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204. Which of the following would least likely benet
a patient in acute pulmonary edema due to
congestive heart failure?
A. Intravenous morphine
B. Digoxin
C. Oxygen
D. Rotating tourniquets
205. Hypothyroidism is a possible consequence of
prolonged therapy with:
A. Procainamide B. Mexiletine
C. Sotalol D. Amiodarone
206. Which of the following drug is used to reduce
the frequency of angina pectoris as well as to
terminate an acute attack?
A. Digoxin B. Furosemide
C. Enalapril D. Amrinone
207. Normal value of clotting time in humans is:
A. 3-4 minutes B. 8-9 minutes
C. 25-30 minutes D. Above 1 hr
208. Method used for recording blood pressure is:
A. Palpatory method
B. Oscillatory method
C. Auscultatory method
D. All of the above
209. The rst upword deection in ECG is:
A. T wave B. P wave
C. QRS wave D. ST wave
210. Which of the following is longest acting nitrate?
A. Glyceryl trinitrate
B. Ethyl tetranitrate
C. Octyl nitrite
D. Pentaerythritol tetranitrate
ANSWER KEY
1. D 2. B 3. A 4. A 5. D 6. C 7. A 8. B 9. B 10. C 11. D 12. B 13. A 14. D
15. B 16. B 17. B 18. C 19. D 20. D 21. B 22. C 23. D 24. A 25. A 26. D 27. C 28. C
29. D 30. C 31. C 32. B 33. D 34. D 35. B 36. D 37. A 38. D 39. A 40. B 41. B 42. D
43. B 44. D 45. B 46. B 47. B 48. A 49. A 50. C 51. B 52. D 53. B 54. B 55. B 56. C
57. B 58. A 59. B 60. C 61. D 62. C 63. A 64. D 65. D 66. C 67. D 68. B 69. B 70. C
71. D 72. D 73. B 74. C 75. B 76. A 77. C 78. A 79. A 80. C 81. D 82. A 83. D 84. B
85. C 86. D 87. A 88. D 89. A 90. C 91. C 92. A 93. B 94. D 95. A 96. C 97. D 98. D
99. D 100. C 101. B 102. A 103. C 104. B 105. C 106. D 107. C 108. D 109. D 110. D 111. A 112. D
113. B 114. C 115. C 116. A 117. D 118. D 119. D 120. C 121. C 122. B 123. C 124. D 125. D 126. B
127. A 128. C 129. D 130. A 131. D 132. C 133. C 134. A 135. C 136. D 137. B 138. C 139. B 140. B
141. B 142. B 143. C 144. D 145. B 146. C 147. C 148. C 149. B 150. B 151. A 152. D 153. A 154. C
155. C 156. C 157. B 158. C 159. B 160. D 161. A 162. D 163. D 164. C 165. D 166. D 167. B 168. C
169. B 170. D 171. B 172. A 173. C 174. D 175. C 176. B 177. A 178. D 179. B 180. C 181. D 182. B
183. C 184. C 185. A 186. D 187. B 188. D 189. D 190. C 191. C 192. C 193. B 194. C 195. A 196. B
197. D 198. C 199. A 200. A 201. A 202. B 203. D 204. D 205. D 206. A 207. A 208. D 209. B 210. D
Section 1 Pharmacology
49
4. Drugs Acting on Urinary System
URINARY SYSTEM
The kidneys filter unwanted substances from the blood
and produce urine to excrete them. There are three main
steps of urine formation:
Glomerular filtration,
Reabsorption, and
Secretion.
1. The glomerulus capsule filters water and other
substances from the bloodstream
z
Each kidney contains over 1 million tiny structures
called nephrons (functional unit of kidney).
z
Each nephron has a glomerulus, the site of blood
filtration. The glomerulus is a network of capillaries
surrounded by a cuplike structure, the glomerular
capsule (or Bowman’s capsule).
z
As blood flows through the glomerulus, blood pressure
pushes water and solutes from the capillaries into the
capsule through a filtration membrane.
z
This glomerular filtration begins the urine formation
process.
2. The filtration membrane keeps blood cells and large
proteins in the bloodstream
z
Inside the glomerulus, blood pressure pushes fluid
from capillaries into the glomerular capsule through
a specialized layer of cells.
z
This layer, the filtration membrane, allows water
and small solutes to pass but blocks blood cells and
large proteins. Those components remain in the
bloodstream.
z
The filtrate (the fluid that has passed through the
membrane) flows from the glomerular capsule further
into the nephron.
