Vasomotor reversal phenomenon after administration of an α adrenergic blocker is seen with: A. Adrenaline B. Noradrenaline C. Isoprenaline D. All of the above drugs

Vasomotor reversal phenomenon after administration
of an α adrenergic blocker is seen with:
A. Adrenaline
B. Noradrenaline
C. Isoprenaline
D. All of the above drugs
by

1 Answer

Answer :

A. Adrenaline
by

Related questions

Vasomotor reversal phenomenon after administration of an α adrenergic blocker is seen with: A. Adrenaline B. Noradrenaline C. Isoprenaline D. All of the above drugs

Description : Vasomotor reversal phenomenon after administration of an α adrenergic blocker is seen with: A. Adrenaline B. Noradrenaline C. Isoprenaline D. All of the above drugs

Last Answer : A. Adrenaline

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

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

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

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

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

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

The following sympathomimetic amine has agonistic action on α 1 + α 2 + β 1 + β 3 adrenoceptors, but not on β 2 receptors: A. Adrenaline B. Noradrenaline C. Isoprenaline D. Phenylephrine

Description : The following sympathomimetic amine has agonistic action on α 1 + α 2 + β 1 + β 3 adrenoceptors, but not on β 2 receptors: A. Adrenaline B. Noradrenaline C. Isoprenaline D. Phenylephrine

Last Answer : B. Noradrenaline

Adrenergic neurone blocking drugs: A. Block the action of adrenaline on neuronal α2 adrenoceptors B. Block both α and β adrenoceptor mediated effects of injected adrenaline C. Do not block any effect of injected adrenaline D. Do not block the effects of sympathetic nerve

Description : Adrenergic neurone blocking drugs: A. Block the action of adrenaline on neuronal α2 adrenoceptors B. Block both α and β adrenoceptor mediated effects of injected adrenaline C. Do not block any effect of injected adrenaline D. Do not block the effects of sympathetic nerve

Last Answer : C. Do not block any effect of injected adrenaline

Adrenergic neurone blocking drugs: A. Block the action of adrenaline on neuronal α2 adrenoceptors B. Block both α and β adrenoceptor mediated effects of injected adrenaline C. Do not block any effect of injected adrenaline D. Do not block the effects of sympathetic nerve stimulation

Description : Adrenergic neurone blocking drugs: A. Block the action of adrenaline on neuronal α2 adrenoceptors B. Block both α and β adrenoceptor mediated effects of injected adrenaline C. Do not block any effect of injected adrenaline D. Do not block the effects of sympathetic nerve stimulation

Last Answer : C. Do not block any effect of injected adrenaline

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 noradrenaline which acts as a false transmitter in peripheral adrenergic nerve endings D. Activating vascular dopamine receptors

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

The drug which produces vasoconstriction despite being an α adrenergic blocker is: A. Phenoxybenzamine B. Ergotamine C. Dihydroergotoxine D. Tolazoline

Description : The drug which produces vasoconstriction despite being an α adrenergic blocker is: A. Phenoxybenzamine B. Ergotamine C. Dihydroergotoxine D. Tolazoline

Last Answer : B. Ergotamine

The following sympathomimetic amine has agonistic action on α1 + α2 + β1 + β3 adrenoceptors, but not on β2 receptors: A. Adrenaline B. Noradrenaline C. Isoprenaline D. Phenylephrine

Description : The following sympathomimetic amine has agonistic action on α1 + α2 + β1 + β3 adrenoceptors, but not on β2 receptors: A. Adrenaline B. Noradrenaline C. Isoprenaline D. Phenylephrine

Last Answer : B. Noradrenaline

While undergoing a surgical procedure a patient deve- lops hypotension. Which drug can be injected intramuscularly to raise his BP: A. Noradrenaline B. Isoprenaline C. Mephentermine D. Isoxsuprine

Description : While undergoing a surgical procedure a patient deve- lops hypotension. Which drug can be injected intramuscularly to raise his BP: A. Noradrenaline B. Isoprenaline C. Mephentermine D. Isoxsuprine

