The GABAB receptor:
A. Is an intrinsic ion channel containing
receptor
B. Mediates neuronal depolarization
C. Is insensitive to blockade by bicuculline
D. Regulates intracellular cAMP

1 Answer

Answer :

C. Is insensitive to blockade by bicuculline

Related questions

Description : Receptors perform the following function/functions: A. Ligand recognition B. Signal transduction C. Both ligand recognition and signal transduction D. Disposal of agonists and antagonists

Last Answer : D. Disposal of agonists and antagonists

Description : The following receptor type has 7 helical membrane spanning amino acid segments with 3 extracellular and 3 intracellular loops: A. Tyrosine protein kinase receptor B. Gene expression regulating receptor C. Intrinsic ion channel containing receptor D. G protein coupled receptor

Last Answer : D. G protein coupled receptor

Description : Features of µ (Mu) opioid receptor include the following except: A. Acts by inhibiting cAMP formation B. Mediates miotic action C. Mediates low ceiling respiratory depression D. Mediates high ceiling supraspinal analgesia

Last Answer : C. Mediates low ceiling respiratory depression

Description : The following receptor has an intrinsic ion channel: A. Histamine H1 receptor B. Histamine H2 receptor C. Adrenergic alfa receptor D. GABA-benzodiazepine receptor

Last Answer : D. GABA-benzodiazepine receptor

Description : The following drugs exert their action through the GABAA-benzodiazepine–receptor Cl¯ channel complex except: A. Baclofen B. Zolpidem C. Bicuculline D. Phenobarbitone

Last Answer : A. Baclofen

Description : e primary mechanism by which general anaesthetics produce their action is: A. Affecting receptor operated ion channels in cerebral neurones B. Blocking voltage sensitive Na+ channels in neuronal ... activity of cerebral neurones D. Blocking production of high energy phosphates in the brain

Last Answer : A. Affecting receptor operated ion channels in cerebral neurones

Description : Agonist induced autophosphorylation, internalization and down regulation is a distinctive feature of: A. G-protein coupled receptors B. Intrinsic ion channel containing receptors C. Tyrosine protein kinase receptors D. Receptors regulating gene expression

Last Answer : C. Tyrosine protein kinase receptors

Description : The following is not true of local anaesthetics: A. The local anaesthetic is required in the unionized form for penetrating the neuronal membrane B. The local anaesthetic approaches its receptor ... the resting state D. The local anaesthetic combines with its receptor in the ionized cationic form

Last Answer : C. The local anaesthetic binds to its receptor mainly when the Na+ channel is in the resting state

Description : Local anaesthetics block nerve conduction by: A. Blocking all cation channels in the neuronal membrane B. Hyperpolarizing the neuronal membrane C. Interfering with depolarization of the neuronal membrane D. Both ‘B’ and ‘C’ are correct

Last Answer : C. Interfering with depolarization of the neuronal membrane

Description : Anthelmintic action of piperazine is due to: A. Interference with ATP generation in the worm B. Blockade of glucose uptake by the worm C. Hyperpolarization of nematode muscle by GABA agonistic action D. Depolarization of nematode muscle by activating nicotinic receptors

Last Answer : C. Hyperpolarization of nematode muscle by GABA agonistic action

Description : The most probable mechanism of action of mebendazole is: A. Depolarization of membrane and spastic paralysis of the worm B. Hyperpolarization of membrane and flaccid paralysis of the worm C. Loss of ... inhibition of glucose uptake in the worm D. Tegument damage and leakage of contents of the worm

Last Answer : C. Loss of intracellular microtubules and inhibition of glucose uptake in the worm

Description : The receptor transduction mechanism with the fastest time-course of response effectuation is: A. Adenylyl cyclase-cyclic AMP pathway B. Phospholipase C-IP3: DAG pathway C. Intrinsic ion channel operation D. Protein synthesis modulation

Last Answer : C. Intrinsic ion channel operation

Description : The following receptor has an intrinsic ion channel: A. Histamine H1 receptor B. Histamine H2 receptor C. Adrenergic alfa receptor D. GABA-benzodiazepine receptor

Last Answer : D. GABA-benzodiazepine receptor

Description : Select the correct statement about benzodiazepines (BZDs): A. All BZDs facilitate GABA mediated Cl¯ influx into neurones B. Different BZDs exert the same degrees of hypnotic, anxiolytic and anticonvulsant ... at all neuronal sites D. The muscle relaxant action of BZDs is not blocked by flumazenil

Last Answer : A. All BZDs facilitate GABA mediated Cl¯ influx into neurones

Description : The insulin receptor is a: A. Ion channel regulating receptor B. Tyrosine protein kinase receptor C. G-protein coupled receptor D. None of the above

