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Clincial Correlates Exam 2 - Chapter 11
Biochem
94
Other
Graduate
10/12/2009

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Term
In congenital adrenal hyperplasia, there is a deficiency of what?
Definition
CYP21A2
Term
This is a major site of steroid hormone production during fetal and adult life and is more active in fetal life?
Definition
Adrenal cortex
Term
The adrenal cortex may produce ____ mg of _______ per day in comparison to _____ mg in the nonstressed adult adrenal gland?
Definition
100-200; steroids; 20-30
Term
T/F: Enzyme deficiencies are reported at only certain steps of cortisol production?
Definition
False: Enzyme deficiencies have been reported at all steps of cortisol production.
Term
Diseases associated with insufficient cortisol production are referred to as __________________?
Definition
Congenital Adrenal Hyperplasias (CAH)
Term
The most common enzyme deficiency in congenital adrenal hyperplasias is?
Definition
17alpha-hydroxyprogesterone to 11-deoxycortisol, which is converted by CYP11B1 to cortisol
Term
What is the pituitary hormone that regulates production of cortisol?
Definition
ACTH
Term
Because there is not enough _____, secretion of ACTH increases.
Definition
Cortisol
Term
Prolonged periods of elevated ACTH levels cause ______ and an increased production of the adrogenic hormones, _______ and ________.
Definition
adrenal hyperplasia; DHEA; androstenedione
Term
The additional production of ________ steroids causes virilization in females, preocious sex organ develoment in prepubertal males, or disease related to salt imbalance because of decreased levels of ________.
Definition
adrogenic; aldosterone
Term
Clinical consequences of severe _______ deficiency may be recognizable at birth, particularly in females, because the excessive buildup of androgenic steroids may cause obvious irregular development of _____?
Definition
21-hydroxylase; genitalia
Term
In male newborns, a deficiency of 21-hydroxylase activity may be overlooked because male _____ appear normal, but there will be _________ and physical development later on.
Definition
genitalia; preocious masculinization
Term
In late onset congenital adrenal hyperplasias include early development of _____, early fusion of ______ causing premature cessation of growth, male _____ patterns in females.
Definition
pubic hair; epiphyseal growth plates; baldness
Term
CYP450 plays a major role in ______ synthesis?
Definition
Estrogen
Term
During _______, a unique interaction among CYP450 in different organs is needed to synthesize the large quantities of steroids that are required.
Definition
Pregnancy
Term
Steroid hormone production increases dramatically and, at term, reaches ____ mg of estradiol, ____ mg of estriol, and ____ mg of progesterone per day, amounts that are a _____ times greater than those produced by premenopausal, nonpregnant women.
Definition
15-20; 50-100; 250; 1000
Term
The major site for estrogen production in the first few weeks of pregnancy is?
Definition
The corpus luteum of the ovary
Term
At approximately __ weeks of gestation, the _____ begins synthesizing and secreting progesterone and estrogens.
Definition
4; placenta
Term
After __ weeks of gestation, the _____ becomes the dominant source of progesterone?
Definition
8; placenta
Term
The human placenta lacks ____, which catalyzes both the 17alpha-hydroxylation reaction and the cleavage of the C17-C20 bond and thus cannot synthesize _____ from cholesterol?
Definition
CYP17; estrogens
Term
The placenta can catalyze the side-chain cleavage reaction to form _____ from cholesterol and oxidizes that to ______, which is secreted into the maternal circulation.
Definition
pregnenolone; progesterone
Term
Since the placenta cannot synthesize DHEA or androstenedione from progesterone, The fetal _____ gland catalyzes the synthesis of ____ from cholesterol and releases it into the fetal circulation.
Definition
adrenal; DHEA
Term
A large proportion of fetal DHEA is metabolized by the fetal adrenal and liver to 16alpha-hydroxy-DHEA, which is converted by _____ in the placenta to the estrogen _____. This is example of the cooperativity of the CYP450-mediated _____ systems leading to the formation of ______ during gestational development
Definition
CYP19; estriol; hydroxylating; estrogens
Term
The role that CYP450 play in drug metabolism and the serious consequences of drug-drug interaction were clearly shown for two drugs: _____(Seldane) and ____ (Propulsid), when their metabolism was inhibited by other drugs.
Definition
Terfenadine; cisapride
Term
A small percentage of terfenadine and cisapride users experienced severe adverse effects that forced the manufacturers and FDA to issue warning that the drugs should not be taken with other drugs that inhibit ____ and had to be taken off the market.
Definition
CYP3A4
Term
Tefenadine, a second generation ______ was approved in 1985 to treat _____.