Last Answer : C. Mephentermine

While undergoing a surgical procedure a patient develops hypotension. Which drug 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 drug can be injected intramuscularly to raise his BP: A. Noradrenaline B. Isoprenaline C. Mephentermine D. Isoxsuprine

Last Answer : C. Mephentermine

While undergoing a surgical procedure a patient develops hypotension. Which drug 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 drug can be injected intramuscularly to raise his BP: A. Noradrenaline B. Isoprenaline C. Mephentermine D. Isoxsuprine

Last Answer : C. Mephentermine

Which of the following is a noncatecholamine sympathomimetic: A. Adrenaline B. Ephedrine C. Dopamine D. Isoprenaline

Description : Which of the following is a noncatecholamine sympathomimetic: A. Adrenaline B. Ephedrine C. Dopamine D. Isoprenaline

Last Answer : B. Ephedrine

Which of the following is a noncatecholamine sympathomimetic: A. Adrenaline B. Ephedrine C. Dopamine D. Isoprenaline

Description : Which of the following is a noncatecholamine sympathomimetic: A. Adrenaline B. Ephedrine C. Dopamine D. Isoprenaline

Last Answer : B. Ephedrine

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 adrenergic tocolytic preferred for arresting labour is: A. Ritodrine B. Isoprenaline C. Salbutamol D. Terbutaline

Description : The adrenergic tocolytic preferred for arresting labour is: A. Ritodrine B. Isoprenaline C. Salbutamol D. Terbutaline

Last Answer : A. Ritodrine

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

The neuromuscular blocker that does not need reversal of action by neostigmine at the end of the operation is: A. d-Tubocurarine B. Doxacurium C. Pipecuronium D. Mivacurium

Description : The neuromuscular blocker that does not need reversal of action by neostigmine at the end of the operation is: A. d-Tubocurarine B. Doxacurium C. Pipecuronium D. Mivacurium

Last Answer : D. Mivacurium

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

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

The following is true of β-adrenergic blocker therapy in CHF: A. They are added to conventional therapy after cardiac compensation is restored B. They are indicated only in severe (NYHA class IV) heart failure C. They are to be used only at low doses D. All of the above

Description : The following is true of β-adrenergic blocker therapy in CHF: A. They are added to conventional therapy after cardiac compensation is restored B. They are indicated only in severe (NYHA class IV) heart failure C. They are to be used only at low doses D. All of the above

Last Answer : A. They are added to conventional therapy after cardiac compensation is restored

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

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

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

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

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 : C. By a nonexocytotic process

The following is true of propafenone except: A. It is a weak Na+ channel blocker B. It markedly delays recovery of myocardial Na+ channels C. It has additional β-adrenergic blocking property D. It slows anterograde as well as retrograde conduction in the WPW bypass tract

Description : The following is true of propafenone except: A. It is a weak Na+ channel blocker B. It markedly delays recovery of myocardial Na+ channels C. It has additional β-adrenergic blocking property D. It slows anterograde as well as retrograde conduction in the WPW bypass tract

Last Answer : A. It is a weak Na+ channel blocker

The primary reason for preferring phentolamine as the α adrenergic blocker for performing diagnostic test for pheochromocytoma is: A. It produces rapid and short lasting α-adrenergic blockade B. It equally blocks α1 and α2 adrenoceptors C. It is the most potent α blocker D. It has no additional β adrenergic blocking property

Description : The primary reason for preferring phentolamine as the α adrenergic blocker for performing diagnostic test for pheochromocytoma is: A. It produces rapid and short lasting α-adrenergic blockade B. It equally ... It is the most potent α blocker D. It has no additional β adrenergic blocking property

Last Answer : A. It produces rapid and short lasting α-adrenergic blockade

The drug which produces vasoconstriction despite being an α adrenergic blocker is: A. Phenoxybenzamine B. Ergotamine C. Dihydroergotoxine D. Tolazoline

Description : The drug which produces vasoconstriction despite being an α adrenergic blocker is: A. Phenoxybenzamine B. Ergotamine C. Dihydroergotoxine D. Tolazoline