3. Reabsorption moves nutrients and water back into the
bloodstream
z
The glomerulus filters water and small solutes out of
the bloodstream.
z
The resulting filtrate contains waste, but also other
substances the body needs: essential ions, glucose,
amino acids, and smaller proteins.
z
When the filtrate exits the glomerulus, it flows into
a duct in the nephron called the renal tubule. As
it moves, the needed substances and some water
are reabsorbed through the tube wall into adjacent
capillaries.
z
This reabsorption of vital nutrients from the filtrate is
the second step in urine creation.
4. Waste ions and hydrogen ions secreted from the blood
complete the formation of urine
z
The filtrate absorbed in the glomerulus flows through
the renal tubule, where nutrients and water are
reabsorbed into capillaries.
z
At the same time, waste ions and hydrogen ions pass
from the capillaries into the renal tubule. This process
is called secretion.
z
The secreted ions combine with the remaining filtrate
and become urine. The urine flows out of the nephron
tubule into a collecting duct. It passes out of the kidney
through the renal pelvis, into the ureter, and down to
the bladder.
Glomerular Filtration Rate (GFR)
The volume of filtrate formed by both kidneys per minute
is termed the glomerular ltration rate (GFR).
180 L/day in men and 150 L/day in women.
Section 1 Pharmacology
50
Fig. 4.1: Nephron
GFR affected by the hydrostatic pressure, colloid osmotic
pressure and on either side of the capillary membrane
of the glomerulus.
Net Filtration Pressure (NFP)
NFP determines filtration rates through the kidney.
NFP = Glomerular blood hydrostatic pressure (GBHP)
– [capsular hydrostatic pressure (CHP) + blood colloid
osmotic pressure (BCOP)]
NFP = GBHP – [CHP + BCOP]
NFP = 55 – [15 + 30]
= 10 mm Hg
Symptoms of kidney dysfunctioning: weakness, lethargy,
difficulty in breath, edema, anemia, acidosis/ alkalosis,
arrhythmias, blood in urine, loss of appetite, fatigue,
frequent urination, and oliguria.
Diuretics
Diuretics are agents that increase the volume of urine
as well as solutes dissolved in it, by decreasing the
reabsorption of sodium at different sites in the nephron.
Diuretics thus increase the volume of both urine and often
change its pH as well as the ionic composition of urine
and blood. Their efficacy in sodium secretion varies from
2% to 20% in case of potassium sparing diuretics and loop
diuretics respectively.
Major clinical use of diuretics is in managing disorders
involving abnormal fluid retention (edema) or treating
hypertension and glaucoma.
Classifications
There are two basis of classification:
1. According to site of action (Fig. 4.2)
2. According to efficacy (Fig. 4.3)
Fig. 4.2
Fig. 4.3
Classification of Diuretics
Classification
1. High efficacy or loop diuretic (inhibitors of sodium and
potassium chloride transport)
z
Sulphonyl derivative: Furosemide
z
Phenoxy acetic acid: Ethacrynic Acid
z
Organomercurials: Mersalyl
2. Medium efficacy (inhibitors of sodium chloride
symport)
z
Thiazides: Hydrochlorothiazide, clopamide
z
Thiazides Like: Chlorothiazide and indapamide,
xipamide.
3. Weak or adjunctive diuretics
z
Carbonic anhydrase inhibitor: Acetazolamide
z
Potassium sparing: Spironolactone, triamterene,
amiloride
z
Xanthine: Theophylline.
z
Osmotic diuretics: Mannitol, glycerol
z
Acidifying or alkalinizing salt: NH4Cl, potassium
citrate.
Side effect
1. Hypokalaemia
z
It causes muscles cramps, fatigue, cardiac arrhythmia.
z
It is more common with high efficacy then with thiazide.
Section 1 Pharmacology
51
z
It is treated by high dietary potassium ion intake.
z
Supplements of kcl.
z
Concurrent use of potassium ion and sparing diuretics.
2. Dilutional hyponatremia
z
kidney tends to retain.
z
Though it is unable to retain salt due to diuretics
so gets diluted and hyponatremia occurs and
edemainspite natriuresis.
3. Acute saline depletion
z
It is due to dehydration and decrease in blood
pressure.
4. Magnesium depletion
z
So increased risk of ventricular arrhythmia, especially
after myocardial infarction.
