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 : C. By a nonexocytotic process
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
Description : The principal process which terminates the action of noradrenaline released from adrenergic nerve ending is: A. Degradation by MAO B. Methylation by COMT C. Axonal uptake D. Extraneuronal uptake
Last Answer : C. Axonal uptake
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
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
Description : Rapid intravenous injection of clonidine causes rise in BP due to: A. Stimulation of vasomotor centre B. Release of noradrenaline from adrenergic nerve endings C. Agonistic action on vascular α2 adrenergic receptors D. Cardiac stimulation
Last Answer : C. Agonistic action on vascular α2 adrenergic receptors
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 : D. Tyramine
Description : At the adrenergic synapse, the concentration of adrenaline in synaptic cleft: a. increased by cocaine which inhibit reuptake of adrenaline b. decreased by MAO (monoamine oxidase) - inhibitors c. controlled chiefly by the activity of the enzyme COMT d. increased by noradrenaline receptor blockers
Last Answer : increased by cocaine which inhibit reuptake of adrenaline
Description : Guanethidine inhibits (a) Synthesis of transmitter (b) Metabolism of transmitter (c) Release of transmitter (d) Displacement of transmitter from axonal terminal
Description : Methyldopa lowers BP by: A. Inhibiting dopa decarboxylase in adrenergic nerve endings B. Generating α-methyl noradrenaline in brain which reduces sympathetic tone C. Generating α-methyl ... as a false transmitter in peripheral adrenergic nerve endings D. Activating vascular dopamine receptors
Last Answer : B. Generating α-methyl noradrenaline in brain which reduces sympathetic tone
Description : The usual cardiovascular effect of levodopa is: A. Bradycardia due to increased vagal tone B. Rise in blood pressure due to increased noradrenaline content of adrenergic nerve endings C. Fall in blood pressure due to decrease in sympathetic tone D. Both ‘A’ and ‘B’ are correct
Last Answer : C. Fall in blood pressure due to decrease in sympathetic tone
Description : In the autonomic regulation of blood pressure (a) Cardiac output is maintained constant at the expense of other hemodynamic variables (b) Elevation of blood pressure results in elevated ... the sensitivity of the sensory baroreceptor nerve endings might cause an increase in sympathetic discharge
Description : Dantrolene sodium reduces skeletal muscle tone by: A. Reducing acetylcholine release from motor nerve endings B. Suppressing spinal polysynaptic reflexes C. Inhibiting the generation of muscle action potential D. Reducing Ca2+ release from sarcoplasmic reticulum in the muscle fibre
Last Answer : D. Reducing Ca2+ release from sarcoplasmic reticulum in the muscle fibre
Description : All of the following contribute to the antihypertensive action of propranolol except: A. Direct vasodilatation B. Decreased renin release from kidney C. Adaptation of blood vessels to reduced cardiac output D. Less noradrenaline release from sympathetic nerve endings
Last Answer : A. Direct vasodilatation
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
Description : Which of the following adrenergic inhibitors acts directly on the blood vessels, producing vasodilation? a) Prazosin hydrochloride (Minipress) Minipress is a peripheral vasodilator acting ... through centrally mediated alpha-adrenergic stimulation in the brain, producing blood pressure reduction.
Last Answer : a) Prazosin hydrochloride (Minipress) Minipress is a peripheral vasodilator acting directly on the blood vessel. It is not used in angina and coronary artery disease, however, because it induces tachycardia if not preceded by administration of propranolol and a diuretic.
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
Description : Noradrenaline is administered by (a) Subcutaneous injection (b) Intramuscular injection (c) Slow intravenous infusion (d) All of the above routes
Description : The following are neurotransmitters at the autonomic post-ganglionic nerve endings: a. GABA b. noradrenaline c. acetylcholine d. 5 HT
Last Answer : acetylcholine
Description : Postural hypotension is a common adverse effect of which one of the following types of drugs ? (a) ACE inhibitors (b) Alpha-receptor blockers (c) Arteriolar dilators (d) ß1 – selective receptor blockers (e) Nonselective ß - blockers
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
Description : The drug which produces vasoconstriction despite being an a adrenergic blocker is (a) Phenoxybenzamine (b) Ergotamine (c) Dihydroergotoxine (d) Tolazoline
Description : 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
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
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
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
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
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
Description : Adrenaline is inactive orally because it is: A. Not absorbed from the gastrointestinal tract B. Destroyed by gastric acid C. Completely metabolized in the intestinal mucosa and liver before reaching systemic circulation D. Taken up by adrenergic nerve endings of the intestinal wall, liver and lungs
Last Answer : C. Completely metabolized in the intestinal mucosa and liver before reaching systemic circulation
Description : The α2 adrenoceptors are: A. Located exclusively on the adrenergic nerve endings B. Prejunctional, postjunctional as well as extrajunctional in location C. Selectively activated by phenylephrine D. Selectively blocked by clonidine
Last Answer : B. Prejunctional, postjunctional as well as extrajunctional in location
Description : The α 2 adrenoceptors are: A. Located exclusively on the adrenergic nerve endings B. Prejunctional, postjunctional as well as extrajunctional in location C. Selectively activated by phenylephrine D. Selectively blocked by clonidine
Description : Prazosin is an effective antihypertensive while nonselective α adrenergic blockers are not because: A. It is the only orally active α 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 : C. It does not concurrently enhance noradrenaline release
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
Description : Choose the correct statement about moclobemide: A. It is a reversible inhibitor of MAO-A with short duration of action B. Patients taking it need to be cautioned not to consume tyramine rich food C. It is contraindicated in elderly patients D. It produces anticholinergic side effect
Last Answer : A. It is a reversible inhibitor of MAO-A with short duration of action
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
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
Description : Which of the following statement(s) is/are true concerning the neuroendocrine responses to shock? a. Sympathetic nerve endings release epinephrine which is responsible for greater than 80% ... injury and sepsis d. The renin-angiotensin axis further augments the sympathetic-mediated vasoconstriction
Last Answer : Answer: c, d The neuroendocrine response to shock attempts to achieve restoration of effective blood volume, mobilization of metabolic substrates, and maintenance of central ... . Angiotensin II is an extremely effective vasoconstrictor that further augments sympathetic-mediated vasoconstriction
Description : The following type/types of noradrenaline uptake is blocked by reserpine: A. Axonal uptake B. Granular uptake C. Extraneuronal uptake D. All of the above
Last Answer : B. Granular uptake
Description : Which of the following MAO inhibitors is most likely to produce cheese reaction: A. Tranylcypromine B. Moclobemide C. Selegiline D. Clorgyline
Last Answer : A. Tranylcypromine
Description : The nonselective MAO inhibitors are not used clinically as antidepressants because of their: A. Low antidepressant efficacy B. Higher toxicity C. Potential to interact with many foods and drugs D. Both 'B' and 'C' are correct
Last Answer : D. Both 'B' and 'C' are correct
Description : The following drug of abuse is a hallucinogen: A. Cocaine B. Cannabis C. Heroin D. Methaqualone (p. 403) 31.1 Which of the following is a selective MAO-B inhibitor: A. Selegiline
Last Answer : B. Cannabis
Description : Monitoring plasma drug concentration is useful while using: A. Antihypertensive drugs B. Levodopa C. Lithium carbonate D. MAO inhibitors
Last Answer : C. Lithium carbonate