Which of the following best describes the mechanism of action of scopolamine ? (a) Irreversible antagonist at nicotinic receptors (b) Irreversible antagonist at muscarinic receptors (c) Physiologic antagonist at muscarinic receptors (d) Reversible antagonist at muscarinic receptors (e) Reversible antagonist at nicotinic receptors

Which of the following best describes the mechanism of action of scopolamine ? (a) Irreversible antagonist at nicotinic receptors (b) Irreversible antagonist at muscarinic receptors (c) Physiologic antagonist at muscarinic receptors (d) Reversible antagonist at muscarinic receptors (e) Reversible antagonist at nicotinic receptors
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Last Answer : Ans: C

The cardiac muscarinic receptors (a) Are of the M1 subtype (b) Are of the M2 subtype (c) Are selectively blocked by pirenzepine (d) Function through the PIP2 ? IP3/DAG pathway

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Muscarinic cholinergic receptors (a) Are located only on parasympathetically innervated effector cells (b) Mediate responses by opening an instrinsic Na+ ion channel (c) Are present on vascular endothelium which has no cholinergic nerve supply (d) Predominate in the autonomic ganglia

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Last Answer : Ans: C

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Last Answer : Ans: D

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Last Answer : Ans: B

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Last Answer : Ans: C

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Last Answer : C. It has additional direct agonistic action on nicotinic receptors at the muscle end plate

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Description : Neostigmine is preferred over physostigmine for treating myasthenia gravis because: A. It is better absorbed orally B. It has longer duration of action C. It has additional direct agonistic action on nicotinic receptors at the muscle end plate D. It penetrates blood-brain barrier

Last Answer : C. It has additional direct agonistic action on nicotinic receptors at the muscle end plate

Propranolol does not block the following action of adrenaline (a) Bronchodilation (b) Lipolysis (c) Muscle tremor (d) Mydriasis

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Last Answer : Ans: D

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Description : Ephedrine is similar to adrenaline in the following feature (a) Potency (b) Inability to penetrate blood-brain barrier (c) Duration of action (d) Producing both a and ß adrenergic effects

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Which of the following mydriatics has the fastest and briefest action ? (a) Atropine (b) Homatropine (c) Tropicamide (d) Cyclopentolate

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Last Answer : Ans: C

Glycopyrrolate is the preferred antimuscannic drug for use before and during surgery because (a) It is potent and fast acting (b) It has no central action (c) It has antisecretory and vagolytic actions (d) All of the above

Description : Glycopyrrolate is the preferred antimuscannic drug for use before and during surgery because (a) It is potent and fast acting (b) It has no central action (c) It has antisecretory and vagolytic actions (d) All of the above

Last Answer : Ans: D

Action of norepinephrine and epinephrine are terminated by (a) Reuptake into nerve terminal (b) Dilution by diffusion and uptake at extraneuronal site (c) Metabolic transformation (d) All of the above

Description : Action of norepinephrine and epinephrine are terminated by (a) Reuptake into nerve terminal (b) Dilution by diffusion and uptake at extraneuronal site (c) Metabolic transformation (d) All of the above

Last Answer : Ans: D

The following are true about the muscarinic receptors: a. they are found at the postganglionic parasympathetic synapses b. they can be selectively blocked by atropine c. M1 muscarinic receptors are found in the brain d. all above

Description : The following are true about the muscarinic receptors: a. they are found at the postganglionic parasympathetic synapses b. they can be selectively blocked by atropine c. M1 muscarinic receptors are found in the brain d. all above

Last Answer : all above

Activation of the following type of receptors present on myenteric neurones by metoclopramide is primarily responsible for enhanced acetylcholine release improving gastric motility: A. Muscarinic M1 B. Serotonergic 5-HT3 C. Serotonergic 5-HT4 D. Dopaminergic D2

Description : Activation of the following type of receptors present on myenteric neurones by metoclopramide is primarily responsible for enhanced acetylcholine release improving gastric motility: A. Muscarinic M1 B. Serotonergic 5-HT3 C. Serotonergic 5-HT4 D. Dopaminergic D2

Last Answer : C. Serotonergic 5-HT4

Initial bradycardia caused by intramuscular injection of atropine is believed to be caused by: A. Stimulation of medullary vagal centre B. Stimulation of vagal ganglia C. Blockade of M2 receptors on SA nodal cells D. Blockade of muscarinic autoreceptors on vagal nerve endings