5. Hypercalcemia
z
It occurs with relatives while hypocalcaemia is with
loop diuretics.
6. Hyperglycaemia and hyperlipidaemia
z
It is because K+ depletion interfere conversion of
proinsulin to insulin.
7. Hyperuricaemia
z
More common with thiazide.
8. Not used in toxemia of pregnancy
z
As in it blood volume is low despite of edema.
9. GIT and CNS disturbance
z
Cause nausea, vomiting, diarrhoea may occur with
any drug.
10. Hearing loss
z
It occurs only with loop diuretic specially with
electronics acid.
11. Allergic manifestation
z
Rashes, photosensitivity especially in-patient
hypersensitivity to sulfonamide.
Uses:
1. Edema: It is used in edema in any of the cases—cardiac,
hepatic, renal hypoproteinemia.
2. Acute pulmonary edema: It is an acute left ventricle
failure following decrease in blood volume and venous
return responsible for improvement.
3. Cerebral edema: It is due to road traffic accident,
meningitis, brain tumor, glaucoma, migraine. Osmotic
diuretics is preferred.
4. Forced diuresis: It is done in hypnotic or other poisoning.
5. Hypertension: Thiazide are given.
6. Along with blood transfusion in severe anaemia to
prevent vascular overload.
7. Hypercalcemia and renal stone— loop diuretics are
preferred.
8. Increase intracranial or intra ocular pressure (acute
conjunctive glaucoma (closed), headinjury) by osmotic
action it encourages the movement of water from brain
parenchyma CSF and aqueous humorous.
High ceiling (loop diuretics)
It is a member of loop diuretics. Site of action is thick
Section 1 Pharmacology
(medullary part) of ascending loop of Henle. The intensity
of diuresis produced by maximum dose is high, hence they
52
are called high ceiling diuretics.
Mechanism of action
At molecular level, loop diuretics bind with the site for
Cl– ions of uniport, symport or cotransport system and
thus blocking the working of the symporter they produce
diuresis.
Furosemide:
High ceiling (loop diuretics)
Major site of action is thick ascending loop of Henley
Inhibit Na+ –K+ –2Cl– co-transport
Its action is not dependent of acid base balance
IV causes sudden increase in systemic venous capacitance
Increases ca as well as mg excretion
Abolishes the corticomedullary osmotic gradient in the
kidney
Increase blood uric acid level
Highly bound to plasma proteins
Therapeutic uses
1. Drugs of choice for reducing the acute pulmonary edema
of heart failure. Because of their rapid onset of action,
particularly when given intravenously.
2. They are useful in emergency situations such as acute
pulmonary edema which calls for a rapid intense
diuresis.
3. They are also useful in treating hypercalcemia because
they stimulate tubular calcium excretion.
4. They also are useful in the treatment of hyperkalemia.
Bumetanide
40 times more potent as compared to furosemide
Like furosemide
Thiazide and related diuretics
Inhibition of Na+ Cl– symport (12 membrane spanning
domains that binds thiazide but not Furosemide or any
other class drugs)
Action given on early distal convoluted tubule
Urinary K excretion increased
Tend to reduce GFR
They decrease renal Ca excretion and increase Mg
excretion
Slow developing fall in BP
Elevation of blood sugar in some cases
They induce diuresis in acidosis as well as alkalosis
Metolazone
Common loop diuretic
Useful in severe renal failure
Indapamide
Has antihypertensive effects
Carbonic anhydrase inhibitors
Acetazolamide
Derivative of sulfonamide
Reversibily inhibit CAse in PCT
Self-limiting diuretic
Current use of acetazolamide in glaucoma
Amiloride
Potassium sparing weak natriuretics.
Potassium Sparing Diuretics
Spironolactone
Steroid
Aldosterone antagonist (aldosterone produces its effect
by increasing membrane permeability to potassium)
Itself not an efficacious diuretic prefers used as an
adjuvant to other diuretics
Potassium sparing weak natriuretics.
