PCOL M1.3 part 1 Flashcards
What is the relationship of Pk, Pd, Physico-chemical properties
reversible
describes the actions of a drug on the body and the influence of drug concentrations on the magnitude of the response.
Pharmacodynamics
The drug–receptor complex initiates alterations in biochemical and/or molecular activity of a cell by a process called ——
signal transduction
3 aspects on how a drug works
Physico-chemical properties
Pharmacodynamics
Pharmacokinetics
The intensity and quality of effect
Pharmacodynamic properties
it is depended to the physical and chemical of the drug
Ex. The drugs become bioavailable when the drugs cross the membrane.
Pharmacokinetics properties
The Chracteristic Pharmacokinetics properties is when a drug that capable of crossing the membrane more rapidly and efficiently is when it is
lipophilic, unionized, lower size of molecular weight
in the systemic circulation [pagnandoon na sya sa katawan] then it is able to bridge the site of action called DISTRIBUTION
- Bioavailable
—–it is the metabolism and excretion [determine by ——-
- Clearance and physiochemical properties
– is the connection between the brainstem and the spinal cord
medulla oblongata
include cardiovascular receptors, respiratory, and vasomotor centers
o depression
What do you called Blood Brain barrier that separation of CNS
parenteral system [outside the central nervous system]
- drugs may increase or enhance the function of an organ or a system. And give Example of drug that can cause stimulation of CNS
- STIMULATION - Caffeine
- drugs inhibit or decrease the function of an organ or the system
- DEPRESSION - drugs inhibit or decrease the function of an organ or the system
example of CNS depressant, it decreases the activity of the CNS leading to drowsiness, decrease concentration, affect balance and equilibrium and even decrease memory and learning functions.
Alcohol
– memory/learning
o Cerebral cortex
this is an action attributed to local affects of the drug to a tissue or cell and example and explain
- IRRITATION
laxatives promote peristaltic movement by irritating the wall of the GIT causing increase motility and evacuation
is a laxative is used treat constipation
SENNA
intended; it is usually the desired effect that leads to its therapeutic use
- PRIMARY
is unintended; commonly leading to undesired effects (side effects, adverse drug reactions)
- SECONDARY
- Alter the cell environment by physical or chemical processes
- Example and explain
Structural nonspecific
the patient has hyperacidity - the action of antacid is a bases that will lead (alters the pH of the stomach); to ‘neutralized’ [pagacidic yung patient need nya ng antacid para magneutralized]
* ‘hyperacidity – mataas ang acid than normal’
* there is hyperacidity = higher stimulation = nagkakaroon ng depress
* action of antidotes, e.g., activated charcoal (adsorbs the toxins by the process of absoption)
- Alter cell function by drug-receptor interactions
- Majority of drugs’ action is through this mechanism
- treat for ulcer is what
Structural specific
Omeprazole – proton bound inhibitor [push the acid] – disable the proton bound in the cell
2 target for drug action
protein and non protein target
Majority of drugs interact with protein targets such as —- or 4 Regulatory Protein as Primary Target for Drug Action
receptors, ion-channel, enzymes and carrier molecules/Transporters
. After interacting with the target, a ——-of event follows
cascade
Structural specific mechanism
Protein target
Structural nonspecific mechanism
Non-protein target
Non-protein target can be the target for the drug action
o Binding
o Per drug may exhibit neutralizing effect
o It promotes osmosis
possible events that will follow the interaction
o Agonist/ inverse agonist
- possible events that will NOT follow the interaction / NO EFFECT
o Antagonist
They promote permeability of the union/they modulate the permeability of union
o Blockers
o Modulators
B. Ion channels
C. Enzyme - Normal reaction inhibited
o Inhibitors
C. Enzyme - Abnormal metabolite produced
o False substrate
C. Enzyme - Active drug produces
o Prodrug
- Any target molecule with which a drug molecule has to combine in order to elicit its specific effect
- It is the component of a cell or organism that interacts with a drug and initiates the chain of events leading to the drug’s observed effects. [describes it as a target for drug’s action.]
RECEPTOR
o Drug bind to the receptor/ positive
o is the capacity of a drug to form the complex with its receptor (DR complex)
AFFINITY
o it is the ability of a drug to trigger the pharmacological response after making the drug-receptor complex
INTRINSIC ACTIVITY (OR) EFFICACY
o refers to any molecule which attaches selectively to particular receptors or sites
o it is a drug, natural or any substrate if it matches to a specific receptor
LIGAND
o refers to an agent which activates a receptor to produce an effect similar to that of the physiologic signal molecule.
o It has both high affinity as well as high intrinsic activity, therefore can trigger the maximal biological response
o It has affinity and efficacy
AGONIST (Positive)
Agent which activates a receptor to produce an effect in the opposite direction to that of the agonist
Have full affinity but intrinsic activity ranges between 0 to -1
Inverse (Negative) agonists
o an agent which prevents the action of an agonist on a receptor but doesn’t have any effect of its own.
o It has only affinity but no intrinsic activity [no response/efficacy].
o This drug binds to the receptor and blocks the binding of an endogenous agonist.
ANTAGONIST
o Agent which activates a receptor to produce a sub maximal effect but antagonizes the actions of full agonist
o Have full affinity but with low intrinsic activity and hence are only partly as effective as agonists
PARTIAL AGONIST
o so-called because their ligands are presently unknown, which may prove to be useful targets for the development of new drugs
o coded
o No particular receptor of this drug
“ORPHAN” RECEPTOR
o the best characterized receptors
o modify the actions of endogenous chemical signals
neurotransmitters [ex. NE]
autacoids [Histamine, serotonin]
hormones [estrogen, thyroid hormones]
- REGULATORY PROTEINS
Types of protein
Enzymes , Transport proteins, receptor, and Structural proteins
- Also known as ligand gated ion channels, or transmitter operated channels
. RECEPTOR-OPERATED CHANNEL (ROC)
- Directly linked to a receptor, and opens only when the receptor is activated
. RECEPTOR-OPERATED CHANNEL (ROC)
receptor for Na+ ion channel
- Nicotinic receptor
receptor for Cl- ion channel
GABAA receptor
o Closed, but openable in response to an appropriate stimulus
- Rested
o Closed, and unable to open in response to an appropriate stimulus for a rested state channel
- Inactivated
open/ capable of opening the channel
- Activated
ROC behavior has 3 recognized states
- Rested, Activated, and Inactivated
molecular mechanism of action that involves modulation of the transition of the ROC between states
- GATING
4 example of VOLTAGE-OPERATED CHANNELS (VOC)
o Na channel (cardiac), Ca channels, K channels, and other channels
- The behavior is modulated endogenously by membrane potential
VOLTAGE-OPERATED CHANNELS (VOC)
o 5 types Ca channels
L [heart],
T[Brain],
N, P, Q
- Are sometimes called metabotropic receptors
G-PROTEIN COUPLED RECEPTORS
- Are receptors for many hormones and slow transmitters
G-PROTEIN COUPLED RECEPTORS
e.g. muscarinic Ach receptor, adrenergic receptors and neuropeptide receptors
- Are membrane receptors which are coupled to intracellular effector systems via —-
G-protein