Definition
H1 anti-histamine; seasonal allergies
Term
Terfenadine is rapidly metabolized in the liver by CYP3A4 to ______, resulting in low levels of the parent drug soon after ingestion, but the therapeutic effects of terfenadine are actually caused by ______.
Definition
fexofenadine; fexofenadine
Term
Because many other drgs are substances or inhibitors of CYP3A4, the metabolism of ______ is potentially inhibitable.
Definition
terfenadine
Term
Those who took terfenadine with the macrolide antibiotic ______ or the anti-fungal agent, ______, both strong inhibitors of _______, had significantly elevated plasma levels of terfenadine.
Definition
erythromycin; ketoconazole
Term
In a small % of terfenadine users, serious ________ problems developed because the parent drug caused alteration in in cardiac _____ channels and increased the risk of a rare ventricular tachycardia called _________.
Definition
cardiac; potassium; Torsades de Pointes
Term
T/F: Some individuals died from cardiac problems that developed after taking terfenadine with erythromycin or fexofenadine?
Definition
False; erythromycin or ketoconazole NOT fexofenadine.
Term
Since the therapeutic properties of terfenadine were associated with its nontoxic ______, fexofenadine, the manufacturer tested fexofenadine as a new medication and sought FDA approval, now marketed as _______.
Definition
metabolite; Allegra
Term
Cisapride was approved in 1993 for patients who suffer _____ as a result of gastroesophageal reflux disease (GERD).
Definition
nighttime heartburn
Term
The elimination of Cisapride from the body is dependent on _____ metabolism, and when administered alone or with drugs that do not inhibit the above blank, the parent drug does not accumulate in the ___.
Definition
CYP3A4; plasma
Term
When taken with drugs that are substrates or inhibitors of ______, cisapride metabolism is ______, and it accumulates with subsequent intake.
Definition
CYP3A4; reduced
Term
In some individuals, increased cisapride levels cause _______ and by the end of 1999, _____ abnormalities were reported in 341 patients, resulting in 80 deaths. Cisapride marketing was stopped after 2000.
Definition
cardiac arrythmias; heart rhythm
Term
Acetaminophen is one of the most commonly used ____ (pain-relieving) and _____ (fever-reducing) OTC medication.
Definition
analgesic; antipyretic
Term
Acetaminophen is available alone or as a component of more than ______ other nonprescription medications.
Definition
100
Term
The consumption of ____, an induced and substrate of _____, has a profound effect on acetaminophen.
Definition
alcohol; CYP2E1
Term
Drinking a 750-mL bottle of wine, six 12-oz. beers, or 9 oz. 80-proof liquor, over a 6-7 hour period causes a 22% increase in ____-mediated metabolism of acetaminophen that manifests several hours post alcohol intake.
Definition
CYP2E1
Term
T/F: Timing is very critical between alcohol consumption and intake of acetaminophen in the development of acetaminophen-induced liver injury.
Definition
True
Term
In a person drinking alcohol, metabolism of acetaminophen taken shortly after cessation of drinking is delayed because ____, like acetaminophen is a substrate for CYP2E1, and therefore competes for binding.
Definition
ethanol
Term
In chronic alcohol consumption, CYP2E1 is induced and greater amounts of _______ are produced; however, alcohol may actually ____ the liver from acetaminophen-induced injury, if taken at the same or shortly before.
Definition
N-acetyl-p-benzoquinoneimine (NAPQI); protect
Term
If acetaminophen is taken several hours post alcohol intake, the alcohol has already been metabolized and increased levels of ____ are then available to metabolize acetaminophen to _____, increasing the risk of ____ damage.
Definition
CYP2E1; NAPQI; liver
Term
The length of time and amount of alcohol consumed daily affect the amount of CYP2E1 expressed in ________.
Definition
hepatocytes
Term
T/F: The amount of acetaminophen consumed is also a major determining factor for risk, as normally recommended doses usually generate sufficient NAPQI to produce liver cell damage.
Definition
False - recommended dosages do NOT usually generate sufficient NAPQI to produce liver cell damage.
Term
Why does higher doses of acetaminophen increase the risk of liver cell injury?
Definition
More drug will be metabolized through the CYP2E1 pathway
Term
Both the ______ and ______ pathways are essential in determining the amount of acetaminophen that will be metabolized by CYP2E1
Definition
Sulfation; glucuronidation
Term
The levels of intracellular _____ are critical as it forms conjugates with NAPQI to protect the liver from this reactive metabolite.
Definition
glutathione
Term
In the present of high levels of ____, the glutathione is rapidly depleted and can no longer protect against damage.