Osmotic diuretics
They can lower intraocular pressure
Table 4.1: Uses of diuretics
Medical conditions Diuretics Clinical Uses
Glaucoma CA inhibitor— Acetazolamide Formation of aqueous humor
Ascites Aldosterone antagonist—Spironolactone Inhibition of aldosterone metabolism
Nephrotic syndrome Loop diuretic—Furosemide Requires immediate relief from huge edema
Pulmonary edema Loop diuretic—Furosemide Free of respiratory embarrassment
Edema due to starvation Loop diuretic—Furosemide Severe form of edema
Long-standing hypertension Thiazides Vasodilatation
Hypertensive crisis Loop diuretic—Furosemide To acquire immediate effect
Head injury/increased
intracranial pressure
Diabetes insipidus Thiazides Decrease serum potassium
Osmotic diuretic—Mannitol Decrease intracranial pressure
Mannitol
Given in large quantities
Increase osmolarity of plasma and tubular fluid
Inhibit transport processes in the thick ascending loop
of henle
Increase extracellular fluid volume
Increase renal blood flow
It is contraindicated in acute left ventricular failure
It is not used to treat cardiac or hepatic or renal edema
Parenteral furosemide is an alternative diuretic to
mannitol in case of cerebral edema
MULTIPLE CHOICE QUESTIONS
1. Secretion of K+ in nephron depends on:
A.
Intracellular K+ content
B. Unabsorbed Na+ amount presented to the distal
segment
C. Level of Aldosterone
D. All
2. Example of diuretic which is orally active, work
well in acidosis as well as alkalosis condition,
causes diuresis even in case of renal failure and has
additional carbonic anhydrase suppression action:
A.
Furosemide B. Benzthiazide
C. Indapamide D. Mannitol
3. Furosemide acts by inhibiting the following in the
renal tubular cell:
A.
Na+–K+–2Cl– cotransporter
B. Na+–Cl– symporter
C. Na+–H+ antiporter
D. Na+ K+ ATPase
4. The following diuretic suppress the corticomedullary osmotic gradient in the kidney:
A.
Acetazolamide
B. Furosemide
C. Hydrochlorothiazide
D. Spironolactone
5. In the condition of acute left ventricular failure,
dyspnoea rapidly diminishes by the use of
intravenous furosemide by following mechanism:
Bronchodilatation
A.
B. Causing rapid diuresis and reducing circulating
blood volume
C. Enhancing venous capacitance and reducing
cardiac preload.
D. Stimulating left ventricular contractility
6. Name that substance which has a lower
concertation at the starting proximal tubule and
more concentration at the end of the proximal
tubule?
Glucose B. Creatinine
A.
C. Sodium D. Bicarbonate
7. Parenteral furosemide is an alternative diuretic to
mannitol in the following condition:
Pulmonary edema B. Cirrhotic edema
A.
C. Cerebral edema D. Cardiac edema
8. Thiazide diuretics and furosemide have equal
antagonistic effect on the total renal excretion of
the following substance:
Uric acid B. Calcium
A.
C. Magnesium D. Bicarbonate
Section 1 Pharmacology
53
9. Choose one of following diuretic which is similar
in efcacy and pattern of electrolyte excretion to
furosemide, but is 40 times more potent dose to
dose:
Piretanide B. Bumetanide
A.
C. Xipamide D. Metolazone
10. When a person is dehydrated, hypotonic uid will
be found in the:
Glomerular filtrate B. Proximal tubule
A.
C. Loop of Henle D. Collecting duct
11. Ethacrynic acid is a high ceiling diuretic, but it is
generally not recommended due to:
It is more ototoxic
A.
B. It causes diarrhoea and gut bleeding
C. Its response increases steeply over a narrow
dose range
D. All the above
12. The Na+–Cl– symport in the early distal convoluted
tubule of the kidney is inhibited by:
Thiazides B. Metolazone
A.
C. Xipamide D. All the above
13. The following diuretic reduces positive free water
clearance but does not affect negative free water
clearance:
Hydroflumethiazide
A.
B. Furosemide
C. Ethacrynic acid
D. Mannitol
14. Choose the correct statement about thiazide
diuretics:
Their site of action is proximal convoluted
A.
tubule
B. They are uricosuric
C. They enhance corticomedullary osmotic
gradient
D. They induce diuresis in acidosis as well as
alkalosis
15. Thiazide diuretics enhance K+ elimination in urine
primarily by:
Inhibiting proximal tubular K+ reabsorption
A.
