Description : The following serotonergic receptor functions primarily as an autoreceptor on neurones: A. 5-HT1A B. 5-HT2A C. 5-HT3 D. 5-HT4
Last Answer : A. 5-HT1A
Description : Activation of the following type of receptors present on myenteric neurones by metoclopramide is primarily responsible for enhanced acetylcholine release improving gastric motility: A. Muscarinic M1 B. Serotonergic 5-HT3 C. Serotonergic 5-HT4 D. Dopaminergic D2
Last Answer : C. Serotonergic 5-HT4
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 : Which of the following is a G protein coupled receptor: A. Muscarinic cholinergic receptor B. Nicotinic cholinergic receptor C. Glucocorticoid receptor D. Insulin receptor
Last Answer : A. Muscarinic cholinergic receptor
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 : Cisapride enhances gastrointestinal motility by: A. Activating serotonin 5-HT4 receptor B. Activating muscarinic M3 receptor C. Blocking dopamine D2 receptor D. All of the above
Last Answer : A. Activating serotonin 5-HT4 receptor
Description : Olanzapine has the following features except: A. It is an antipsychotic drug with weak D2 receptor blocking action B. It has potent 5-HT2 blocking and antimuscarinic actions C. It lowers seizure threshold D. It produces prominent extrapyramidal side effects
Last Answer : D. It produces prominent extrapyramidal side effect
Description : What is true of risperidone: A. It is an atypical neuroleptic which produces few extrapyramidal side effects B. It has combined dopamine D2 and 5-HT2 receptor blocking activity C. It does not cause hyperprolactinemia D. Both 'A' and 'B' are correct
Last Answer : D. Both 'A' and 'B' are correct
Description : Compared to other antipsychotic drugs, the distinctive feature of penfluridol is: A. Very long duration of action B. Weak dopamine D2 blocking activity C. Lack of extrapyramidal side effects D. Additional 5-HT2 receptor blocking activity
Last Answer : A. Very long duration of action
Description : The most important receptor involved in cytotoxic drug induced vomiting is: A. Histamine H1 receptor B. Serotonin 5-HT3 receptor C. Dopamine D2 receptor D. Opioid μ receptor
Last Answer : B. Serotonin
Description : The following action of 5-Hydroxy tryptamine is mediated by the 5-HT3 receptor: A. Vasoconstriction B. Bradycardia C. EDRF release D. Platelet aggregation
Last Answer : B. Bradycardia
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
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 : The following statement about histamine is not correct: A. It is the sole mediator of immediate hypersensitivity reaction B. It plays no role in delayed hypersensitivity reaction C. It serves as a neurotransmitter in the brain D. All types of histamine receptors are G protein coupled receptors
Last Answer : A. It is the sole mediator of immediate hypersensitivity reaction
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 dopamine D2 receptor has the following feature: A. It is excitatory in nature B. It is negatively coupled to adenyl cyclase C. It is selectively blocked by bromocriptine D. It is not blocked by metoclopramide
Last Answer : B. It is negatively coupled to adenyl cyclase
Description : The following is a selective 5-HT4 agonist: A. Buspirone B. Sumatriptan C. Cisapride D. Clozapine
Last Answer : C. Cisapride
Description : Actions of 5-HT2 receptor activation are primarily mediated by: A. Increased membrane permeability to Na+ ions B. Increased formation of cAMP C. Activation of guanylyl cyclase D. Generation of inositol trisphosphate and diacyl glycerols
Last Answer : D. Generation of inositol trisphosphate and diacyl glycerols
Description : The most important receptor involved in cytotoxic drug induced vomiting is (a) Histamine H1 receptor (b) Serotonin 5-HT3 receptor (c) Dopamine D2 receptor (d) Opioid µ receptor
Last Answer : Ans: B
Description : The action of 5-Hydroxy tryptamine mediated by the 5-HT3 receptor is (a) Vasoconstriction (b) Bradycardia (c) EDRF release (d) Platelet aggregation
Description : The following antipsychotic drug has weak dopamine D2 but additional 5-HT2 blocking activity and benefits both positive and negative symptoms of schizophrenia: A. Loxapine B. Clozapine C. Pimozide D. Penfluridol
Last Answer : B. Clozapin
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
Description : Select the prokinetic-antiemetic drug which at relatively higher doses blocks both dopamine D2 as well as 5-HT3 receptors and enhances acetylcholine release from myenteric neurones: A. Cisapride B. Prochlorperazine C. Metoclopramide D. Domperidon
Last Answer : C. Metoclopramide
Description : Metoclopramide blocks apomorphine induced vomiting, produces muscle dystonias and increases prolactin release indicates that it has: A. Anticholinergic action B. Antihistaminic action C. Anti 5-HT3 action D. Antidopaminergic action
Last Answer : D. Antidopaminergic action
Description : The following is a selective 5-HT1D receptor agonist: A. Buspirone B. Ondansetron C. Sumatriptan D. α-methyl 5-HT
Last Answer : C. Sumatriptan
Description : Venlafaxine differs from standard tricyclic antidepressants in that it: A. Does not inhibit 5-HT reuptake B. Does not inhibit noradrenaline reuptake C. Does not have anticholinergic or antiadrenergic property D. Has lower antidepressant efficacy
Last Answer : C. Does not have anticholinergic or antiadrenergic property