Definition
NAPQI
Term
Induction of CYP450 may decrease the therapeutic effects of drugs, because increases in liver P450 levels increase rates of ____, and, therefore, _____ and/or excretion of drugs.
Definition
metabolism; inactivation
Term
Induction of the P450 system may also have adverse effects due to the increased formation of toxic ________.
Definition
metabolites
Term
Induction of CYP3A4 by the anti-tuberculosis drug, __________, may greatly increase elimination of the oral contraceptive ethinyl _____, causing subeffective plasma levels of the drug, which increases the risk of ______.
Definition
rifampin; estradiol; pregnancy
Term
Treatment with the anticonvulsant drugs, ______ and ___________, may also induce CYP3A4 and reduce the ________ potency of ethinyl estradiol.
Definition
Phenytoin; carbamazepine; contraceptive
Term
It is imperative that a women taking ethinyl ________ as an oral contraceptive simultaneously with a CYP3A4 inducer _______ (increase/decrease) the dose of the contraceptive or use an alternative contraceptive method or drug.
Definition
estradiol; increase
Term
The herbal agent, ____, also induces CYP3A4 activity, raising concerns who those who ingest the herb may not receive the therapeutic benefits of drugs that are CYP3A4 substrates.
Definition
St. John's Wort
Term
A reduction in _____ levels of oral contraceptives, HIV anti-protease drugs, the immunosuppressive drug ______, or certain _____ drugs, used to lower cholesterol levels, can occur because each of these drugs is a ______ for CYP3A4.
Definition
plasma; cyclosporine; statin; substrate
Term
Because ____ is considered a natural substance, individuals may take this agent without notifying their physician or knowing its effects.
Definition
St. John's Wort
Term
Multiple alleles have been demonstrated for approximately ___% of human P450 genes. These genetic polymorphisms may produce defective _______.
Definition
40; P450 proteins
Term
Why would the absence of CYP450 activity cause many problems?
Definition
Due to the accumulation of therapeutic drugs that cannot be metabolized
Term
The discovery of exaggerated hypotensive effects with the antihypertensie drug, ______, led to the characterization of individuals who inefficiently metabolized ______ substrates.
Definition
debrisoquine; CYP2D6
Term
About 4-50% of caucasion, 8% of african and african-american, and 1% of asian polulations are deficient in catalytically active ______.
Definition
CYP2D6
Term
The drugs sparteine, amitriptyline, dextromethorphan, and codein are metabolized by?
Definition
CYP2D6
Term
In the case of codein, CYP2D6 in normal individuals catalyzes the ______ of approximately 10% of the codein to morphine, so individuals who lack function CYP2D6 are unstable and do not achive the _____ effects of codein.
Definition
O-demethylation; analgesic
Term
A genetic polymorphism associated with CYP2C19 has been demonstrated in individuals who are poor metabolizers of _____, a drug used in the treatment of epilepsy. CYP2C19 hydroxylates C4 of the S-enantiomer of mephenytoin to inactive the phsyiological effort.
Definition
Mephenytoin
Term
Approximately 14-22% of Asian, 4-7% of the African and African-American, and 3% of the Caucasion populations lack the active form of _____.
Definition
CYP2C19
Term
CYP2C9 is rear in all ethnic groups, and its absence may have serious consequences in the metabolism of ____, an orally administered drug used to inhibit blood coagulation in patients who have suffered a heart attack or stroke to prevent clots.
Definition
S-Warfarin
Term
Warfarin is metabolized by ____ for elimination and excess amounts can cause uncontrollable bleeding and possibly death.
Definition
CYP2C9
Term
CYP2C9*3 is an allilic variant in which ___ is substituted for leucine at residue 359, resulting in substantial loss of enzymatic activity.
Definition
isoleucine
Term
Individuals deficient in CYp2C9 may require only 0.5-1 mg of warfarin per week in contrast to the _____ mg/day for those with normal CYP2C9; If that dose of warfarin was taken by someone lacking functional CYP2C9, uncontrollable bleeding could result.
Definition
4-5
Term
The levels of cyclic nucleotides (____ and ___) present in the cell are dependent not only on their formation by adenylate or guanylate cyclase, but also on their degradation by ____, which hydrolzye them to 5'-nucleotides and so play a critical role in the modulation of these second messenger signaling pathways.
Definition
cGMP; cAMP; phosphodiesters (PDEs)
Term
The inhibition of ____ destruction of cyclic nucleotides would thus prolong the physiological response elicited by the cyclic nucleotides.
Definition
PDE
Term
_____, a drug prescribed for erectile dysfunction is a potent inhibitor in the human _____ and in vascular and GI smooth muscle.