B. Inhibiting Na+ K+-2Cl-cotransport in the
ascending limb of loop of Henle
C. Increasing the availability of Na+ in the distal
tubular fluid to exchange with interstitial K
D. Potentiating the action of aldosterone
16. The primary action site of thiazide diuretics is:
A. Proximal convoluted tubule
B. Ascending limb of loop of Henle
C. Cortical diluting segment
D. Collecting ducts
17. The most important reason for the thiazides being
only moderately efcacious diuretics is:
About 9/10th of glomerular filtrate is reabsorbed
Section 1 Pharmacology
54
A.
proximal to their site of action
B. Compensatory increase in reabsorption at sites
not affected by these drugs
C. They decrease glomerular filtration
D. They have relatively flat dose response curve
18. Individual drugs of thiazide and related class of
diuretics differ markedly from each other in the
following respect?
Diuretic efficacy
A.
B. Diuretic potency
C. Side effects
D. Propensity to cause hyperkalemia
19. Combined tablets of thiazide or high ceiling
diuretics with potassium chloride are not
recommended because:
Potassium absorbed while diuresis is occur-ring
A.
is largely excreted out
B. Potassium administered concurrently
diminishes the diuretic action
C. Potassium chloride in tablet formulation is
likely to cause gut ulceration
D. Both ‘A’ and ‘C’ are correct
20. Intravenous saline infusion is the treatment
of choice for the following complication(s) of
vigorous furosemide therapy:
Dilutional hyponatremia
A.
B. Acute saline depletion
C. Hypokalemia
D. All the above
21. Long-term thiazide therapy can cause
hyperglycaemia by:
Reducing insulin release
A.
B. Interfering with glucose utilization in tissues
C. Increasing sympathetic activity
D. Increasing corticosteroid secretion
22. In addition to counteracting potassium loss,
triamterene also opposes the following
consequence of thiazide/furosemide therapy:
Hyperuricaemia
A.
B. Rise in plasma LDL-cholesterol
C. Magnesium loss
E. Both ‘A’ and ‘C’ are correct
23. A patient of congestive heart failure treated with
furosemide and digoxin also has urinary tract
infection. Which of the following antimicrobials
+
should be avoided in this case
Ampicillin
A.
B. Gentamicin
C. Norfloxacin
D. Cotrimoxazole
24. Nonsteroidal anti-inammatory drugs reduce the
diuretic action of furosemide by:
Preventing prostaglandin mediated intra-renal
A.
haemodynamic actions
B. Blocking the action in ascending limb of loop
of Henle.
C. Enhancing salt and water reabsorption in distal
tubule
D. Increasing aldosterone secretion
25. When furosamide used for long term it is
respansiveness decrease. Choose most suitable
measure to overcome this:
A.
Addition of parenteral form of furosemide
B. Addition of a thiazide diuretic in drug regimen
C. Addition of acetazolamide in drug regimen
D. Both ‘A’ and ‘B’ are correct
26. At equinatriuretic doses which diuretic causes the
maximum K+ loss:
A. Furosemide B. Chlorothiazide
C. Spiranolactone D. Amiloride
27. Which of the following has a ‘self-limiting
diuretic’ action:
A.
Butanamide B. Spironolactone
C. Furesamide D. Acetazolamide
28. from which part of nephron Amino acids are
almost completely reabsorbed in blood circulation
from the glomerular filtrate through active
transport in the:
A.
Proximal tubule B. Loop of Henle
C. Distal tubule D. Renal pelvis
29. Select one of the drug which itself do not has
an efcacious diuretic action, used only as an
adjuvant/corrective to other diuretics:
A.
Acetazolamide B. Metolazone
C. Spironolactone D. Indapamide
30. Spironolactone can be usefully combined with the
following diuretics except:
A. Furosemide
B. Amiloride
C. Hydrochlorothiazide
D. Chlorthalidone
31. The current therapeutic indication of acetazolamide is:
A. Congestive heart failure
B. Renal insufficiency
C. Cirrhosis of liver
D. Glaucoma
32. A patient with liver cirrhosis along with ascites
was treated with hydrochlorothiazide 50 mg twice
daily. He responded initially, but over a couple of
months the diuretic action gradually diminished
and ascites again appeared. Select the measure to
reinduce diuresis:
A.
Increase hydrochlorothiazide dose to 100 mg
twice daily
B. Add acetazolamide 250 mg twice daily
C. Add spironolactone 50 mg thrice daily
D. Substitute hydrochlorothiazide by
spironolactone 50 mg 6 hourly
33. Aldosterone increases Na+ reabsorption and K+
excretion in the renal collecting duct cells by:
Inducing synthesis of Na+–K+–ATPase
A.
