity to stimuli
idiosyncratic drug
an adverse reaction that does not occur in most patients treated with a drug and does not involve the therapeutic effect of the drug
lethal dose
non-competitve antagonist
potency
the minimum dose that causes an effect, some criteria established for an effect, a threshold has to be met
- more potent means that it takes less of the drug to have an impact
efficacy
the plateau that is reached, the maximum response that can be reached by a drug
allele
variant forms of a gene
allosteric proteins
one that has an effector which regulates its activity by acting on a site physically distant from the proteins ligand-binding site
- protein function is a mechanism by which an event in one place of a protein structure causes an effect at another site
amino acids
organic compounds that contain both amino and carboxylic acid functional groups
- build muscles, cause chemical reactions, transport nutrients, and prevent illness
catalyst
a substance that increases the rate of a chemical reaction without itself undergoing any permanent chemical change
central dogma of molecular biology
a theory stating that genetic information flows in only one direction, from DNA to RNA to protein, or from RNA to protein
chromatin
the material of which the chromosomes of organisms other than bacteria are composed. consists of protein, RNA, and DNA
codon
a sequence of three nucleotides which together form a unit of genetic code in a DNA or RNA molecule
energy of activation
the minimum amount of energy that is required to activate atoms or molecules to a condition in which they can undergo chemical transformation or physical transport
enzyme
a substance produced by a living organism which acts as a catalyst to bring about a specific biochemical reaction
gene-environemtn interaction
the interaction between genes and the environment shape human development
kinase
an enzyme that catalyses the transfer of a phosphate group from atp to a specified molecule
-Catalyzes the transfer of phosphate groups from high energy, phosphate donating molecules to specific substrates. This process is known as phosphorylation, where the high-energy ATP molecule donates a phosphate group to the substrate molecule
lysosomes
a membrane bound cell organelle that contains digestive enzymes, they break down excess or worn out cell parts
peptides
a short chain of amino acids linked by chemical bonds, a longer chain is a polypeptide
phosphorylation
addition of a phosphoryl group to a molecule, this reaction is vital for the cellular storage and transfer of free energy using energy carrier molecules
polymers
any of a class of natural or synthetic substances composed of very large molecules, called amcromolecules
polymorphisms
presence of two or more variant forms of a specific DNA sequence that can occur among different individuals or populations
action potental
a sudden, fast, transitory, and propagating change of the resting membrane potential. Only neurons and muscle cells are capable of generating an action potential; that property is called the excitability
Nerve signals generate by neurons and are conducted along processes
Caused by a stimulus with a certain value
Three phases: depolarization, overshoot, and repolarization
amplification
increasing a signal so that minimal receptor occupation by small amounts of neurotransmitters in the synapse produces significant cellular responses
anticholinergic
drugs that block and inhibit the activity of the neurotransmitter acetylcholine at both central and peripheral nervous system synapses
anticholinesterase
drugs that prolong the existence of acetylcholine after it is released from cholinergic nerve endings by inhibiting both acetylcholinesterase and butyrylcholinesterase
autoreceptors
a receptor located on the neuron and the function is to bind to a specific ligand (such as neurotransmitters or hormones) released by that same neuron. The autoreceptor is mainly used as a feedback mechanism to monitor neurotransmitter synthesis and/or release
excitatory synapse
a synapse in which an action potential in a presynaptic neuron increases the probability of an action potential occurring in a postsynaptic cell
Neurons form networks through which nerve impulse travel, each neuron often making connections with other cells
exocytosis
a process by which the contents of a cell vacuole are released to the exterior through fusion of the vacuole membrane with the cell membrane
g protein
a family of proteins that act as molecular switches inside cells, and are involved in transmitting signals from a variety of stimuli outside a cell to its interior
Convert extracellular signals into intracellular responses, including responses to hormones, neurotransmitters, as well as responses to vision, olfaction, and taste
hyperpolarization
when the membrane potential becomes more negative at a particular spot on the neuron’s membrane, while depolarization is when the membrane potential becomes less negative
inhibitory postsynaptic potential
a temporary hyperpolarization of the postsynaptic membrane caused by the flow of negatively charged ions into the postsynaptic cell. An IPSP is received when an inhibitory presynaptic cell is connected to the dendrite, fires and action potential
inhibitory synapse
a specialized type of junction at which activity from one neuron (in the form of an action potential) reduces the probability of activity in an adjacent neuron by initiating an inhibitory post synaptic potential
ionotropic receptors
ligand-gated ion channels made up of 3-5 protein subunits that together form an ion-conducting pore in the center of the receptor. There are four families of ionotropic receptors which differ in their molecular structure and the ligands that open them
Utilized by the nervous system with the metabotropic receptors
Membrane potential = a potential gradient that forces ions to passively move in one direction: positive ions are attracted by the “negative” side of the membrane and negative ions by the positive one
Electrical potential difference
metabotropic receptors
also referred to by the broader term G-protein-coupled receptor, is a type of membrane receptor that initiates a number of metabolic steps ot modulate cell activity
Utilized by the nervous system with the ionotropic receptors
multipolar cell
the most common type of neurons in the human body, they are present throughout a persons central nervous system, including the brain and associated nerves in the ANS.
Possess a single axon and many dendrites, allowing for the integration of a great deal of information
muscarinic
receptors that are abundantly expressed through the brain, tissues, bladder, pulmonary system, and more.
They are involved in the transduction of cholinergic signals in the CNS, autonomic ganglia, smooth muscles, and other parasympathetic end organs
Respond more slowly than nicotinic receptors, may be excitatory or inhibitory
myelin sheath
an insulating layer around the nerves that allows electrical impulses to transmit quickly and efficiently along the nerve cells.
Na+ - K+ atpase
helps to maintain osmotic equilibrium and membrane potential in cells the sodium and potassium move against the concentration gradients.
neural integration
a process during which the electrochemical weighing of competing and canceling membrane potentials is resolved, leading to a neuron firing (excitatory) or not firing (inhibitory or subthreshold).
nicotinic
receptors that can be found throughout the nervous system as well as in muscles
Trigger rapid neural and neuromuscular transmission. Found in the somatic nervous system, and the sympathetic and parasympathetic nervous systems
Modifies the sate of neurons through two main mechanism → the movement of cations causes a depolarization of the plasma membrane leading to the activation of voltage gated ion channels
oligodendroglia
form and maintain the myelin that surrounds processes of CNS neurons
schwann cells
the major glial cell type in the peripheral nervous system. They play essential roles in the development, maintenance, function, and regeneration of peripheral nerves
refractory period
the period of time during which a cell is incapable of repeating an action potential
spatial summation
when progressively larger number of primary afferent neurons are activated simultaneously, until sufficient neurotransmitter is released to activate an action potential in the postsynaptic neuron
