ENZYMES, GROWTH FACTORS, PROTEINS, AND RECEPTORS

HMG CoA reductase

Which rate limiting and regulatory enzyme for cholesterol synthesis converts HMG CoA to Mevalonate?

Cyclooxygenase enzymes, COX-1 and COX-2

Which enzymes convert arachidonic acid to thromboxane A2 (TXA2)?

COX-1 and COX-2

Which two enzymes are irreversibly inhibited by aspirin?

COX-2

Which enzyme is inhibited by other NSAIDs for anti-inflammatory purposes?

Phosphodiesterase (PDE)

Which enzyme is inhibited by dipyridamole and cilostazol to increase cAMP, reduce calcium, and inhibit platelet activation?

Antithrombin III

Which protein is activated by Heparin and Low Molecular Weight Heparin (LMWH) to inhibit Factor X and partly inhibit thrombin?

Thrombin

Which enzyme is mostly inhibited by Antithrombin III, and partly by Heparin?

Factor X

Which enzyme is mostly inhibited by Antithrombin III and LMWH?

Thrombin

Which enzyme converts prothrombin to thrombin and catalyzes the conversion of fibrinogen into fibrin?

Factor X and V

Which two coagulation factors are activated in the final common pathway of coagulation to catalyze the conversion of prothrombin to thrombin?

Plasminogen

Which protein is activated by fibrinolytic agents to become plasmin?

Plasmin

Which enzyme, activated from plasminogen, degrades fibrin (cuts fibrin) to dissolve clots?

Protein C, Protein S, and Antithrombin III

Which three natural anticoagulants dissolve clots, alongside plasmin?

Plasmin

Which enzyme degrades both fibrin and fibrinogen if present in numerous amounts?

Tissue factor

Which protein, together with Factor VIIa, immediately activates Factor X to provide a thrombin burst?

Lecithin-cholesterol acyltransferase (LCAT)

Which enzyme esterifies free cholesterol from macrophages and other peripheral cells to be taken up by the liver in the reverse cholesterol transport pathway?

Cholesteryl Ester Transfer Protein (CETP)

Which protein transfers HDL cholesterol esters to VLDL and chylomicrons for eventual liver uptake and excretion?

LDL receptor

Which protein recognizes chylomicron remnants via ApoE for clearance by the liver?

Lipoprotein lipase (LPL)

Which enzyme hydrolyzes chylomicrons to strip off triglycerides, converting them to chylomicron remnants?

Lipoprotein lipase (LPL)

Which enzyme hydrolyzes VLDL in the endogenous pathway, stripping off triglycerides for storage and energy?

Hepatic lipase (HL9)

Which enzyme further hydrolyzes the remainder of IDL not removed by the liver, converting it to LDL?

LDL receptor

Which protein interacts with ApoB-100 to remove 70% of LDL from the circulation by endocytosis by the liver?

Neimann-Pick C1-Like 1 (NPC1L1)

Which transport protein is the target of ezetimibe, responsible for intestinal cholesterol capture and absorption of phytosterols?

ApoB-100

Which apolipoprotein is targeted by Mipomersen, triggering selective degradation of the molecule to reduce atherogenic lipids?

ATP citrate lyase

Which enzyme is inhibited by Bempedoic acid in the HMG CoA reductase pathway to hinder cholesterol synthesis?

Thrombin

Which coagulation factor undergoes positive feedback, activating more prothrombin, platelets, and catalyzing fibrinogen to fibrin conversion?

Factor X, IX, VII, and II

What four coagulation factors, which are vitamin K-dependent, are inhibited in synthesis by Vitamin K antagonists (Warfarin)?

Factor X

Which coagulation factor is inhibited by Fondaparinux, which binds and activates antithrombin III?

Alpha adrenergic receptor

What type of receptor is blocked by Quinidine, causing vasodilation and a reflex increase in the sinus node rate?

Factor VIII

Which coagulation factor is released from the endothelium by Desmopressin (Vasopressin or ADH)?

Factor VIII and IX

Which two coagulation factors are supplied by intravenous injection for patients with hemophilia?

Recombinant Factor VIIA (rFVIIa)

Which protein provides a thrombin burst by activating Factor X together with tissue factor?

Plasminogen

Which protein's activation is competitively inhibited by epsilon Aminocaproic Acid and Tranexamic Acid?