B. Inducing synthesis of amiloride sensitive Na+
channels
C. Translocating Na+ channels from cytosolic site
to luminal membrane
D. All the above
34. Which of the following diuretic drug produces
gynaecomastia, hirsutism and menstrual
disturbance as a side effect on long-term use:
A.
Triamterene B. Spironolactone
C. Bumetanide D. Torsemide
35. Amiloride inhibits K+ excretion in the distal
tubules and collecting ducts by blocking:
A. Electrogenic K+ channels
B. Electrogenic Na+ channels
C. Nonelectrogenic Na+–Cl– symport
D. H+–K+–ATPase
36. Which of the following is a potassium retaining
diuretic:
A. Triamterene B. Trimethoprim
C. Tizanidine D. Trimetazidine
37. In which aspect triamterene differs from
spironolactone:
A. Greater natriuretic action
B. K+ retaining action is not dependent on presence
of aldosterone
C. Acts from the luminal membrane side of the
distal tubular cells
D. Both ‘B’ and ‘C’ are correct
38. Choose the correct statement about amiloride:
A. It antagonizes the action of aldosterone
B. It can be used to treat lithium induced diabetes
insipidus
C. It increases calcium loss in urine
D. It is dose to dose less potent than triamterene
39. Amiloride has the following effect on urinary
cation excretion:
Decreases both K+ and H+ ion excretion
A.
B. Decreases K+ excretion but increases H+ ion
excretion
C. Increases K+ but decreases Na+ excretion
D. Decreases both Na+ and K+ excretion
40. Use of potassium sparing diuretics in patients
receiving the following drug needs close monitoring:
A. Furosemide B. Hydrochlorothiazide
C. Captopril D. Verapamil
41. Choose the correct statement about osmotic
diuretics:
A. They are large molecular weight substances
which form colloidal solution
B. Their primary site of action is collecting ducts
in the kidney
C. They increase water excretion without increasing
salt excretion
D. They can lower intraocular pressure
42. The following is true of mannitol except:
A. It inhibits solute reabsorption in the thick
ascending limb of loop of Henle
B. It is contraindicated in patients with increased
intracranial tension
C. It is contraindicated in acute left ventricular failure
D. It is not used to treat cardiac or hepatic or renal
edema
Section 1 Pharmacology
55
43. Example of selective vasopressin V2 receptor
agonist:
A. Histidine vasopressin
B. Desmopressin
C. Lypessin
D. All
44. The primary mechanism by which antidiuretic
hormone reduces urine volume is:
A. Decrease in glomerular filtration rate
B. Decreased renal blood flow
C. Decreased water permeability of descending
limb of loop of Henle
D. Increased water permeability of collecting duct
cells
45. The vasopressin action(s) mediated by V2
receptors include(s):
A. Increased water permeability of collecting duct
cells
B. Increased urea permeability of collecting duct
cells
C. Vasoconstriction
D. Both 'A' and 'B'
46. The kidney excreted a concentrated urine this
condition will increases if
A. The permeability of the proximal convoluted
tubule decreases for water molecules
B. The rate of blood circulation through the
medulla diminished
C. The functionality of the Na-K pump decreases
in the area of loop of Henley
D. None
47. Desmopressin is preferred over arginine
vasopressin in the treatment of diabetes insipidus
for the following reasons except:
A. It is a more potent antidiuretic
B. It is a selective vasopressin V1 receptor agonist
C. It has little vasoconstrictor activity
D. It is longer acting
48. Select the action of vasopressin exerted through
the V1 subtype receptors:
A. Release of coagulation factor VIII and von
Willebrands factor from vascular endothelium
B. Increased peristalsis of gut
C. Dilatation of blood vessels
D. Increased water permeability of renal collecting
ducts
49. The following tissue is most sensitive to
vasopressin:
A. Renal collecting ducts
B. Intestinal smooth muscle
C. Vascular smooth muscle
D. Uterus
50. Desmopressin reduces urine volume in:
A. Neurogenic diabetes insipidus
Section 1 Pharmacology
56
B. Nephrogenic diabetes insipidus
C. Both neurogenic as well as nephrogenic diabetes
insipidus
D. Both A and B correct
51. Choose the correct statement(s) about terlipressin:
A. It is a prodrug
B. It is recommended for preventing bleeding from
esophageal varices
C. It is preferred for controlling bleeding in von
