Description : Cyclo-oxygenase is involved in the synthesis of (A) Prostaglandins (B) Thromboxanes (C) Both (A) and (B) (D) None of these
Last Answer : Answer : C
Description : Anti-inflammatory corticosteroids inhibit the synthesis of (A) Leukotrienes (B) Prostaglandins (C) Thromboxanes (D) All of these
Last Answer : Answer : D
Description : True statements regarding eicosanoids include which of the following? A. Prostaglandins and thromboxanes are synthesized via the cyclo-oxygenase pathway. B. The vasoconstricting, platelet-aggregating, ... prostaglandins have a short circulation half-life and exert most of their effects locally.
Last Answer : Answer: ABD DISCUSSION: The eicosanoids are a group of compounds arising from the metabolism of arachidonic acid. The prostaglandins and thromboxanes are synthesized via the cyclo-oxygenase ... effects and may be involved in the physiologic responses associated with anaphylactic and septic shock
Description : Slow reacting Substance of Anaphylaxis is a mixture of (A) Prostaglandins (B) Prostacyclins (C) Thromboxanes (D) Leukotrienes
Description : Prostaglandins are inactivated by (A) 15-Hydroxyprostaglandin dehydrogenase (B) Cyclo-oxygenase (C) Lipo-oxygenase (D) None of these
Last Answer : Answer : A
Description : Eicosanoids mediate inflammation in a variety of ways. Of the following statements, which are true with regard to this? a. Eicosanoids are stored in cytoplasmic granules ... include vasodilatation, vasoconstriction, increased vascular permeability and both chemotaxis and chemoattractant inhibition
Last Answer : Answer: b, d The eicosanoids are derived from arachidonic acid (eicosatetraenoic acid) and consist of prostaglandins, thromboxanes, leukotrienes and lipoxins. The eicosanoids are not ... nervous system d. Mononuclear phagocytes release a variety of proinflammatory cytokines and growth factors
Description : Aspirin blocks the synthesis of (A) Prostaglandins only (B) Prostacyclins only (C) Thromboxanes only (D) All of these
Description : Cyclooxygenase-1 and –2 are responsible for (a) The synthesis of prostaglandins from arachidonate (b) The synthesis of leukotrienes from arachidonate (c) The conversion of ATP to cAMP (d) The metabolic degradation of cAMP (e) The conversion of GTP to cGMP
Last Answer : Ans: A
Description : Anti-inflammatory corticosteroids inhibit (A) Phospholipase A1 (B) Phospholipase A2 (C) Cyclo-oxygenase (D) Lipo-oxygenase
Last Answer : Answer : B
Description : Phenylbutazone and indomethacin inhibit (A) Phospholipase A1 (B) Phospholipase A2 (C) Cyclo-oxygenase (D) Lipo-oxygenase
Description : Which of the following is used for inducing labour? (A) Prostaglandins (B) Prostacyclins (C) Vasopressin (D) Thromboxanes
Description : Inflammation is a complex tissue reaction that includes the release of cytokines, leukotrienes, prostaglandins, and peptides. Prostaglandins involved in inflammatory processes are produced from arachidonic acid by (a) ... 2 (c) Glutathione - S - transferase (d) Lipoxygenase (e) Phospholipase A2
Last Answer : Ans: B
Description : Explain in brief about leukotrienes and prostaglandins Leukotrienes and prostaglandins are formed only when the mast cell undergo degranulation and enzymatic break down of phospholipids in the plasma membrane ?
Last Answer : The effects produced by them are more pronounced and long lasting than histamine. Leukotrienes mediate mucous production and bronchoconstriction. Prostaglandin D2 causes bronchoconstriction.