Antithrombin III

Which natural anticoagulant is activated by Fondaparinux, a synthetic analogue of its activating sequence?

Prothrombin

Which coagulation factor is partly inhibited by Heparin?

Prothrombin Complex Concentrate

What complex concentrate, when activated (aPCC), provides activated clotting factors (II, V, X) to bypass missing factors like VIII or IX?

Factor X

Which coagulation factor is directly inhibited by Rivaroxaban, Apixaban, and Edoxaban?

Thrombin

Which enzyme is directly inhibited by Argatroban, Bivalirudin, and Dabigatran?

Proprotein convertase subtilisin/kexin type 9 (PCSK9)

Which protein, produced by hepatocytes, binds to the LDL receptor, causing lysosomal degradation and reduced LDL receptor expression on the cell membrane?

Microsomal triglyceride transfer protein (MTP)

Which protein is essential in the addition of triglycerides in nascent VLDL in the liver and chylomicrons in the intestine?

Bone Morphogenetic Protein Receptor Type 2 (BMPR2) signaling pathway

What signaling pathway mutation causes familial pulmonary hypertension?

BMPR2

What cell surface protein binds cytokines including TGF-beta, BMP, activin, and inhibin?

Factor VIII

Which coagulation factor, when missing, is targeted for replacement by the Factor Eight Inhibitor Bypassing Agent (FEIBA)?

Andexanet alpha (a synthetic Factor X)

Which synthetic protein reverses the effects of Factor Xa inhibitors like Rivaroxaban, Apixaban, and Edoxaban?

Idarucizumab

Which monoclonal antibody binds Dabigatran to reverse its effects?

Prothrombin

Which protein is converted to thrombin by Factor X and V?

Fibrinogen

Which protein is linked by GPIIb/IIIa receptors between different platelets?

Prostaglandins

Which molecules protect the stomach lining, and whose synthesis is inhibited by aspirin and NSAIDS, leading to GI upset?

Apolipoproteins (or apoproteins)

Which proteins surround the hydrophobic core of lipoproteins and are involved in structural basis, receptor ligand, and enzyme activation?

ApoB

Which major apolipoprotein group is generally associated with "bad particles" (pro-atherogenic lipoproteins)?

ApoA

Which major apolipoprotein group is attached to the good cholesterol, HDL?

ApoA-I and ApoA-II

Which two specific apolipoproteins are attached to HDL?

ApoB-48

Which apolipoprotein is attached to chylomicrons, synthesized in the intestine?

ApoB-100

Which apolipoprotein is attached to VLDL, IDL, or LDL, synthesized in the liver?

ApoB-100

Which apolipoprotein serves as the ligand for the LDL receptor in the liver for LDL removal?

ApoB

Which apolipoprotein's decreased secretion is a mechanism of action of omega fatty acids?

ApoC-III

Which apolipoprotein's reduced expression by fibrates enhances the clearance of VLDL remnants?

ApoA-I and ApoA-II

Which two apolipoproteins' expression is stimulated by PPAR-alpha, leading to increased HDL?

PPAR-alpha (PPAR activators)

Which nuclear transcription receptor is activated by Fibric Acid Derivatives (fibrates) to stimulate fatty acid oxidation and lipoprotein lipase synthesis?

LDL Receptors (LDL-R)

Which receptors are upregulated on the liver when hepatic cholesterol synthesis is reduced by statins?

LDL Receptors

Which receptors recognize ApoB-100 and ApoE-rich lipoproteins, leading to enhanced clearance of LDL precursors?

Apo A1 transcription

Which factor is regulated by statins, leading to a slight increase in HDL?

Scavenger receptor B1 (SR-B1)

Which receptor's activation in the liver allows selective uptake of HDL cholesterol esters?

ADP

Which molecule's binding to receptors on platelets is inhibited by Thienopyridines (e.g., Clopidogrel, Prasugrel)?

Glycoprotein Ia and Ib (GP Ia and Ib)

Which receptors on platelet surfaces are involved in platelet attachment to the vessel wall via von Willebrand Factor?

Glycoprotein IIB/IIIA (GPIIb/IIIa)

Which platelet receptors serve as the point of attachment and linkage for fibrinogen to crosslink two platelets together?

GPIIb/IIIa

Which receptors are blocked by Abciximab, Eptifibatide, and Tirofiban to inhibit crosslinking by fibrinogen between platelets?

