Acetylsalicylic acid action

Aspirin is the brand name of acetylsalicylic acid. It is the most widely used analgesic, antipyretic and antiinflammatory diug. Its main mode of action is iireversible acetylation of cyclooxygenases. 

Each Alka-Seltzer tablet contains 1916 mg of sodium bicarbonate, 1000 mg of citric acid (Fig. 9.1.2), and 325 mg of aspirin or acetylsalicylic acid (Fig. 9.1.3). Bromo Seltzer also contains sodium bicarbonate and citric acid as well as acetaminophen (Fig. 9.1.4). Several equilibria describe the action of bicarbonate-based antacid tablets. First of all, sodium bicarbonate dissolves completely in aqueous solution to generate sodium ions and bicarbonate ions ... 

Acetylsalicylic acid (ASA) exerts an antiinflammatory effect, in addition to its analgesic and antipyretic actions. 

Prostanoid mediators derived from arachidonic acid and sites of drug action. ASA, acetylsalicylic acid (aspirin) LT, leukotriene NSAID, nonsteroidal... 

Al-Humayyd, M.S. Effect of diltiazem, nifedipine and verapamil on the antinociceptive action of acetylsalicylic acid in mice, Gen. Pharmac.1991, 22, 121-125. 

Henrotin Y, Bassleer C, Franchimont P. In vitro effects of etodolac and acetylsalicylic acid on human chondrocyte metabolism. Agents Actions. 1992 36 317-323. 

Pharmacology studies the effects of drugs and how they exert their effects. For example, penicillin cures certain bacterial infections and acetylsalicylic acid (ASA) can reduce inflammation. How do they accomplish these respective effects Through research we now know that penicillin can disrupt the synthesis of cell walls in susceptible bacterial strains by inhibiting a key enzyme, while ASA can inhibit the action of a human cell membrane enzyme known as cyclooxygenase, which is responsible for the synthesis of a number of inflammatory mediators. 

Ott I, Schmidt K, Kircher B, Schumacher P, Wiglenda T, Gust R (2005) Antitumor-active cobalt-alkyne complexes derived from acetylsalicylic acid studies on the mode of drug action. J Med Chem 48 622-629... 

Figure 2.1 Acetylsalicylic acid 1 (Aspirin , Bayer) is much more than a prodrug of salicylic acid. Its major contribution to biological activity comes from a unique mechanism of action the activated acetyl group is transferred to a serine hydroxyl group in the binding site of cyclooxygenase. Merbaphen 2 (Novasurol , Bayer) was the first example of an organomercurial diuretic some analogs with less severe side effects were the therapeutic standard from about 1920 to 1950.

The covalent, irreversible mode of action of acetylsalicylic acid is important in its use for inhibiting thrombocyte aggregation in patients with cardiovascular disease (more specifically, atherosclerosis). This is a practically very im-... 

However, the story was not over. About 80 years after the introduction of Aspirin as a pain reliever, it was established that acetylsalicylic acid prevents heart attacks and strokes and reduces the risk of death during a suspected heart attack. In 1982, John R. Vane was awarded the Nobel Prize for medicine for discovering the basic mechanism of the action of acetylsalicylic acid. 

Mode of action. Acetylsalicylic acid is unique among NSAIDs in that it also irreversibly inhibits COX by acylating the active site of the enzyme, so preventing the formation of products including thromboxane, prostacyclin and other prostaglandins, imtil more COX is synthesised. Acetylsalicylic acid is rapidly hydrolysed to salicylic acid in the plasma. Salicylic acid also has an anti-inflammatory action but additionally exerts important effects on respiration, intermediary metabolism and acid-base balance, and it is highly irritant to the stomach. 

Protopine was shown to exhibit an inhibitory action on blood platelet aggregation induced by collagen, arachidonic acid, and ADP in vitro. In addition, protopine demonstrated equal or superior inhibitory effects when compared with that of the standard drugs acetylsalicylic acid or dipyridamole [266]. 

The inhibitors of COX enzymes are called nonsteroidal antiinflammatory drugs (NSAIDs) that are prescribed to relieve pain and fever. They stop prostaglandin and thromboxane production. Acetylsalicylic acid (aspirin) was used for this for many years and it was eventually discovered to acetylate a serine residue involved in the dioxygenase action of cyclooxygenases. A second class of NSAIDs, typified by ibuprofen (commonly called Advil or Motrin), inhibits catalysis by attaching irreversibly to cyclooxygenases. Aspirin and ibuprofen inhibit all prostaglandin and thromboxane synthesis. 

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