Continuous exposure of ctecholaminesensitive cells and tissues to adrenergic agonists causes a progressive diminition in their capacity to respond, this phenomenon is called as (a) Refractoriness (b) Desensitization (c) Tachyphylaxis (d) All of the above

Continuous exposure of ctecholaminesensitive cells and tissues to adrenergic agonists causes a progressive diminition in their capacity to respond, this phenomenon is called as (a) Refractoriness (b) Desensitization (c) Tachyphylaxis (d) All of the above
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Choose the correct statement from the following about a1 – adrenergic receptor agonists (a) Norepinephrine > isoproterenol > epinephrine (b) Norepinephrine < epinephrine > isoproterenol (c) Epinephrine = norepinephrine >> isoproterenol (d) Epinephrine > isoproterenol > norepinephrine

Description : Choose the correct statement from the following about a1 – adrenergic receptor agonists (a) Norepinephrine > isoproterenol > epinephrine (b) Norepinephrine < epinephrine > isoproterenol (c) Epinephrine = norepinephrine >> isoproterenol (d) Epinephrine > isoproterenol > norepinephrine

Last Answer : Ans: C

Select the correct statement from the following about a1 – adrenergic receptor agonists (a) Isoproterenol > epinephrine = norepinephrine (b) Epinephrine > isoproterenol > norepinephrine (c) Isoproterenol = epinephrine = norepinephrine (d) Epinephrine = norepinephrine > isoproterenol

Description : Select the correct statement from the following about a1 – adrenergic receptor agonists (a) Isoproterenol > epinephrine = norepinephrine (b) Epinephrine > isoproterenol > norepinephrine (c) Isoproterenol = epinephrine = norepinephrine (d) Epinephrine = norepinephrine > isoproterenol

Last Answer : Ans: A

Dobutamine differs from dopamine in that (a) It does not activate peripheral dopaminergic receptors (b) It does not activate adrenergic ß receptors (c) It causes pronounced tachycardia (d) It has good blood-brain barrier penetrability

Description : Dobutamine differs from dopamine in that (a) It does not activate peripheral dopaminergic receptors (b) It does not activate adrenergic ß receptors (c) It causes pronounced tachycardia (d) It has good blood-brain barrier penetrability

Last Answer : Ans: A

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

The ß-adrenergic blocker which possesses both ß1 selectivity as well as intrinsic sympathomimetic activity is (a) Alprenolol (b) Atenolol (c) Acebutolol (d) Metoprolol

Description : The ß-adrenergic blocker which possesses both ß1 selectivity as well as intrinsic sympathomimetic activity is (a) Alprenolol (b) Atenolol (c) Acebutolol (d) Metoprolol

Last Answer : Ans: C

Prazosin is an effective antihypertensive while nonselective a adrenergic blockers are not because (a) It is the only orally active a blocker (b) It improves plasma lipid profile (c) It does not concurrently enhance noradrenaline release (d) It improves urine flow in males with prostatic hypertrophy

Description : Prazosin is an effective antihypertensive while nonselective a adrenergic blockers are not because (a) It is the only orally active a blocker (b) It improves plasma lipid profile (c) It does not concurrently enhance noradrenaline release (d) It improves urine flow in males with prostatic hypertrophy

Last Answer : Ans: C

The drug which produces vasoconstriction despite being an a adrenergic blocker is (a) Phenoxybenzamine (b) Ergotamine (c) Dihydroergotoxine (d) Tolazoline

Description : The drug which produces vasoconstriction despite being an a adrenergic blocker is (a) Phenoxybenzamine (b) Ergotamine (c) Dihydroergotoxine (d) Tolazoline

Last Answer : Ans: B

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

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

Last Answer : Ans: D

a2–adrenergic receptors are associated with following except (a) Increase in phospholipase C activity (b) Increase in potassium channel conductance (c) Decrease in calcium channel conductance (d) Increase in adenylyl cyclase activity

Description : a2–adrenergic receptors are associated with following except (a) Increase in phospholipase C activity (b) Increase in potassium channel conductance (c) Decrease in calcium channel conductance (d) Increase in adenylyl cyclase activity