Last Answer : B. Tyrosine protein kinase receptor

Description : Agonist induced autophosphorylation, internalization and down regulation is a distinctive feature of: A. G-protein coupled receptors B. Intrinsic ion channel containing receptors C. Tyrosine protein kinase receptors D. Receptors regulating gene expression

Last Answer : C. Tyrosine protein kinase receptors

Description : Sodium valproate has been shown to: A. Prolong neuronal Na+ channel inactivation B. Attenuate ‘T’ type Ca2+ current in neurones C. Inhibit degradation of GABA by GABA-transaminase D. All of the above

Last Answer : D. All of the above

Description : The most probable mechanism of anticonvulsant action of phenytoin is: A. Facilitation of GABAergic inhibitory transmission B. Hyperpolarization of neurones C. Interaction with Ca2+ channels to promote Ca2+ influx D. Prolongation of voltage sensitive neuronal Na+ channel inactivation

Last Answer : D. Prolongation of voltage sensitive neuronal Na+ channel inactivation

Description : The β3 adrenoceptor differs from the other subtypes of β receptor in that it: A. Is not blocked by the conventional doses of propranolol B. Is located primarily in the heart C. Regulates blood sugar level D. Is not coupled to G proteins

Last Answer : A. Is not blocked by the conventional doses of propranolol

Description : The β 3 adrenoceptor differs from the other subtypes of β receptor in that it: A. Is not blocked by the conventional doses of propranolol B. Is located primarily in the heart C. Regulates blood sugar level D. Is not coupled to G proteins

Last Answer : A. Is not blocked by the conventional doses of propranolol

Description : All of the following subserve as intracellular second messengers in receptor mediated signal transduction except: A. Cyclic AMP B. Inositol trisphosphate C. Diacyl glycerols D. G proteins

Last Answer : D. G proteins

Description : A. It is a clonidine congener used in spasticity due to stroke or spinal injury B. It reduces muscle tone by activating GABAB receptors C. It inhibits release of excitatory amino-acids in spinal interneurones D. It reduces muscle spasms without producing weaknes

Last Answer : B. It reduces muscle tone by activating GABAB receptors

Description : hat is/are the consequence(s) of myocardial Na+ K+ ATPase inhibition by digoxin: A. Increased intracellular Na+ ion concentration B. Increased cytosolic Ca2+ ion concentration C. Increased intracellular K+ ion concentration D. Both ‘A’ and ‘B’ are correct

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

Description : Frequency dependent cardiac calcium channel blockade is exhibited by: A. Verapamil B. Nifedipine C. Felodipine D. Amlodipin

Last Answer : A. Verapamil

Description : yocardial Na+ channel blockade by lignocaine has the following characteristic: A. It blocks inactivated Na+ channels more than activated channels B. It blocks activated Na+ channels more than inactivated ... Na+ channels D. It produces more prominent blockade of atrial than ventricular Na+ channels

Last Answer : A. It blocks inactivated Na+ channels more than activated channels

Description : The principal action common to all class I antiarrhythmic drugs is: A. Na+ channel blockade B. K+ channel opening C. Depression of impulse conduction D. Prolongation of effective refractory period

Last Answer : A. Na+ channel blockade

Description : A resting nerve is relatively resistant to blockade by lignocaine compared to one which is repeatedly stimulated because: A. Lignocaine penetrates resting nerve membrane poorly B. Lignocaine binds ... promotes ionization of lignocaine D. Nodes of Ranvier are inaccessible in the resting state

Last Answer : B. Lignocaine binds more avidly to the inactivated Na+ chan

Description : The following drug has been used to stimulate respiratory and vasomotor centres as an expedient measure, because it has the least propensity to induce convulsions: A. Pentylenetetrazole B. Doxapram C. Bicuculline D. Amphetamine

Last Answer : B. Doxapram

Description : Select the drug that antagonises diazepam action noncompetitively: A. Adenosine B. Flumazenil C. Bicuculline D. Valproic acid

Last Answer : C. Bicuculline

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

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

Description : The mechanism of action of barbiturates differs from that of benzodiazepines in that they: A. Do not affect the GABA-benzodiazepine receptor-chloride channel complex B. Act as inverse agonists at the ... without affecting its life time D. Have both GABA-facilitatory as well as GABA-mimetic actions

Last Answer : D. Have both GABA-facilitatory as well as GABA-mimetic actions

Description : The distinctive features of fluoxetine compared to the typical tricyclic antidepressants include the following except: A. It is less likely to produce cardiac arrhythmias in overdose B. It infrequently ... suffering from chronic somatic illness D. It does not block neuronal uptake of biogenic amines

