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

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
by

1 Answer

Answer :

A. Direct vasodilatation
by

Related questions

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

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

The most likely mechanism of antihypertensive action of thiazide diuretics in the long-term is: A. Reduction of circulating blood volume B. Reduction in cardiac output C. Decreased sympathetic tone D. Reduction in total peripheral vascular resistance and improved compliance of resistance vessels

Description : The most likely mechanism of antihypertensive action of thiazide diuretics in the long-term is: A. Reduction of circulating blood volume B. Reduction in cardiac output C. Decreased sympathetic tone D. Reduction in total peripheral vascular resistance and improved compliance of resistance vessels

Last Answer : D. Reduction in total peripheral vascular resistance and improved compliance of resistance vessels

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

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Last Answer : C. Agonistic action on vascular α2 adrenergic receptors

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

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The following factors enhance renin release from the kidney except: A. Fall in blood pressure B. Reduction in blood volume C. Enhanced sympathetic activity D. Volume overload

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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

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Last Answer : B. Generating α-methyl noradrenaline in brain which reduces sympathetic tone

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% of systemic vascular resistance b. Endogenous epinephrine is the primary contributor to systemic vascular resistance c. Increased pancreatic secretion of glucagon contributes to glucose intolerance associated with injury and sepsis d. The renin-angiotensin axis further augments the sympathetic-mediated vasoconstriction

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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

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Last Answer : C. By a nonexocytotic process

The following action of adrenaline is not mediated by β receptors: A. Dilatation of blood vessels B. Dilatation of pupil C. Bronchodilation D. Renin release from kidney

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Actions of angiotensin II include: a. increases the release of aldosterone b. reduces renin release from the kidney c. vasodilatation d. promotes microalbuminuria

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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

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The following factor is not involved in the causation of hypotension due to spinal anaesthesia: A. Histamine release B. Reduced sympathetic vasoconstrictor tone C. Decreased venous return from the lower limbs D. Bradycardia

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Methyldopa differs from clonidine in the following respect: A. It is less likely to cause rebound hypertension on sudden discontinuation B. It does not reduce plasma renin activity C. It has a central as well as peripheral site of antihypertensive action D. It does not produce central side effect

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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

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Last Answer : Ans: C

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

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Last Answer : C. By a nonexocytotic process

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

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The antianginal effect of propranolol may be attributed to which one of the following (a) Block of exercise – induced tachycardia (b) Decreased end – diastolic ventricular volume (c) Dilation of consticted coronary vessels (d) Increased cardiac force (e) Increased resting heart rate

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Advantages of angiotensin converting enzyme inhibitors as antihypertensive include the following except: A. They tend to reverse left ventricular hypertrophy B. Their efficacy is not reduced by nonsteroidal antiinflammatory drugs C. They do not worsen blood lipid profile D. They do not impair work performance

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A woman in the 28th week of pregnancy has developed pregnancy induced hypertension with a blood pressure reading of 150/100 mm Hg. Select the most appropriate antihypertensive drug for her: A. Furosemide B. Methyldopa C. Propranolol D. Captopril

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The following antihypertensive drug tends to lower plasma renin activity: A. Clonidine B. Hydralazine C. Nifedipine D. Captopril

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

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The following are neurotransmitters at the autonomic post-ganglionic nerve endings: a. GABA b. noradrenaline c. acetylcholine d. 5 HT

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Raised plasma aldosterone level in CHF contributes to disease progression by exerting the following effects except: A. Fibrotic remodeling of myocardium B. Hyperkalemia and hypermagnesemia C. Increasing cardiac preload by Na+ and water retention D. Enhancing cardiotoxicity of sympathetic overactivity

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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

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The effect of noradrenaline on the heart include: a. tachycardiac b. increased duration of the cardiac action potential c. decreased potassium conductance of the membranes of pacemaker cells d. increased strength of cardiac contraction

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The antihypertensive action of calcium channel blockers is characterized by the following except: A. Delayed onset; blood pressure starts falling after 1–2 weeks therapy B. Lack of central side effects C. No compromise of male sexual function D. Safety in peripheral vascular diseases

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The following antihypertensive drug has a favourable effect on plasma lipid profile: A. Prazosin B. Propranolol C. Hydrochlorothiazide D. Furosemide

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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

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Description : The following drug increases cardiac output in congestive heart failure without having any direct myocardial action: A. Captopril B. Digoxin C. Amrinone D. Dobutamine

Last Answer : A. Captopril

The action of histamine that is not mediated through H1 receptors is: A. Release of EDRF from vascular endothelium resulting in vasodilatation B. Direct action on vascular smooth muscle causing vasodilatation C. Bronchoconstriction D. Release of catecholamines from adrenal medulla

Description : The action of histamine that is not mediated through H1 receptors is: A. Release of EDRF from vascular endothelium resulting in vasodilatation B. Direct action on vascular smooth muscle causing vasodilatation C. Bronchoconstriction D. Release of catecholamines from adrenal medulla

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The action of histamine that is not mediated through H1 receptors is: A. Release of EDRF from vascular endothelium resulting in vasodilatation B. Direct action on vascular smooth muscle causing vasodilatation C. Bronchoconstriction D. Release of catecholamines from adrenal medulla

Description : The action of histamine that is not mediated through H1 receptors is: A. Release of EDRF from vascular endothelium resulting in vasodilatation B. Direct action on vascular smooth muscle causing vasodilatation C. Bronchoconstriction D. Release of catecholamines from adrenal medulla

Last Answer : B. Direct action on vascular smooth muscle causing vasodilatation

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

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

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Last Answer : B. Increased peristalsis of gut

As antihypertensives the thiazide diuretics have the following advantages except: A. High ceiling antihypertensive action B. Absence of CNS side effects C. Absence of tolerance development D. Low cost

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Last Answer : A. High ceiling antihypertensive action

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

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

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

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

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

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

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