Last Answer : Ans: D

Tyramine induces release of noradrenaline from adrenergic nerve endings (a) By depolarizing the axonal membrane (b) By mobilizing Ca2+ (c) By a nonexocytotic process (d) Only in the presence of MAO inhibitors

Description : Tyramine induces release of noradrenaline from adrenergic nerve endings (a) By depolarizing the axonal membrane (b) By mobilizing Ca2+ (c) By a nonexocytotic process (d) Only in the presence of MAO inhibitors

Last Answer : Ans: C

Insulin release from pancreatic β cells is augmented by the following except: A. Ketone bodies B. Glucagon C. Vagal stimulation D. Alfa adrenergic agonists

Description : Insulin release from pancreatic β cells is augmented by the following except: A. Ketone bodies B. Glucagon C. Vagal stimulation D. Alfa adrenergic agonists

Last Answer : D. Alfa adrenergic agonist

In an anaesthetized dog, repeated intravenous injection of ephedrine shows the phenomenon of: A. Anaphylaxis B. Tachyphylaxis C. Idiosyncrasy D. Drug resistance

Description : In an anaesthetized dog, repeated intravenous injection of ephedrine shows the phenomenon of: A. Anaphylaxis B. Tachyphylaxis C. Idiosyncrasy D. Drug resistance

Last Answer : B. Tachyphylaxis

In an anaesthetized dog, repeated intravenous injection of ephedrine shows the phenomenon of: A. Anaphylaxis B. Tachyphylaxis C. Idiosyncrasy D. Drug resistance

Description : In an anaesthetized dog, repeated intravenous injection of ephedrine shows the phenomenon of: A. Anaphylaxis B. Tachyphylaxis C. Idiosyncrasy D. Drug resistance

Last Answer : B. Tachyphylaxis

When therapeutic effects decline both below and above a narrow range of doses, a drug is said to exhibit: A. Ceiling effect B. Desensitization C. Therapeutic window phenomenon D. Nonreceptor mediated action

Description : When therapeutic effects decline both below and above a narrow range of doses, a drug is said to exhibit: A. Ceiling effect B. Desensitization C. Therapeutic window phenomenon D. Nonreceptor mediated action

Last Answer : C. Therapeutic window phenomenon

When therapeutic effects decline both below and above a narrow range of doses, a drug is said to exhibit: A. Ceiling effect B. Desensitization C. Therapeutic window phenomenon D. Nonreceptor mediated action

Description : When therapeutic effects decline both below and above a narrow range of doses, a drug is said to exhibit: A. Ceiling effect B. Desensitization C. Therapeutic window phenomenon D. Nonreceptor mediated action

Last Answer : C. Therapeutic window phenomenon

Choose the incorrect statement from the following (a) Sympathetic system increases rate of SA node (b) Sympathetic system causes constriction of coronary arteries (c) Sympathetic system causes increased motility of GIT smooth muscles (d) Sympathetic system causes constriction of sphincter in GIT

Description : Choose the incorrect statement from the following (a) Sympathetic system increases rate of SA node (b) Sympathetic system causes constriction of coronary arteries (c) Sympathetic system causes increased motility of GIT smooth muscles (d) Sympathetic system causes constriction of sphincter in GIT

Last Answer : Ans: C

Adrenaline raises blood glucose level by the following actions except (a) Inducing hepatic glycogenolysis (b) Inhibiting insulin secretion from pancreatic ß cells (c) Augmenting glucagons secretion from pancreatic a cells (d) Inhibiting peripheral glucose utilization

Description : Adrenaline raises blood glucose level by the following actions except (a) Inducing hepatic glycogenolysis (b) Inhibiting insulin secretion from pancreatic ß cells (c) Augmenting glucagons secretion from pancreatic a cells (d) Inhibiting peripheral glucose utilization

Last Answer : Ans: D

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

Description : 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

Last Answer : Ans: C

Cromolyn has as its major action (a) Block of calcium channels in lymphocytes (b) Block of mediator release from mast cells (c) Block of phosphodiesterase in mast cells and basophils (d) Smooth muscle relaxation in the bronchi (e) Stimulation of cortisol release by the adrenals

Description : Cromolyn has as its major action (a) Block of calcium channels in lymphocytes (b) Block of mediator release from mast cells (c) Block of phosphodiesterase in mast cells and basophils (d) Smooth muscle relaxation in the bronchi (e) Stimulation of cortisol release by the adrenals

Last Answer : Ans: B

During which step of cellular carcinogenesis do cellular changes exhibit increased malignant behavior? a) Progression During this third step, cells show a propensity to invade adjacent tissues and metastasize. b) Promotion During promotion, repeated exposure to promoting agents causes the expression of abnormal genetic information even after long latency periods. c) Initiation During this first step, initiators such as chemicals, physical factors, and biologic agents escape normal enzymatic mechanisms and alter the genetic structure of cellular DNA. d) Prolongation No stage of cellular carcinogenesis is termed prolongation.

