Chapter 10 Flashcards
Introduction into pharm (26 cards)
Deffinion of Pharmacodynamics
as medication is administered, it begins to alter a function or process within the body. simply put by binding to a regulatory molecules (proteins) and activating (turning on) or inhibiting (turning off) normal body process.
What is classified as a drug?
a drug is ANY substance that interacts with a molecule or protein that plays a regulatory role in living systems. Drugs MUST have a SPECIFIC size, charge, and shape to interact with a given receptor.
What is a receptor?
A receptor is a specific molecule, usually a protein, that interacts with a specific chemical in regulatory function. Receptors are responsible for the selectivity of drug action.
Endogenous
A substance made inside the body. endo, meaning inside, genous meaning from the beginning
Exogenous
A substances made outside the body. Exo, meaning outside the body.
What are hormones?
hormones are endogenous drugs made naturally inside the body.
Alpha (a)-1 Receptors
causes vasoconstriction of arteries and veins. Agonist Effect
Alpha (a)-2 Receptors
insulin restriction, glucagon secretion, inhibition of norepinephrine. Agonist Effect
Beta (b)-1 Receptors
increases heart rate, increases myocardial contractility, increases myocardial conduction, and renin secretion for urinary retention. Agonist Effect
Beta (b)-2 Receptors
Bronchus and Bronchiole reaction, insulin secretion, uterine relaxation, arterial dilation in certain key organs. Agonist Effect
Dapaminergic Receptors
vasodilation of renal and mesenteric arteries. Agonist Effect
Nicotinic Receptors
present at neuromuscular junction, allowing acetylcholine (ACh) to stimulate muscle contractions. Agonist effect
Muscarinic -2 Receptors
present in the heart; activated by ACh to effect sympathetic stimulation, decreasing heart rate, contractility, and electrical conduction velocity. Agonist Effect
Agonist Receptors
Is ANY drug that binds to a receptor and activates (starts) the receptor. in many receptors agonist leaving the binding site deactivated the receptor. however, in other agonist receptors, can permanently activates the receptors. Aspirin is an example.
Antagonist Receptors
Is ANY drug that binds to a receptor and PREVENTS (stops) the activation of the receptors.
Competitive Antagonist Receptors
Is ANY pharmacological Antagnoist that “competes” with the binding of against at the binding site.
Noncompetitive Antagonist Receptors
Is ANY pharmacological antagonist that binds to a site on the receptor OTHER THAN the agonist binding site. it deactivate the receptors
Physiologic Antagonist Receptors
When there is an EXCESS Histamine released by the body is a problem. Epinephrine is given to COUNTERACT the effect of the histamine
Drug Receptor Interactions
Drugs interact with receptors by means of chemical forces or bonds: Covalent (permanently changing the receptors), Electrostatic (positives connecting to negatives), Hydrogen (hydro to nitro, or hydro to oxygen), lipophilic.
Meaning of Affinity
How tightly the receptors binds to the drug
Meaning of Bioavailability
Describes the concentration of drug in systemic blood in relation to amount of drug given.
IV Bioavailability
100% bioavailability, because it is given directly into the blood.
PO Bioavailability
ranges 10%-50% bioavailability, because blood from the GI tract goes directly to the liver. where first pass metabolism takes place.
First Pass Effect
all drugs absorbed by GI tract enter the portal blood supply, and go directly to the liver. the liver metabolites many drugs before the enter the systemic blood supply.