Von Willebrand Factor (vWF)

Which protein facilitates the attachment of platelets to the vessel wall?

Factor VIII

Which coagulation factor is protected by von Willebrand Factor (vWF), making desmopressin useful for mild hemophilia?

Prothrombin Complex Concentrate (aPCC)

What drug provides activated clotting factors (II, V, X) to bypass the need for missing factors (VIII or IX)?

Protein C

Which anticoagulant protein's synthesis is inhibited by Warfarin (a Vitamin K antagonist), leading initially to a prothrombotic effect?

Tumor Necrosis Factor (TNF), Interleukin-1 (IL-1), and Interleukin-8 (IL-8)

Which three cytokines, released by macrophages, activate neutrophils?

Transforming Growth Factor beta (TGF-beta) and platelet derived growth factor (PDGF)

What two macrophage derived fibrogenic cytokines signal cytoplasmic growth and collagen deposition associated with the healing phase of injury?

Nuclear factor kappa B (NF-kB)

Which transcription factor's activation shifts the balance in favor of a pro-inflammatory state in ARDS?

Adenosine receptor blockers

What type of drugs are Theophylline and Caffeine, which interact with Adenosine?

Adenosine uptake inhibitor

What type of drug is Dipyridamole, which interacts with Adenosine?

Factor Xa

What specific coagulation factor is inhibited by Low Molecular Weight Heparin (LMWH) after activating Antithrombin III?

Calcium channels

Which channels are blocked by Class IV antiarrhythmic drugs (Verapamil and Diltiazem)?

Potassium channels

Which channels are blocked by Class III antiarrhythmic drugs (Amiodarone, Sotalol) to prolong the effective refractory period (ERP)?

Sodium channels

Which channels are blocked by Class I antiarrhythmic drugs (Quinidine, Lidocaine) to reduce Phase 0 depolarization?

Sodium channels

Which ion's influx causes rapid depolarization (Phase 0) in cardiac muscle action potential?

Potassium channels

Which ion's efflux causes repolarization (Phase 3) in both cardiac muscle and pacemaker cell action potentials?

Calcium channels

Which ion's influx causes the plateau (Phase 2) in cardiac muscle action potential and rapid depolarization (Phase 0) in pacemaker cell action potential?

Na+/K+ ATPase, Sodium channels, Potassium channels, and Calcium channels

Which four components are influenced by Magnesium in its role as a membrane stabilizer?

Potassium channels

Which channels are normalized by Potassium therapy, correcting the K+ gradients and pools in the body?

Potassium channels

Which channels are blocked by Quinidine to slow repolarization and lengthen the Action Potential Duration (APD)?

Sodium channels

Which channel is affected by Quinidine with an intermediate interaction?

Sodium channel

Which channel is affected by Lidocaine with a rapid interaction, acting exclusively to suppress electrical activity of depolarized tissue?

Sodium channels and Potassium channels

Which two channels are blocked by Flecainide, although it is mainly known as a sodium channel blocker?

Calcium channels

Which channels are weakly blocked by Amiodarone?

Beta adrenoreceptors

Which receptors are non-competitively inhibited by Amiodarone?

Alpha and Beta adrenoreceptors

Which two receptors' noncompetitive blocking properties contribute to the antianginal effects of Amiodarone?

Calcium channels

Which channels' influx in the vascular smooth muscle is blocked by Amiodarone, contributing to perivascular dilation?

Calcium channels

Which channels are blocked by Verapamil (both activated and inactivated)?

Proprotein convertase subtilisin/kexin type 9 (PCSK9)

Which protein's messenger RNA (mRNA) is targeted by Inclisiran to inhibit synthesis, preventing LDL receptor degradation?

Factor Xa

Which coagulation factor's inhibitors are reversed by Andexanet alpha (a synthetic Factor X)?

Factor X

Which activated clotting factor is supplied by Factor Eight Inhibitor Bypassing Agent (FEIBA) and Activated Prothrombin Complex Concentrate (aPCC), along with Factor II and V?

Factor V

Which activated clotting factor is supplied by FEIBA and aPCC, along with Factor II and X?

Factor II

Which activated clotting factor is supplied by FEIBA and aPCC, along with Factor V and X?

Protein C

Which protein is depleted by Warfarin, which causes an initial prothrombotic effect?