Description : During which step of cellular carcinogenesis do cellular changes exhibit increased malignant behavior? a) Progression During this third step, cells show a propensity to invade adjacent tissues and ... of cellular DNA. d) Prolongation No stage of cellular carcinogenesis is termed prolongation.

Last Answer : a) Progression During this third step, cells show a propensity to invade adjacent tissues and metastasize.

The bladder trigone and prostatic muscles are relaxed by: A. Adrenergic α1 agonists B. Adrenergic α1 antagonists C. Adrenergic α2 agonists D. Adrenergic α2 antagonists

Description : The bladder trigone and prostatic muscles are relaxed by: A. Adrenergic α1 agonists B. Adrenergic α1 antagonists C. Adrenergic α2 agonists D. Adrenergic α2 antagonists

Last Answer : B. Adrenergic α1 antagonists

Adrenergic β2 agonists produce muscle tremor by: A. Facilitating neuromuscular transmission B. Incomplete fusion of contractile response of individual fibres C. Enhanced firing of muscle spindles D. Both (b) and (c) are correct

Description : Adrenergic β2 agonists produce muscle tremor by: A. Facilitating neuromuscular transmission B. Incomplete fusion of contractile response of individual fibres C. Enhanced firing of muscle spindles D. Both (b) and (c) are correct

Last Answer : D. Both (b) and (c) are correct

Which of the following is not the basis for subclassifying β adrenergic receptors into β1 and β2 : A. Selectivity of agonists B. Selectivity of antagonists C. Transducer pathway of response effectuation D. Organ selective location

Description : Which of the following is not the basis for subclassifying β adrenergic receptors into β1 and β2 : A. Selectivity of agonists B. Selectivity of antagonists C. Transducer pathway of response effectuation D. Organ selective location

Last Answer : C. Transducer pathway of response effectuation

Currently, the first choice drug for open angle glaucoma is: A. Miotic eye drops B. Ocular α2 adrenergic agonists C. Ocular prostaglandin analogues D. Ocular β adrenergic blockers

Description : Currently, the first choice drug for open angle glaucoma is: A. Miotic eye drops B. Ocular α2 adrenergic agonists C. Ocular prostaglandin analogues D. Ocular β adrenergic blockers

Last Answer : D. Ocular β adrenergic blockers

In comparison to inhaled β 2 adrenergic agonists, the inhaled anticholinergics: A. Are more effective in bronchial asthma B. Are better suited for control of an acute attack of asthma C. Produce slower response in bronchial asthma D. Produce little benefit in chronic obstructive lung disease

Description : In comparison to inhaled β 2 adrenergic agonists, the inhaled anticholinergics: A. Are more effective in bronchial asthma B. Are better suited for control of an acute attack of asthma C. Produce slower response in bronchial asthma D. Produce little benefit in chronic obstructive lung disease

Last Answer : C. Produce slower response in bronchial asthma

The bladder trigone and prostatic muscles are relaxed by: A. Adrenergic α1 agonists B. Adrenergic α1 antagonists C. Adrenergic α2 agonists D. Adrenergic α2 antagonists

Description : The bladder trigone and prostatic muscles are relaxed by: A. Adrenergic α1 agonists B. Adrenergic α1 antagonists C. Adrenergic α2 agonists D. Adrenergic α2 antagonists

Last Answer : B. Adrenergic α1 antagonists

Adrenergic β2 agonists produce muscle tremor by: A. Facilitating neuromuscular transmission B. Incomplete fusion of contractile response of individual fibres C. Enhanced firing of muscle spindles D. Both (b) and (c) are correct