Description : Initial bradycardia caused by intramuscular injection of atropine is believed to be caused by: A. Stimulation of medullary vagal centre B. Stimulation of vagal ganglia C. Blockade of M2 receptors on SA nodal cells D. Blockade of muscarinic autoreceptors on vagal nerve endings

Last Answer : D. Blockade of muscarinic autoreceptors on vagal nerve endings

The cardiac muscarinic receptors: A. Are of the M1 subtype B. Are of the M2 subtype C. Are selectively blocked by pirenzepine D. Function through the PIP2 → IP3/DAG pathway

Description : The cardiac muscarinic receptors: A. Are of the M1 subtype B. Are of the M2 subtype C. Are selectively blocked by pirenzepine D. Function through the PIP2 → IP3/DAG pathway

Last Answer : B. Are of the M2 subtype

Muscarinic cholinergic receptors: A. Are located only on parasympathetically innervated effector cells B. Mediate responses by opening an intrinsic Na+ ion channel C. Are present on vascular endothelium which has no cholinergic nerve supply D. Predominate in the autonomic ganglia

Description : Muscarinic cholinergic receptors: A. Are located only on parasympathetically innervated effector cells B. Mediate responses by opening an intrinsic Na+ ion channel C. Are present on vascular endothelium which has no cholinergic nerve supply D. Predominate in the autonomic ganglia

Last Answer : C. Are present on vascular endothelium which has no cholinergic nerve supply

Initial bradycardia caused by intramuscular injection of atropine is believed to be caused by: A. Stimulation of medullary vagal centre B. Stimulation of vagal ganglia C. Blockade of M2 receptors on SA nodal cells D. Blockade of muscarinic autoreceptors on vagal nerve endings

Description : Initial bradycardia caused by intramuscular injection of atropine is believed to be caused by: A. Stimulation of medullary vagal centre B. Stimulation of vagal ganglia C. Blockade of M2 receptors on SA nodal cells D. Blockade of muscarinic autoreceptors on vagal nerve endings

Last Answer : D. Blockade of muscarinic autoreceptors on vagal nerve endings

The cardiac muscarinic receptors: A. Are of the M1 subtype B. Are of the M2 subtype C. Are selectively blocked by pirenzepine D. Function through the PIP2 → IP3/DAG pathway

Description : The cardiac muscarinic receptors: A. Are of the M1 subtype B. Are of the M2 subtype C. Are selectively blocked by pirenzepine D. Function through the PIP2 → IP3/DAG pathway

Last Answer : B. Are of the M2 subtype

Muscarinic cholinergic receptors: A. Are located only on parasympathetically innervated effector cells B. Mediate responses by opening an intrinsic Na+ ion channel C. Are present on vascular endothelium which has no cholinergic nerve supply D. Predominate in the autonomic ganglia

Description : Muscarinic cholinergic receptors: A. Are located only on parasympathetically innervated effector cells B. Mediate responses by opening an intrinsic Na+ ion channel C. Are present on vascular endothelium which has no cholinergic nerve supply D. Predominate in the autonomic ganglia

Last Answer : C. Are present on vascular endothelium which has no cholinergic nerve supply

Drugs that block the a receptor on effector cells at adrenergic nerve endings (a) Antagonize the effects of isoproterenol on the heart rate (b) Antagonize some of the effects of epinephrine on the blood pressure (c) Antagonize the effects of epinephrine on adenylyl cyclase (d) Cause mydriasis (e) Decreases blood glucose levels

Description : Drugs that block the a receptor on effector cells at adrenergic nerve endings (a) Antagonize the effects of isoproterenol on the heart rate (b) Antagonize some of the effects of epinephrine on ... the effects of epinephrine on adenylyl cyclase (d) Cause mydriasis (e) Decreases blood glucose levels

Last Answer : Ans: B

Typical results of beta-receptor activation include which one of the following? (a) Hypoglycemia (b) Lipolysis (c) Glycogen synthesis (d) Decreased skeletal muscle tremor (e) Decreased rennin secretion

Description : Typical results of beta-receptor activation include which one of the following? (a) Hypoglycemia (b) Lipolysis (c) Glycogen synthesis (d) Decreased skeletal muscle tremor (e) Decreased rennin secretion

