NR 565 MidTerm
Review
1. G-Protien coupled receptors and how they interact with drugs
G-protein coupled receptors (GPCR) interact with drugs through 7 regions of
proteins that span and innervate the cell membrane, and trap the molecule into the
receptor site like an interwoven basket (Insel & Sriram, 2018). Drugs can then enter this
space and interact with the GRCP. A specific interaction and binding with a site on one
or more of the regions of proteins within the GPCR, and drugs bound with the GRCP
can stimulate the release of G proteins that can interact with various effector proteins to
create physiological responses within the body (Insel & Sriram, 2018). This process
occurs through secondary messengers (such as cAMP) which creates the extracellular
interactions produced by the drug binding to the GRCP.
2. What neurotransmitters are excitatory?
amino acids such as glycine, aspartate, and glutamate are excitatory (Woo &
Robinson, p.16, 2016).
3. Which is the most common CYP enzyme in the body? What role does it
play?
According to the textbook, the CYP3A4 is the most important enzyme in the body.
CYP3A4 is responsible for the metabolism of more than 50% of medications and is
considered a major drug metabolizing enzyme. CYP3A4 can be found in the liver, as
well as the lining of the GI tract. Due to this location, food can also influence this CYP.
One example of this is grapefruit juice, which can inhibit CYP3A4. Medications that are
metabolized by CYP3A4 include antimicrobials, calcium channel blockers,
antihistamines, anticonvulsants, azole antifungals, and corticosteroids (Woo, &
Robinson, 2016).
4. What is the clinical significance of being an ultra-rapid CYP2D6
metabolizer?
People who are ultra-rapid metabolizers have high activity of CYP2D6 enzymes that
break down certain medicines rapidly and are likely to need different doses or even a
different medicine. Drug dose, response, and toxicity risk of beta-blockers,
antidepressants, antiarrhythmics, and opioid analgesics are dependent on CYP2D6
pharmacogenetics (Ayazseven et al., 2020). Knowing the result of the CYP2D6 test and
which group the patient falls into such as poor metabolizers, intermediate metabolizers,
or ultra-rapid metabolizers, will help nurse practitioners prescribe the right medication
and dosage for the patient.
5. What would be the concern if a drug is a CYP450indicer? How that might
affect the metabolism of other drug the patient is taking?
Cytochrome P450 enzymes are in cells throughout the body, primarily found in liver
cells (Girvan & Munro, 2016). These enzymes are essential for the metabolism of many
medications. Cytochrome P450 enzymes can act as an inducer or inhibitor of
metabolism. When a medication induces the CYP450 enzyme that increases the rate of
, metabolism (Girvan & Munro, 2016). This can impact the effectiveness of other
medications. For example, medication A induces CYP450 enzyme activity, therefore
medication B will be metabolized quicker and have a less therapeutic effect.
6. Explain the significance of a drug being an inhibitor of P-glycoprotein?
(see text)
P-glycoprotein (P-gp) is the main barrier of the body and it affects the proper delivery
of drugs and causes drug resistance in our body. P-gp is an efflux membrane
transporter, that can be found throughout the body and it controls the cellular uptake
and the distribution of synthetic substances, chemicals, and toxins. Drugs are chemicals
and P-gp hinders the absorption, permeability, and retention of the drugs, extruding
them out of the cells. This adversely affects drug therapies and fails to yield good
results, for example in therapies like using chemo agents in cancer treatments. In this
case, proper inhibition of P-gp is important to increase cellular uptake, transport, and
half-lives of drugs. The drug is an inhibitor of P-gp that would help in the cost-effective
treatment for disease conditions without wasting an extra amount of medicines. It will
help to shorten the treatment time and speedy recovery of the patient (Abebe et al.,
2019; Woo & Robinson, 2016).
7. Significance of a VCORC1 mutation for patients taking warfarin?
In 2008, the U.S Food and Drug Administration updated the dosing of warfarin to
include the application of pharmacogenomics. Variable metabolism by CYP2C9 was
once known as the major contributor to the variable response to warfarin. However, a
mutation in VCORC1 has been found to account for much more variability in warfarin
responses and can cause a rare syndrome of warfarin resistance. A mutation in
VCORC1 encodes a subunit of the vitamin K epoxide reductase complex ,the
pharmacological target for warfarin, and increases the chances of uncontrolled bleeding
(Woo & Robinson, 2016). Therefore, if providers have information about the presence of
this mutation, they may decide to decrease the dosage of Coumadin for their patient.
8. What out text has to say about National Standards of Culturally and
Linguistically Appropriate Services?
In 2012, the institute of medicine identified that the main factor affecting health
disparity is cultural competency of the health practitioner (Woo & Robinson, 2016). The
National Standard for Culturally and Linguistically Appropriate Services in health and
health care (CLAS) standards were created as a way to address and correct these
inequities (Woo & Robinson, 2016). Originally established in 2000, the CLAS standards
provided a blueprint for providers to implement services that were culturally and
linguistically appropriate, however, over the years they have evolved (Woo & Robinson,
2016). They have undergone review and have been revised in 2013 and will continue
to evolve in response to research and changing demographics (Woo & Robinson,
2016).