Last Answer : B. Ergotamine

Dihydroergotamine (DHE) differs from ergotamine in the following respect: A. It is a more potent oxytocic B. It has antiemetic property C. It has high oral bioavailability D. It is a more potent α adrenergic blocker and less potent vasoconstrictor

Description : Dihydroergotamine (DHE) differs from ergotamine in the following respect: A. It is a more potent oxytocic B. It has antiemetic property C. It has high oral bioavailability D. It is a more potent α adrenergic blocker and less potent vasoconstrictor

Last Answer : D. It is a more potent α adrenergic blocker and less potent vasoconstrictor

Select the β -adrenergic blocker that has additional α 1 blocking, vasodilator and antioxidant properties: A. Carvedilol B. Celiprolol C. Acebutolol D. Metoprolol

Description : Select the β -adrenergic blocker that has additional α 1 blocking, vasodilator and antioxidant properties: A. Carvedilol B. Celiprolol C. Acebutolol D. Metoprolol

Last Answer : A. Carvedilol

The primary reason for preferring phentolamine as the α adrenergic blocker for performing diagnostic test for pheochromocytoma is: A. It produces rapid and short lasting α-adrenergic blockade B. It equally blocks α1 and α2 adrenoceptors C. It is the most potent α blocker D. It has no additional β adrenergic blocking property

Description : The primary reason for preferring phentolamine as the α adrenergic blocker for performing diagnostic test for pheochromocytoma is: A. It produces rapid and short lasting α-adrenergic blockade B. It equally ... It is the most potent α blocker D. It has no additional β adrenergic blocking property

Last Answer : A. It produces rapid and short lasting α-adrenergic blockade

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

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

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

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

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 α and β 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 α and β adrenergic effects

Last Answer : D. Producing both α and β adrenergic effects

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 α and β 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 α and β adrenergic effects

Last Answer : D. Producing both α and β adrenergic effects

Choose the correct statement about latanoprost: A. It is a PGF2α derivative used in glaucoma B. It is a selective α1 blocker used in benign hypertrophy of prostate C. It is a 5-α-reductase inhibitor used to reduce the size of enlarged prostate gland D. It is a PGE2 analogue used intravaginally for cervical priming

Description : Choose the correct statement about latanoprost: A. It is a PGF2α derivative used in glaucoma B. It is a selective α1 blocker used in benign hypertrophy of prostate C. It is a 5-α- ... reduce the size of enlarged prostate gland D. It is a PGE2 analogue used intravaginally for cervical priming

Last Answer : A. It is a PGF2α derivative used in glaucoma

Choose the correct statement about latanoprost: A. It is a PGF2α derivative used in glaucoma B. It is a selective α1 blocker used in benign hypertrophy of prostate C. It is a 5-α-reductase inhibitor used to reduce the size of enlarged prostate gland D. It is a PGE2 analogue used intravaginally for cervical priming

Description : Choose the correct statement about latanoprost: A. It is a PGF2α derivative used in glaucoma B. It is a selective α1 blocker used in benign hypertrophy of prostate C. It is a 5-α- ... reduce the size of enlarged prostate gland D. It is a PGE2 analogue used intravaginally for cervical priming

Last Answer : A. It is a PGF2α derivative used in glaucoma

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

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 : D. Tyramine

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 : D. Tyramine

Adrenaline raises blood glucose level by the following actions except: A. Inducing hepatic glycogenolysis B. Inhibiting insulin secretion from pancreatic β cells C. Augmenting glucagon secretion from pancreatic α 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 β cells C. Augmenting glucagon secretion from pancreatic α cells D. Inhibiting peripheral glucose utilization

Last Answer : D. Inhibiting peripheral glucose utilization

Adrenaline raises blood glucose level by the following actions except: A. Inducing hepatic glycogenolysis B. Inhibiting insulin secretion from pancreatic β cells C. Augmenting glucagon secretion from pancreatic α 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 β cells C. Augmenting glucagon secretion from pancreatic α cells D. Inhibiting peripheral glucose utilization