Last Answer : Ans: B

A 70-year-old man has severe urinary hesitancy associated with benign prostatic hyperplasia. He has tried alpha blockers with little relief. His physician recommends a drug that blocks 5a - reductase in the prostate and writes a prescription for (a) Atropine (b) Clonidine (c) Hydralazine (d) Neostigmine (e) Propranolol

Description : A 70-year-old man has severe urinary hesitancy associated with benign prostatic hyperplasia. He has tried alpha blockers with little relief. His physician recommends a drug that blocks 5a - reductase in ... prescription for (a) Atropine (b) Clonidine (c) Hydralazine (d) Neostigmine (e) Propranolol

Last Answer : Ans: B

Which one of the following drugs, when used chronically, is associated with the development of bone pain and mineralization defects such as osteomalacia? (a) Calcitonin (b) Dihydrotachysterol (c) Ergocalciferol (d) Etidronate (e) Norgestrel

Description : Which one of the following drugs, when used chronically, is associated with the development of bone pain and mineralization defects such as osteomalacia? (a) Calcitonin (b) Dihydrotachysterol (c) Ergocalciferol (d) Etidronate (e) Norgestrel

Last Answer : Ans: D

Clinical uses of Vitamin D do not include (a) Chronic renal failure (b) Hyperparathyroidism (c) Intestinal osteodystrophy (d) Nutritional rickets (e) Osteoporosis

Description : Clinical uses of Vitamin D do not include (a) Chronic renal failure (b) Hyperparathyroidism (c) Intestinal osteodystrophy (d) Nutritional rickets (e) Osteoporosis

Last Answer : Ans: B

Which of the following conditions is an indication for the use of calcitonin? (a) Chronic renal failure (b) Hypoparathyroidism (c) Intestinal osteodystrophy (d) Pager’s disease (e) Rickets

Description : Which of the following conditions is an indication for the use of calcitonin? (a) Chronic renal failure (b) Hypoparathyroidism (c) Intestinal osteodystrophy (d) Pager’s disease (e) Rickets

Last Answer : Ans: D

Which one of the following is lest likely to be useful in the therapy of hypercalcemia? (a) Calcitonin (b) Glucocorticoids (c) Plicamycin (d) Parenteral infusion of phosphate (e) Thiazide diuretics

Description : Which one of the following is lest likely to be useful in the therapy of hypercalcemia? (a) Calcitonin (b) Glucocorticoids (c) Plicamycin (d) Parenteral infusion of phosphate (e) Thiazide diuretics

Last Answer : Ans: E

A drug that is useful in glaucoma and high-altitude sickness is (a) Acetazolamide (b) Amiloride (c) Demeclocycline (d) Desmopressin (e) Ethacrynic acid

Description : A drug that is useful in glaucoma and high-altitude sickness is (a) Acetazolamide (b) Amiloride (c) Demeclocycline (d) Desmopressin (e) Ethacrynic acid

Last Answer : Ans: A

A 55-year-old patient with severe posthepatitis cirrhosis is started on a diuretic for another condition. Two days later he is found in a coma. The drug most likely to cause coma in a patient with cirrhosis is (a) Acetazolamide (b) Amiloride (c) Furosemide (d) Hydrochlorothiazide (e) Spironolactone

Description : A 55-year-old patient with severe posthepatitis cirrhosis is started on a diuretic for another condition. Two days later he is found in a coma. The drug most likely to cause coma in a patient with cirrhosis is (a) Acetazolamide (b) Amiloride (c) Furosemide (d) Hydrochlorothiazide (e) Spironolactone

Last Answer : Ans: A

Which of the following therapies would be most useful in the management of severe hypercalcemia? (a) Amiloride plus saline infusion (b) Furosemide plus saline infusion (c) Hydrochlorothiazide plus saline infusion (d) Mannitol plus saline infusion (e) Spironolactone plus saline infusion

Description : Which of the following therapies would be most useful in the management of severe hypercalcemia? (a) Amiloride plus saline infusion (b) Furosemide plus saline infusion (c) Hydrochlorothiazide plus saline infusion (d) Mannitol plus saline infusion (e) Spironolactone plus saline infusion

Last Answer : Ans: B