Description : There are no preformed stores of the following autacoid/autacoids: A. Prostaglandins B. Leukotrienes C. Angiotensin II D. All of the above
Last Answer : D. All of the above
Description : A cup of strong coffee would be expected to (A) Interfere with synthesis of prostaglandins (B) Decrease the effects of Glucagon (C) Enhance the effects of epinephrine (D) Provide the vitamin nicotinic acid
Description : A cup of strong coffee would be expected to (A) Interfere with the synthesis of prostaglandins (B) Decrease the effect of glucagon (C) Enhance the effect of epinephrine (D) Provide the vitamin nicotinic acid
Description : From arachidonate, synthesis of prostaglandins is catalysed by (A) Cyclooxygenase (B) Lipoxygenase (C) Thromboxane synthase (D) Isomerase
Description : Synthesis of prostaglandins is inhibited by (A) Glucocorticoids (B) Aspirin (C) Indomethacin (D) All of these
Description : For synthesis of prostaglandins, the essential fatty acids give rise to a fatty acid containing (A) 12 carbon atoms (B) 16 carbon atoms (C) 20 carbon atoms (D) 24 carbon atoms
Description : Thromboxanes cause (A) Vasodilation (B) Bronchoconstriction (C) Platelet aggregation (D) All of these
Description : .Which of these is not an important component of initiation of parturition in humans? (a) Release of oxytocin (b) Release of prolactin (c) Increase in estrogen and progesterone ratio (d) Synthesis of prostaglandins
Last Answer : b) Release of prolactin
Description : The enzyme catalyzing conversion of androstenedione to testosterone is a (A) Oxygenase (B) Dehydrogenase (C) Isomerase (D) Decarboxylase
Description : Microsomal hydroxylase system contains a (A) Di-oxygenase (B) Mono-oxygenase (C) Both (A) and (B) (D) None of thse
Description : Isocitrate dehydrogenases is (A) Aerobic dehydrogenase (B) Anaerobic dehydrogenase (C) Hydroperoxidase (D) Oxygenase
Description : Name the enzyme that acts both as carboxylase at one time and oxygenase at another time. (A) PEP carboxylase (B) RuBP carboxylase (C) Carbonic anyhdrase (D) None of these
Description : In which of the following types of enzymes, water may be added to a C—C double bond without breaking the bond? (A) Hydrolase (B) Hydratase (C) Hydroxylase (D) Oxygenase
Description : Tryptophan pyrolase is currently known as (A) Tryptophan deaminase (B) Tryptophan dioxygenase (C) Tryptophan mono oxygenase (D) Tryptophan decarboxylase
Description : An enzyme which uses hydrogen acceptor as substrate is (A) Xanthine oxidase (B) Aldehyde oxidase (C) Catalase (D) Tryptophan oxygenase
Description : β-Carotene, precursor of vitamin A, is oxidatively cleaved by (A) β-Carotene dioxygenase (B) Oxygenase (C) Hydroxylase (D) Transferase
Description : Leukotrienes cause (A) Increase in capillary permeability (B) Aggregation of platelets (C) Bronchodilatation (D) None of these
Description : Leukotrienes: 1) Are formed from the cyclooxygenase pathway 2) Are synthesized by fibroblasts 3) Decrease vascular permeability 4) Leukotriene D4 has been identified as SRS-A which causes bronchial wall smooth muscle relaxation 5) Stimulate mucus secretion
Last Answer : Answers-5 Leukotrienes are synthesized by leucocytes.They are mediators of allergic reaction. They increase vascular permeability and attract neutrophils and eosinophils to inflammatory sites. ... stimulate mucus production, an important consideration in the pathophysiology of bronchial asthma.
Description : What is the precursor of leukotrienes?
Last Answer : They are produced from arachidonic acid.
Description : LCAT activity is associated with which of the lipo-protein complex? (A) VLDL (B) Chylomicrones (C) IDL (D) HDL
Description : The activity of kinins is modulated by (A) Prostaglandins (B) Ca++ (C) Increased cAMP level (D) Increased cGMP level
Description : Which one of the following hormones is derived most completely from tyrosine? (A) Glucagon (B) Thyroxine (C) Insulin (D) Prostaglandins
Description : The suffix number in the names of prostaglandins gives the number of (A) OH groups (B) Double bonds (C) Acid groups (D) Ketoacids
Description : Which of tne of the following scientists has not worked in the field of prostaglandins? (A) Voneuler (B) Sultan Karim (C) Andre robet (D) Kendal
Description : Prostaglandins are (A) C2 unsaturated acids (B) C27 saturated alcohols (C) C20 saturated acids (D) C27 saturated alcohols
Description : Which of the following property of prostaglandins has been utilized by chinicians in hospital for (A) Inducing fever (B) Causing inflammation (C) Effecting smooth muscle contraction (D) Disaggregation of spermatozoa
Description : Richest source of prostaglandins in a human male is (A) Blood (B) Urine (C) Semen (D) C.S.F.
Description : Cholesterol is the precursor for the biosynthesis of (A) fatty acid (B) prostaglandins (C) bile acids (D) sphingmyelin
Description : Acrolein Test is positive for (A) Glycerol (B) Prostaglandins (C) Carbohydrates (D) Proteins
Description : All the following are functions of prostaglandins except (A) Lowering of B.P (B) Introduction of labour (C) Anti inflammatory (D) Prevention of myocardial infraction
Description : Prostaglandins are synthesized in the body from (A) Myristic acid (B) Arachidonic acid (C) Stearic acid (D) Lignoceric acid
Description : All active prostaglandins have atleast one double bond between positions: (A) 7 and 8 (B) 9 and 10 (C) 11 and 12 (D) 13 and 14 FATS AND FATTY ACID METABOLISM 95
Description : Prostaglandins have a common structure based on prostanoic acid which contains carbon atoms: (A) 12 (B) 16 (C) 18 (D) 20
Description : Prostaglandins are liberated in the circulation by the stimulation of (A) Anterior pituitary glands (B) Posterior pituitary glands (C) Adrenal gland (D) Thyroid gland
Description : The prostaglandins are synthesized from (A) Arachidonic acid (B) Oleic acid (C) Linoleic acid (D) Linolenic acid
Description : Prostaglandins decrease all of the following except (A) Gastric acid secretion (B) Blood pressure (C) Uterine contraction (D) Platelet aggregation
Description : Prostaglandins stimulate (A) Aggregation of platelets (B) Lipolysis in adipose tissue (C) Bronchodilatation (D) Gastric acid secretion