click below
click below
Normal Size Small Size show me how
CVS Pharmacology
Cardiovascular system pharmacology-Ischemic Heart Disease
| Question | Answer |
|---|---|
| What is myocardial stunning? | The reversible reduction of function of heart contraction after reperfusion not accounted for by tissue damage or reduced blood flow |
| The calcium combines with calmodulin to form: | a complex that converts the enzyme myosin light-chain kinaseto its active form (MLCK) |
| Beta2 agonists may cause relaxation in smooth muscle by: | accelerating the inactivation of MLCK |
| Calcium influx is inhibited by | CCBs, leading to muscle relaxation |
| Organic nitrates release | Nitric oxide |
| What is the function of nitric oxide? | Activation of guanylyl cyclase and increases formation of cGMP |
| What is the function of cGMP? | Smooth muscle relaxation by activating kinases that increase myosin phosphatase activity and decrease myosin phosphate levels |
| α 1-Adrenoceptor agonists activate | phospholipase C (PLC) |
| What is the function Phospholipase C (PLC)? | Increased formation of inositol triphosphate (IP3) from phosphatidyl inositol bisphosphate(PIP2), leading to increased release of calcium from the sarcoplasmic reticulum |
| Function of B2 receptor agonists: | Increased formation of cyclic adenosine monophosphate (cAMP), which activates kinases that inhibit myosin light-chain kinase |
| What is the prototype of nitroglycerine? | Nitroglycerine |
| What is the function of Nitroglycerine? | Nonspecific smooth muscle relaxant General vasodilation |
| How is nitroglycerine administered? | Usually, sublingual But can be administered by many routes |
| Onset of action of nitroglycerine? | 1-3 minutes, Peaks at 10 minutes |
| DOA of nitroglycerine: | 15-30 minutes Until reductase in the liver breaks down the drug |
| How long does arteriolar vasodilation last? | 5-10 minutes |
| How long does venous vasodilation last? | 30 minutes |
| Function of arteriolar vasodilation: | Decreases systemic blood pressure (afterload) and causes reflex tachycardia and increased contractility (the last two are deleterious effects) Might increase MVO2 |
| Function of venous vasodilation: | Decreases venous return (preload) and decreases MVO2 |
| Side effects of Nitroglycerine: | Headache Hypotension Tachycardia Increased intraocular and intracranial pressures Methemoglobinemia Tolerance: only for the arteriolar effects Withdrawal: in workers in ammunition industry |
| Functions of Beta Adrenergic Blockers | Cause subjective and objective improvement Decreased number of anginal episodes Nitroglycerine consumption Enhanced exercise tolerance Improved ECG |
| Advantages of taking Beta adrenergic blockers: | Prevent actions of catecholamines, so more effective during exertion Do not dilate coronary arteries Do not increase collateral blood flow |
| Functions of CCBs: | Beneficial in vasospasm |
| Harmful effects of CCBs: | Can affect platelets aggregation May be dangerous in the presence of heart failure and in patients susceptible to hypotension |
| Side effects of CCBs: | Hypotension Headache Dizziness Flushing Peripheral edema. |
| Function of Dipyridamole: | Inhibits the uptake of adenosine and inhibits adenosine deaminase enzyme Thought to be a good coronary dilator Increases the blood flow to the normal area Still used as an antiplatelet drug |
| Other solutions for ischemic heart disease: | ACEI Anticoagulants and/or Thrombolytic Therapy Cholesterol Lowering Agents Angioplasty Surgery |
| Newer anti-anginal drugs: | Metabolic modulators Direct bradycardic agents Potassium channel activators Rho-kinase inhibitors Sulfonylureas Thiazolidinediones Vasopeptidase inhibitors Nitric oxide donors Capsaicin Amiloride |
| What is the newer metabolic modulator? | Ranolazine |
| What is the newer bradycardiac agent? | Ivabradine |
| What is the newer Potassium channel activators? | Nicorandil |
| What is the newer Rho-kinase inhibitor? | Fasudil |
| Newer sulfonylurea? | Glibenclamide |
| Newest Nitric oxide donor: | L- arginine |
| Additional Effects of CCBs: | A direct effect on HR and contractility (decrease) Indirect effect (from high doses) Increase HR and contractility (reflex) Enhance collateral vessel diameter The ratio of epicardial to endocardial blood flow/endo is increased |
| Nifedpine is not used in | cardiac arrhythmias , unlike verapmil which is effective in almost everything |