Description : The following antidepressant increases rather than inhibits 5-HT uptake into neurones: A. Clomipramine B. Fluoxetine C. Tianeptine D. Trazodone
Last Answer : C. Tianeptine
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 : 5-HT appears to play a role in the following except: A. Regulation of normal BP B. Regulation of intestinal peristalsis C. Haemostasis D. Causation of migraine
Last Answer : A. Regulation of normal BP
Description : The typical response to intravenous injection of 5-HT in an anaesthetised animal is: A. Rise in BP B. Fall in BP C. Rise followed by brief fall in BP D. Transient fall, followed by brief rise, followed by prolonged fall in BP
Last Answer : D. Transient fall, followed by brief rise, followed by prolonged fall in BP
Description : Agonists affect the receptor molecule in the following manner: A. Alter its amino acid sequence B. Denature the receptor protein C. Alter its folding or alignment of subunits D. Induce covalent bond formation
Last Answer : C. Alter its folding or alignment of subunits
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 : a1 – receptors are coupled with _______ G protein. (a) Gs (b) Gi (c) Gq (d) Go
Last Answer : Ans: C
Description : Which one of the following drugs does NOT act through G-Protein coupled receptors? (A) Epinephrine (B) Insulin (C) Dopamine (D) TSH
Last Answer : (B) Insulin
Description : The success of oral rehydration therapy of diarrhoea depends upon the following process in the intestinal mucosa: A. Sodium pump mediated Na+ absorption B. Glucose coupled Na+ absorption C. Bicarbonate coupled Na+ absorption D. Passive Na+ diffusion secondary to nutrient absorption
Last Answer : B. Glucose coupled Na+ absorption
Description : Phosphorylated IRS-1 activates GRB-2 which is (A) G-protein receptor binding protein-2 (B) Growth factor receptor binding protein-2 (C) Growth hormone receptor binding protein-2 (D) Glucocorticoid receptor binding protein-2 226 MCQs IN BIOCHEMISTRY
Last Answer : Answer : B
Description : Which of the following statement(s) is/are true concerning cell membrane receptors? a. The largest family of cell surface receptors are the G-protein-linked receptors b. Activities of the ... through the use adenylate cyclase d. Tyrosine kinase receptors are considered G-protein-linked receptors
Last Answer : Answer: a, c All water-soluble regulatory molecules bind to the cell surface receptor proteins. Binding of the appropriate ligand evokes an intracellular signal which usually regulates ... are adenylate cyclase, which converts ATP to cAMP, and the polyphosphoinositide-specific phospholipase C
Description : The plasma half life of penicillin-G is longer in the new born because their: A. Plasma protein level is low B. Drug metabolizing enzymes are immature C. Glomerular filtration rate is low D. Tubular transport mechanisms are not well developed
Last Answer : D. Tubular transport mechanisms are not well developed
Description : What is true of docetaxel: A. It is used as a reserve drug for refractory breast and ovarian cancer B. It is a selective estrogen receptor modulator used for breast cancer C. It is effective only in estrogen receptor positive breast cancer D. Both 'B' and 'C' are correct
Last Answer : A. It is used as a reserve drug for refractory breast and ovarian cancer
Description : Choose the correct statement about ondansetron: A. It is a dopamine D2 receptor antagonist B. It suppresses postoperative nausea and vomiting C. It is the most effective antiemetic for motion sickness D. It is not effective by oral route
Last Answer : B. It suppresses postoperative nausea and vomitin
Description : The fastest symptomatic relief as well as highest healing rates in reflux esophagitis are obtained with: A. Prokinetic drugs B. H2 receptor blockers C. Proton pump inhibitors D. Sodium alginate
Last Answer : C. Proton pump inhibitors
Description : Choose the correct statement about H2 receptor blockers: A. They are the most efficacious drugs in inhibiting gastric acid secretion B. They cause fastest healing of duodenal ulcers C. They prevent stress ulcers in the stomach D. They afford most prompt relief of ulcer pain
Last Answer : C. They prevent stress ulcers in the stomach
Description : In the intact animal H2 receptor antagonists potentiate the following action of histamine: A. Cardiac stimulation B. Fall in blood pressure C. Uterine relaxation D. Bronchospasm
Last Answer : D. Bronchospasm
Description : Select the hypolipidemic drug that enhances lipoprotein synthesis, fatty acid oxidation and LDLreceptor expression in liver through paroxisome proliferator-activated receptor α: A. Lovastatin B. Atorvastatin C. Bezafibrate D. Nicotinic acid
Last Answer : C. Bezafibrate
Description : The following is true of clopidogrel except: A. It is a GPIIb/IIIa receptor antagonist B. It inhibits fibrinogen induced platelet aggregation C. It is indicated for prevention of stroke in patients with transient ischaemic attacks D. It is a prodrug
Last Answer : A. It is a GPIIb/IIIa receptor antagonist
Description : Che following is true of desmopressin except: A. It is nonselective V1 and V2 receptor agonist B. It is more potent and longer acting than arginine vasopressin (AVP) C. It is preferred over AVP for treatment of diabetes insipidus D. It can be administered orally
Last Answer : A. It is nonselective V1 and V2 receptor agonist