Definition
corpus cavernosum
Term
In the penis, ___ produces erection via a ___-dependent pathway, as the cGMP is degraded by ____, the vasodilatory signal attenuates and the erection subsides.
Definition
NO; cGMP; PGE5
Term
____ inhibits PDE5, delaying cGMP degradation and thus prolonging erection. It is highly selective for PDE5 over PDE3, a cAMP-specified PDE involved in the regulation of ______.
Definition
Sildenafil; cardiac contracility
Term
Inhibition of ___ increases the incidence of cardiac arrythmias and decreases long-term mortality in heart failure patients.
Definition
PDE3
Term
Sildenafil also inhibits, to a lesser extent, PDE6, which is localized to photoreceptors in the _____, and one of the side effects sometimes reported with Sildenafil use is a ________ tint in the patient's vision.
Definition
retina; blue-green
Term
Because PDE5 is present in _________, Sildenafil causes a mild, clinically insignificant, reduction in blood pressure due to ____, but more importantly, it greatly exacerbates the effects of nitrates and external NO donors such as _____, taken for angina, causing potentially fatal ______.
Definition
vascular smooth muscle; vasodilation; nitroglycerin; hypotension
Term
Sildenafil is contraindicated in patients using ____ in any form. In addition, it is metabolized by both the ___ and ____ pathways. Inhibition of these pathways by other drugs may increase the plasma concentration of Sildenafil, intensifying ______.
Definition
Nitrates; CYP2C9 and 3A4; side effects
Term
Although NO is essential in tumoricidal and bactericidal functions of ____, overproduction of NO (by NOSII) has been implicated in septic/cytokine-induced circulatory ____ in humans through the activation of _______.
Definition
macrophages; shock; guanylate cyclase
Term
Overproduction of NO is responsible for profound _____ in postoperative patients complicated by _________ infections that produce endotoxins; this hypotension is often refractory to treatment with conventional vasoconstriction drugs.
Definition
hypotension; bacterial
Term
Therapeutic intervention by ______ inhibitors is being investigated for treatment of septic shock, inflammatory diseases of the GI tract (such as pancreatitie and ulcerative colitis), and ____.
Definition
NOS; arthritis
Term
____ plays a critical role in maintaining a base vasotonus in hemodynamic regulation such that a decrease in the production of NO could result in hypertension, ________, or atherosclerosis
Definition
NOSIII; thrombosis
Term
Direct application of NO gas may be beneficial in the treatment of _________.
Definition
Pulmonary hypertension
Term
T/F: In selected patients, NO improved arterial oxygenation and increased pulmonary arterial hypertension.
Definition
False: DECREASED pulmonary arterial hypertension
Term
T/F: Inhales NO can reduce the need for extracorpeal membrane oxygenation in newborn patients with hypoxic respiratory failure, which was both expensive and invasive.
Definition
True
Term
T/F: Inhaled NO has been used to treate ARDS, inducing vasodilation, decreasing MPAP, and increasing cardiac index?
Definition
True
Term
When the gene for ___ has been knocked out in mice, the animals have distended stomachs due to constriction of the ____, which is relaxed via signaling by ____ (line 1) located in the neurons that innervate the myenteric plexus.
Definition
NOSI; pyloric sphincter; NOSI
Term
The NOSI-deficient mice are also resistant to _____ damage as a result of ischemic injury, suggesting involvement of NOSI, in the injurious process. Thus, specific inhibition or induction of the isoforms of ______ synthase is an ideal goal for therapeutic intervention.
Definition
brain; nitric-oxide
Term
____, more correctly called glyceryl trinitrate, was first synthsized by A. Sobrero ins 1847. It was extremely ___ and many fatal accidents occurred.
Definition
Nitroglycerin; explosive
Term
Alfred Nobel developed a procedure in 1846 to stabilize nitroglycerine by mixing it with _________ which became known as dynamite and the bases of the Nobel prizes.
Definition
Diatomaceous earth
Term
In 1867, Sir Thomas Lauder Brunton first reported the use of inhaled ____ in his patients with chest pains and in 1879, William Murrell published an article describing the use of the longer-lasting and more convenient compound nitroglycerin to better alleviate the pain of ______.
Definition
amyl nitrate; angina pectoris
Term
Nitroglycerin worked by dilating ________ of the heart, thus allowing more ____ of the tissue.
Definition
arteries; oxygenation
Term
Not until 1987, over a century after Murrell's publication that ______ gas released from nitroglycerin metabolism was postulated to be the active agent in the ____ of the coronary blood vessels. Even today the actual ____ of the NO release from nitroglycerin is unclear.
Definition
nitric-oxide; dilation; mechanism
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