Last Answer : D. Inhibiting peripheral glucose utilization

A patient has an episode of hematemesis following streptokinase infused for the treatment of deep vein thrombosis. Which of the following drugs would be most effective in controlling the bleeding episode: A. Vitamin K B. Noradrenaline C. Epsilon aminocaproic acid D. Rutin

Description : A patient has an episode of hematemesis following streptokinase infused for the treatment of deep vein thrombosis. Which of the following drugs would be most effective in controlling the bleeding episode: A. Vitamin K B. Noradrenaline C. Epsilon aminocaproic acid D. Rutin

Last Answer : C. Epsilon aminocaproic acid

Procainamide differs from quinidine in the following respect(s): A. It does not cause paradoxical tachycardia B. It has no α adrenergic blocking activity C. It has little antivagal action D. Both ‘B’ and ‘C’ are corre

Description : Procainamide differs from quinidine in the following respect(s): A. It does not cause paradoxical tachycardia B. It has no α adrenergic blocking activity C. It has little antivagal action D. Both ‘B’ and ‘C’ are corre

Last Answer : D. Both ‘B’ and ‘C’ are correct

Procainamide differs from quinidine in the following respect(s): A. It does not cause paradoxical tachycardia B. It has no α adrenergic blocking activity C. It has little antivagal action D. Both ‘B’ and ‘C’ are correct

Description : Procainamide differs from quinidine in the following respect(s): A. It does not cause paradoxical tachycardia B. It has no α adrenergic blocking activity C. It has little antivagal action D. Both ‘B’ and ‘C’ are correct

Last Answer : D. Both ‘B’ and ‘C’ are correct

The following drug claimed to have a therapeutic effect in senile dementia has α adrenergic blocking activity: A. Piracetam B. Pyritinol C. Codergocrine D. Methylphenidate

Description : The following drug claimed to have a therapeutic effect in senile dementia has α adrenergic blocking activity: A. Piracetam B. Pyritinol C. Codergocrine D. Methylphenidate

Last Answer : C. Codergocrine

6.12 The most prominent action of bromocriptine is: A. Dopamine D2 agonism B. Dopamine D2 antagonism C. Dopamine D1 antagonism D. α adrenergic antagonism

Description : 6.12 The most prominent action of bromocriptine is: A. Dopamine D2 agonism B. Dopamine D2 antagonism C. Dopamine D1 antagonism D. α adrenergic antagonism

Last Answer : A. Dopamine D2 agonism

Labetalol has: A. More potent β adrenergic blocking than α blocking activity B. More potent α adrenergic blocking than β blocking activity C. Equal α and β adrenergic blocking activity D. β1 agonistic activity in addition to α and β adrenergic blockade

Description : Labetalol has: A. More potent β adrenergic blocking than α blocking activity B. More potent α adrenergic blocking than β blocking activity C. Equal α and β adrenergic blocking activity D. β1 agonistic activity in addition to α and β adrenergic blockade

Last Answer : A. More potent β adrenergic blocking than α blocking activity

Ergotamine relieves migraine by: A. Blocking vascular α adrenergic receptors B. Blocking vascular 5-HT2 receptors C. Dilating cranial arterio-venous shunt channels D. Constricting cranial vessels and reducing perivascular neurogenic inflammation

Description : Ergotamine relieves migraine by: A. Blocking vascular α adrenergic receptors B. Blocking vascular 5-HT2 receptors C. Dilating cranial arterio-venous shunt channels D. Constricting cranial vessels and reducing perivascular neurogenic inflammation

Last Answer : D. Constricting cranial vessels and reducing perivascular neurogenic inflammation

The nonselective α adrenergic blockers produce the following actions except: A. Postural hypotension B. Bradycardia C. Miosis D. Inhibition of ejaculation

Description : The nonselective α adrenergic blockers produce the following actions except: A. Postural hypotension B. Bradycardia C. Miosis D. Inhibition of ejaculation

Last Answer : B. Bradycardia

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 : 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

Last Answer : B. Prejunctional, postjunctional as well as extrajunctional in location