In spite of its effective analgesic activity aspirin is used in prevention of formation of atherosclerotic disorder – explain why??

Aspirin, also known as acetylsalicylic acid (ASA), is a nonsteroidal anti-inflammatory drug (NSAID) used to reduce pain, fever, and/or inflammation, and as an antithrombotic.  

Aspirin is widely known for its analgesic (pain-relieving) properties, but it also plays a crucial role in the prevention of atherosclerotic disorders.

Aspirin irreversibly inactivates the Cyclooxygenase Enzyme (Prostaglandin Endoperoxide Synthase) in the Arachidonic Acid Metabolism Pathway, and supress the production of Prostaglandin (PGs) and Thromboxane (TXs) and Prostacyclin (Prostanoids). 

Atherosclerosis, also known as arteriosclerosis, is a condition where the arteries become thick and stiff due to the buildup of plaque. The plaque can also burst, leading to a blood clot. 

  • ASPIRIN EFFECT ON PLATELETs (TXA2 mechanism): 
  1. Aspirin irreversibly blocks both COX-1 & COX-II enzyme thereby inhibiting the conversion of Arachidonic Acid to PGG2 and PGH2 
  2. So, further conversion of PGH2 to different PGs and Thromboxanes and Prostacycline is restricted. 
  3. COX-1 is majorly expressed in Mature platelets, so inhibition of this enzyme blocks the conversion of AA to TXA2,
  4. We know, TXA2 upon binding with TP receptor in mature platelets promotes platelet aggregation, so inhibition of this enzyme thereby inhibits the platelet aggregation which is a great pathological factor in the aggression of Atherosclerosis. 
  • ASPIRIN EFFECT ON KIDNEY:
  1. We know, TXA2 is a potent vasoconstrictor in Renal Blood flow. 
  2. So, TXA2 decreases the glomerular filtration rate.
  3. Decreased Glomerular Filtration results in increase in blood pressure.
  4. Increased BP is responsible for different CVS complexations. If BP is increased too much there is a chance for the blood vessel rapture, which is a major cause of Atherosclerosis. 
  5. Aspirin Blocks the TXA2 production in kidney as a result BP becomes low, and chances for rapture of blood vessel become Less. 



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