Last Answer : D. It does not block neuronal uptake of biogenic amines

Description : The primary mechanism of action of benzodiazepines is: A. Dopamine antagonism B. Adenosine antagonism C. Opening of neuronal chloride channels D. Facilitation of GABA-mediated chloride influx

Last Answer : D. Facilitation of GABA-mediated chloride influx

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

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

Description : Esmolol has the following features except: A. Rapidly developing, shortlasting β adrenergic blockade B. Cardioselectivity of action C. Intrinsic sympathomimetic activity D. Suitability for intraoperative use

Last Answer : C. Intrinsic sympathomimetic activity

Description : Esmolol has the following features except: A. Rapidly developing, shortlasting β adrenergic blockade B. Cardioselectivity of action C. Intrinsic sympathomimetic activity D. Suitability for intraoperative use

Last Answer : C. Intrinsic sympathomimetic activity

Description : The most significant feature of the antiarrhythmic action of lignocaine is: A. Suppression of phase-4 depolarization in ventricular ectopic foci B. Prolongation of action potential duration C. Prolongation of effective refractory period D. Depression of membrane responsiveness

Last Answer : A. Suppression of phase-4 depolarization in ventricular ectopic foci

Description : The antiarrhythmic drug which decreases both rate of depolarization (phase 0) as well as rate of repolarization (phase 3) of myocardial fibres is: A. Lignocaine B. Propranolol C. Quinidine D. Verapamil

Last Answer : C. Quinidine

Description : The electrophysiological effects of digitalis on Purkinje fibres include the following except: A. Enhancement of resting membrane potential B. Decrease in the slope of phase-0 depolarization C. Increase in the rate of phase-4 depolarization D. Abbreviation of action potential duration

Last Answer : A. Enhancement of resting membrane potential

Description : Which anthelmintic drug acts through a specific glutamate gated Cl– ion channel found only in nematodes: A. Ivermectin B. Niclosamide C. Pyrantel pamoate D. Praziquantel

Last Answer : A. Ivermectin

Description : At the muscle end-plate, d-tubocurarine reduces the: A. Number of Na+ channels B. Duration for which the Na+ channels remain open C. Ion conductance of the open Na+ channel D. Frequency of Na+ channel opening

Last Answer : D. Frequency of Na+ channel opening

Description : Gram negative organisms are largely insensitive to benzyl penicillin because: A. They produce large quantities of penicillinase B. They do not utilise D-alanine whose incorporation in the cell wall is inhibited ... multilayer cell wall of gram negative bacteria D. Both A' and B' are correct

Last Answer : . Benzyl penicillin is not able to penetrate deeper into the lipoprotein-peptidoglycan multilayer cell wall of gram negative bacteria

Description : That sulfonamides act by inhibiting folate synthesis in bacteria is supported by the following findings except: A. Paraaminobenzoic acid antagonises the action of sulfonamides B. Methionine antagonises ... . Bacteria that utilise folic acid taken up from the medium are insensitive to sulfonamides

Last Answer : B. Methionine antagonises the action of sulfonamides

Description : Which of the following will result from blockade of H2 receptors? (a) Decreased camp in cardiac muscle (b) Increased camp in cardiac muscle (c) Decreased IP3 in gastric mucosa (d) Increased IP3 in gastric mucosa (e) Increased IP3 in smooth muscle

Last Answer : Ans: A

Description : The following is not true of quinidine: A. It blocks myocardial Na+ channels primarily in the open state B. It has no effect on myocardial K+ channels C. It produces frequency dependent blockade of myocardial Na+ channels D. It delays recovery of myocardial Na+ channels

Last Answer : B. It has no effect on myocardial K+ channels

Description : Select the opioid antagonist that is preferred for long term opioid blockade therapy of post addicts: A. Nalorphine B. Naloxone C. Naltrexone D. Nalbuphine

Last Answer : C. Naltrexone

Description : Adaptive changes in brain monoamine turnover due to blockade of noradrenaline/5-HT reuptake is credited with the following effect: A. Antipsychotic B. Antianxiety C. Antiparkinsonian D. Antidepressant

Last Answer : D. Antidepressant

Description : Epidural anaesthesia differs from spinal anaesthesia in that: A. Epidural anaesthesia produces less cardiovascular complications B. Headache is more common after epidural anaesthesia C. Blood ... . Greater separation between sensory and motor blockade can be obtained with epidural anaesthes

Last Answer : D. Greater separation between sensory and motor blockade can be obtained with epidural anaesthesia