Description : Adrenergic β2 agonists produce muscle tremor by: A. Facilitating neuromuscular transmission B. Incomplete fusion of contractile response of individual fibres C. Enhanced firing of muscle spindles D. Both (b) and (c) are correct

Last Answer : D. Both (b) and (c) are correct

Which of the following is not the basis for subclassifying β adrenergic receptors into β 1 and β 2: A. Selectivity of agonists B. Selectivity of antagonists C. Transducer pathway of response effectuation D. Organ selective location

Description : Which of the following is not the basis for subclassifying β adrenergic receptors into β 1 and β 2: A. Selectivity of agonists B. Selectivity of antagonists C. Transducer pathway of response effectuation D. Organ selective location

Last Answer : C. Transducer pathway of response effectuation

Currently, the first choice drug for open angle glaucoma is: A. Miotic eye drops B. Ocular α2 adrenergic agonists C. Ocular prostaglandin analogues D. Ocular β adrenergic blockers

Description : Currently, the first choice drug for open angle glaucoma is: A. Miotic eye drops B. Ocular α2 adrenergic agonists C. Ocular prostaglandin analogues D. Ocular β adrenergic blockers

Last Answer : D. Ocular β adrenergic blockers

Characteristics of Vitamin D and its metabolites include which one of the following? (a) Act to decrease serum levels of calcium (b) Activation of their Vitamin D receptors increases cellular CAMP (c) Calcitriol is the major derivative responsible for increasing intestinal absorption of phosphate (d) Metabolites of Vitamin D increase renal excretion of calcium (e) Vitamin D deficiency results in Pager’s disease

Description : Characteristics of Vitamin D and its metabolites include which one of the following? (a) Act to decrease serum levels of calcium (b) Activation of their Vitamin D receptors increases cellular CAMP ... Vitamin D increase renal excretion of calcium (e) Vitamin D deficiency results in Pager's disease

Last Answer : Ans: C

The synaptic pre-ganglionic neurons have their cell bodies in the lateral horn of the grey matter of the (a) Thoracic segment only (b) Lumbar segment only (c) Both (a) and (b) (d) None of the above

Description : The synaptic pre-ganglionic neurons have their cell bodies in the lateral horn of the grey matter of the (a) Thoracic segment only (b) Lumbar segment only (c) Both (a) and (b) (d) None of the above

Last Answer : Ans: C

Phenylephrine (a) Mimics the transmitter at post-synaptic receptors (b) Displaces transmitter from axonal terminal (c) Inhibits synthesis of transmitter (d) None of the above

Description : Phenylephrine (a) Mimics the transmitter at post-synaptic receptors (b) Displaces transmitter from axonal terminal (c) Inhibits synthesis of transmitter (d) None of the above

Last Answer : Ans: A

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

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

Last Answer : Ans: D

Propanolol can be used to allay anxiety associated with (a) Chronic neurotic disorer (b) Schizopherenia (c) Short-term stressful situation (d) Endogenous depression

Description : Propanolol can be used to allay anxiety associated with (a) Chronic neurotic disorer (b) Schizopherenia (c) Short-term stressful situation (d) Endogenous depression

Last Answer : Ans: C

Which of the following is true of sildenafil (a) It enhances sexul enjoyment in normal men (b) It delays ejaculation (c) It is indicated only for treatment of erectile dysfunction in men (d) It blocks cavernosal a2 adrenoceptors

Description : Which of the following is true of sildenafil (a) It enhances sexul enjoyment in normal men (b) It delays ejaculation (c) It is indicated only for treatment of erectile dysfunction in men (d) It blocks cavernosal a2 adrenoceptors

Last Answer : Ans: C

Guanethidine inhibits (a) Synthesis of transmitter (b) Metabolism of transmitter (c) Release of transmitter (d) Displacement of transmitter from axonal terminal

Description : Guanethidine inhibits (a) Synthesis of transmitter (b) Metabolism of transmitter (c) Release of transmitter (d) Displacement of transmitter from axonal terminal

Last Answer : Ans: C

Vasoconstrictors should not be used in (a) Neurogenic shock (b) Haemorrhagic shock (c) Secondary shock (d) Hypotension due to spinal anaesthesia