Willebrand's disease
D. Both 'A' and 'B' are correct
52. The following is true of desmopressin except:
A. It is nonselective V1 and V2 receptor agonist
B. It is more potent and longer acting than arginine
vasopressin (AVP)
C. It is preferred over AVP for treatment of
diabetes insipidus
D. It can be administered orally
53. Indications of desmopressin include the following
except:
A. Neurogenic diabetes insipidus
B. Nephrogenic diabetes insipidus
C. Bedwetting in children
D. Bleeding due to haemophilia
54. Arginine vasopressin is preferred over
desmopressin in the following condition:
A. Diabetes insipidus
B. Bedwetting in children
C. Bleeding esophageal varices
D. Bleeding in haemophilia
55. Which of the following drug is orally active and
decreasing urine volume in both pituitary origin
as well as:
A. Vasopressin B. Hydrochlorothiazide
C. Chlorpropamide D. Carbamazepine
56. If concentration potassium increases in plasma it
will increase
A. Release of renin
B. Secretion of aldosterone
C. Secretion of ADH
D. Release of natriuretic hormone
57. In nephron of human kidney H+ ion secreted by
the proximal convoluted tubule is associated with:
A. Elimination of K+ ion
B. Excretion of H+ ion
C. Reabsorption of Cl ++ ion
D. Reabsorption of HCO3- ion
58. From the following which factor having least
role in maintaining the synthesis and secretion
of aldosterone?
A. Renin
B. Angiotensin II
C. Amount of K+ in plasma
D. Adrenocorticotropic hormone
59. Most of the filtered glucose in nephron is
reabsorbed from ……………………
A. Proximal convoluted tubule
B. loop of Henle
C. Distal convoluted tubule
D. All of the above
60. Ammonia is act as an efcient urinary buffer due
to
A.
In kidney its production decrease during
chronic acidosis
B. The walls of the renal tubules are permeable to
ammonia
C. The walls of the renal tubules are impermeable
to NH
4
D. None
61. Potassium excretion by the kidney will decreases
if:
A.
Distal tubular flow rate increases
B. Circulating aldosterone level enhanced
C. Potassium dietary intake increases
D. Sodium reabsorption decreases by the distal
nephron
62. In the presence of ADH, the distal nephron is least
permeable to:
A.
Water
B. Ammonia
C. Urea
D. Sodium
63. Choose one correct statement about aldosterone
A. It produces its effect by alleviating the level of
c-AMP
B. It acts by enhancing the membrane permeability
to potassium
C. It causes an increased reabsorption of hydrogen
ion
D. Its secretion is dependent on increase in blood
pressure
64. Function of antidiuretic hormone on kidney is:
A. To Increase the permeability of the distal
convoluted tubule towards water.
B. To Increase the excretion of sodium ion
C. To Increase the water excretion
D. To dilate renal artery
65. One of the following factor increases glomerular
ltration rate if
A.
Circulating blood volume increase
B. The afferent arteriolar resistance increases
C. The efferent arteriolar resistance decreases
D. The plasma protein concentration decreases
66. ……………….is denes as the volume of plasma
required each minute to supply a substance at the
rate at which it is excreted in the urine.
A.
Diffusion constant B. Clearance
C. Extraction ratio D. All
67. Mark the correct answer regarding proximal
convoluted tubules:
A.
K+ is secreted in exchange with the Na
+
B. Glucose, amino acids & proteins are completely
reabsorbed in blood
C. Parathormone increase phosphate reabsorption
D. All are correct
68. The secretion site for organic ions like creatinine
in kidney is:
A.
Proximal convoluted tubule
B. Ascending Loop of Henle
C. Distal convoluted tubule
D. Final collecting duct
69. Reabsorption of Na+:
A.
Occurs with the association of Cl- & HCO
–
3
B. Occurs only in PT
C. Is regulated by parathormone hormone
D. Is a kind of passive
70. Diamox causes:
A. Water diuresis
B. Hypokalaemia
C. Alkalosis
D. All the above
71. K+ excretion is inuenced mainly by:
A.
Aldosterone
B. Amount of Na+ reached to tubules
C. Amount of tubular secretion of H
+
D. All
72. More hydrogen is secreted in:
A. Alkalosis
B. Administration of diamox
C. Hypokalaemia
D. Hyperventilation
73. All of the following determined plasma osmolarity
except:
A.
Sodium
B. Hemoglobin
C. Chloride
D. Albumin
74. The hypothalamus will affect the release of ADH
in response to all the following stimuli except:
A.