Review
1. G-Protien coupled receptors and how they interact with drugs
G-protein coupled receptors (GPCR) interact with drugs through 7 regions of
proteins that span and innervate the cell membrane, and trap the molecule into the
receptor site like an interwoven basket (Insel & Sriram, 2018). Drugs can then enter this
space and interact with the GRCP. A specific interaction and binding with a site on one
or more of the regions of proteins within the GPCR, and drugs bound with the GRCP
can stimulate the release of G proteins that can interact with various effector proteins to
create physiological responses within the body (Insel & Sriram, 2018). This process
occurs through secondary messengers (such as cAMP) which creates the extracellular
interactions produced by the drug binding to the GRCP.
2. What neurotransmitters are excitatory?
amino acids such as glycine, aspartate, and glutamate are excitatory (Woo &
Robinson, p.16, 2016).
3. Which is the most common CYP enzyme in the body? What role does it
play?
According to the textbook, the CYP3A4 is the most important enzyme in the body.
CYP3A4 is responsible for the metabolism of more than 50% of medications and is
considered a major drug metabolizing enzyme. CYP3A4 can be found in the liver, as
well as the lining of the GI tract. Due to this location, food can also influence this CYP.
One example of this is grapefruit juice, which can inhibit CYP3A4. Medications that are
metabolized by CYP3A4 include antimicrobials, calcium channel blockers,
antihistamines, anticonvulsants, azole antifungals, and corticosteroids (Woo, &
Robinson, 2016).
4. What is the clinical significance of being an ultra-rapid CYP2D6
metabolizer?
People who are ultra-rapid metabolizers have high activity of CYP2D6 enzymes that
break down certain medicines rapidly and are likely to need different doses or even a
different medicine. Drug dose, response, and toxicity risk of beta-blockers,
antidepressants, antiarrhythmics, and opioid analgesics are dependent on CYP2D6
pharmacogenetics (Ayazseven et al., 2020). Knowing the result of the CYP2D6 test and
which group the patient falls into such as poor metabolizers, intermediate metabolizers,
or ultra-rapid metabolizers, will help nurse practitioners prescribe the right medication
and dosage for the patient.
5. What would be the concern if a drug is a CYP450indicer? How that might
affect the metabolism of other drug the patient is taking?
Cytochrome P450 enzymes are in cells throughout the body, primarily found in liver
cells (Girvan & Munro, 2016). These enzymes are essential for the metabolism of many
medications. Cytochrome P450 enzymes can act as an inducer or inhibitor of
metabolism. When a medication induces the CYP450 enzyme that increases the rate of
, metabolism (Girvan & Munro, 2016). This can impact the effectiveness of other
medications. For example, medication A induces CYP450 enzyme activity, therefore
medication B will be metabolized quicker and have a less therapeutic effect.
6. Explain the significance of a drug being an inhibitor of P-glycoprotein?
(see text)
P-glycoprotein (P-gp) is the main barrier of the body and it affects the proper delivery
of drugs and causes drug resistance in our body. P-gp is an efflux membrane
transporter, that can be found throughout the body and it controls the cellular uptake
and the distribution of synthetic substances, chemicals, and toxins. Drugs are chemicals
and P-gp hinders the absorption, permeability, and retention of the drugs, extruding
them out of the cells. This adversely affects drug therapies and fails to yield good
results, for example in therapies like using chemo agents in cancer treatments. In this
case, proper inhibition of P-gp is important to increase cellular uptake, transport, and
half-lives of drugs. The drug is an inhibitor of P-gp that would help in the cost-effective
treatment for disease conditions without wasting an extra amount of medicines. It will
help to shorten the treatment time and speedy recovery of the patient (Abebe et al.,
2019; Woo & Robinson, 2016).
7. Significance of a VCORC1 mutation for patients taking warfarin?
In 2008, the U.S Food and Drug Administration updated the dosing of warfarin to
include the application of pharmacogenomics. Variable metabolism by CYP2C9 was
once known as the major contributor to the variable response to warfarin. However, a
mutation in VCORC1 has been found to account for much more variability in warfarin
responses and can cause a rare syndrome of warfarin resistance. A mutation in
VCORC1 encodes a subunit of the vitamin K epoxide reductase complex ,the
pharmacological target for warfarin, and increases the chances of uncontrolled bleeding
(Woo & Robinson, 2016). Therefore, if providers have information about the presence of
this mutation, they may decide to decrease the dosage of Coumadin for their patient.
8. What out text has to say about National Standards of Culturally and
Linguistically Appropriate Services?
In 2012, the institute of medicine identified that the main factor affecting health
disparity is cultural competency of the health practitioner (Woo & Robinson, 2016). The
National Standard for Culturally and Linguistically Appropriate Services in health and
health care (CLAS) standards were created as a way to address and correct these
inequities (Woo & Robinson, 2016). Originally established in 2000, the CLAS standards
provided a blueprint for providers to implement services that were culturally and
linguistically appropriate, however, over the years they have evolved (Woo & Robinson,
2016). They have undergone review and have been revised in 2013 and will continue
to evolve in response to research and changing demographics (Woo & Robinson,
2016).