Description : Vasoconstrictors should not be used in (a) Neurogenic shock (b) Haemorrhagic shock (c) Secondary shock (d) Hypotension due to spinal anaesthesia

Last Answer : Ans: C

While undergoing a surgical procedure a patient develops hypotension. Which of the following drugs can be injected intramuscularly to raise his BP (a) Noradrenaline (b) Isoprenaline (c) Mephentermine (d) Isoxsuprine

Description : While undergoing a surgical procedure a patient develops hypotension. Which of the following drugs can be injected intramuscularly to raise his BP (a) Noradrenaline (b) Isoprenaline (c) Mephentermine (d) Isoxsuprine

Last Answer : Ans: C

Noradrenaline is administered by (a) Subcutaneous injection (b) Intramuscular injection (c) Slow intravenous infusion (d) All of the above routes

Description : Noradrenaline is administered by (a) Subcutaneous injection (b) Intramuscular injection (c) Slow intravenous infusion (d) All of the above routes

Last Answer : Ans: C

Low doses of adrenaline dilate the following vascular bed (a) Cutaneous (b) Mucosal (c) Renal (d) Skeletal muscle

Description : Low doses of adrenaline dilate the following vascular bed (a) Cutaneous (b) Mucosal (c) Renal (d) Skeletal muscle

Last Answer : Ans: D

A sympathomimetic amine that acts almost exclusively by releasing noradrenaline from the nerve endings is (a) Ephedrine (b) Dopamine (c) Isoprenaline (d) Tyramine

Description : A sympathomimetic amine that acts almost exclusively by releasing noradrenaline from the nerve endings is (a) Ephedrine (b) Dopamine (c) Isoprenaline (d) Tyramine

Last Answer : Ans: D

The most efficacious inhibitor of catecholamine synthesis in the body is (a) a - methyl – p - tyrosine (b) a - methyldopa (c) a - methyl - norepinephrine (d) Pyrogallol

Description : The most efficacious inhibitor of catecholamine synthesis in the body is (a) a - methyl – p - tyrosine (b) a - methyldopa (c) a - methyl - norepinephrine (d) Pyrogallol

Last Answer : Ans: A

Atropine is contraindicated in (a) Cyclic AMP (b) Inositol trisphosphate (c) Diacyl glycerols (d) G protein

Description : Atropine is contraindicated in (a) Cyclic AMP (b) Inositol trisphosphate (c) Diacyl glycerols (d) G protein

Last Answer : Ans: D

The most effective antidote for belladonna poisoning is (a) Neostigmine (b) Physostigmine (c) Pilocarpine (d) Methacholine

Description : The most effective antidote for belladonna poisoning is (a) Neostigmine (b) Physostigmine (c) Pilocarpine (d) Methacholine

Last Answer : Ans: B

The most suitable mydratic for a patient of corneal ulcer is (a) Atropine sulfate (b) Homatropine (c) Cyclopentolate (d) Tropicamide

Description : The most suitable mydratic for a patient of corneal ulcer is (a) Atropine sulfate (b) Homatropine (c) Cyclopentolate (d) Tropicamide

Last Answer : Ans: A

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

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

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

Which of the following anticholinergic drugs is primarily used in preanaesthetic medication and during surgery (a) Glycopyrrolate (b) Pipenzolate methyl bromide (c) Isopropamide (d) Dicyclomine

Description : Which of the following anticholinergic drugs is primarily used in preanaesthetic medication and during surgery (a) Glycopyrrolate (b) Pipenzolate methyl bromide (c) Isopropamide (d) Dicyclomine

Last Answer : Ans: A

Hyoscine differs from atropine in that it (a) Exerts depressant effects on the CNS at relatively low doses (b) Exerts more potent effects on the heart than on the eye (c) Is longer acting (d) Has weaker antimotion sickness activity

Description : Hyoscine differs from atropine in that it (a) Exerts depressant effects on the CNS at relatively low doses (b) Exerts more potent effects on the heart than on the eye (c) Is longer acting (d) Has weaker antimotion sickness activity

Last Answer : Ans: A

a1 – receptors are coupled with _______ G protein. (a) Gs (b) Gi (c) Gq (d) Go

Description : a1 – receptors are coupled with _______ G protein. (a) Gs (b) Gi (c) Gq (d) Go

Last Answer : Ans: C