Dehydration
B. Severe hemorrhage
C. Decreased blood osmolarity
D. Nicotine
75. All of the following condition increases urinary
volume except:
A.
Diabetes insipidus
B. Diabetes mellitus
C. Sympathetic stimulation
D. None
76. All are significant buffers for hydrogen ions
generated in the body from anaerobic metabolism
except:
A.
Extracellular bicarbonate
B. Plasma proteins
C. Plasma lactate
D. Intracellular proteins
Section 1 Pharmacology
57
77. All statements are true about the H+ secreted into
the lumen of the distal nephron except:
A.
Can combine with NH
B. Can combine with HCO
+
4
3
C. Can combine with HPO
D. Is secreted by an H+- ATPase pump
78. The glomerular ltration barrier is composed of
all the following except:
A.
Fenestrated capillary endothelium.
B. Macula densa.
C. Basement membrane.
D. Podocytes.
79. All of the following statements are true about
proximal convoluted tubules except:
A.
It responsible for reabsorption of most of the
Na+ ions
B. It responsible for reabsorption of most of the K
ions
C. Ions in glomerular filtrate
D. Contains JGCS which is responsible for the
secretion of renin
ANSWER KEY
1. D 2. A 3. A 4. B 5. C 6. B 7. C 8. B 9. B 10. C 11. D 12. D 13. A 14. D
15. C 16. C 17. A 18. B 19. D 20. B 21. A 22. C 23. B 24. A 25. B 26. C 27. D 28. A
29. C 30. B 31. D 32. C 33. D 34. B 35. B 36. A 37. D 38. B 39. A 40. C 41. D 42. B
43. B 44. D 45. D 46. B 47. B 48. B 49. A 50. A 51. D 52. A 53. B 54. C 55. B 56. B
57. D 58. D 59. A 60. C 61. D 62. C 63. B 64. A 65. D 66. B 67. B 68. A 69. A 70. B
71. A 72. C 73. B 74. D 75. C 76. C 77. A 78. B 79. D
+
5. Drugs Acting on Respiratory System
Cough is a protective reflex, its purpose being expulsion
of respiratory secretions and foreign particles from air
passages.
It occurs due to stimulation of mechano- or
chemoreceptors in throat and respiratory passages or
stretch receptors in the lungs.
DEMULCENTS AND EXPECTORANTS
Pharyngeal demulcents soothe the throat and reduce
afferent impulses from the inflamed/ irritated pharyngeal
mucosa, thus provide symptomatic relief in dry cough
arising from throat.
Expectorants (mucokinetics) are drugs believed to
increase bronchial secretion or reduce its viscosity,
facilitating its removal by coughing. Sodium and potassium
citrate are considered to increase bronchial secretion by salt
action. Potassium iodide is secreted by bronchial glands
and can irritate the airway mucosa.
Drugs for cough
1. Pharyngeal demulcents—lozenges, cough drops,
glycerine liquorice.
2. Expectorant (mucokinetic)—increase bronchial secretion
or reduce its viscosity and facilitate its by coughing.
z
Directly acting—sodium and potassium citrate and
potassium iodide
Section 1 Pharmacology
z
Reflectly acting—potassium Iodide
z
58
Mucolytic agent—acetylcysteine bromhexine
carbocysteine
3. Antitussive (cough centre suppressant)
z
Opioid—codeine, pholocodeine, morphine
z
Non-opioid—noscapine, dextromethorphan
z
Antihistamine—chlorpheniramine, diphenhydramine,
promethazine
Antitussive (reduce cough)
These are drugs that act in the CNS to raise the threshold of
cough center or act peripherally in the respiratory tract to
reduce tussal impulses, or both these actions. Because they
aim to control rather than eliminate cough, antitussive
drugs should be used only for dry nonproductive cough
or if it is unduly tiring, disturbs sleep or is hazardous
(hernia, piles, cardiac disease, ocular surgery).
Opioid antitussives
Morphine and its congeners are the most effective
antitussives, but morphine is not suitable for treating
cough, because of its strong addicting and respiratory
depressant property.
Codeine
An opium alkaloid but less potent than morphine.
More selective for cough centre.
Suppress cough for 6 hours.
It acts through opioid receptor in brain, but constipation
is main drawback.
At higher dose respiratory depression and drowsiness
occur.
It is contraindicated in asthmatic and in patient which
is decrease respiratory reserve