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[Why does nitroglycerin tolerance appear?]

L Włodek1, M Sokołowska

  • 1Instytut Biochemii Lekarskiej Collegium Medicum Uniwersytetu Jagiellońskiego w Krakowie.

Postepy Higieny I Medycyny Doswiadczalnej
|January 25, 2002
PubMed

Insights

Organic nitrates like nitroglycerin effectively treat coronary artery disease but cause tolerance. This tolerance stems from altered vascular smooth muscle bioactivation or physiological responses to increased nitric oxide production.

Area of Science:

  • Pharmacology
  • Cardiovascular Medicine
  • Biochemistry

Context:

  • Organic nitrates, including nitroglycerin, are vital for managing acute coronary artery disease.
  • Hemodynamic tolerance significantly limits the long-term efficacy of these essential medications.
  • Understanding tolerance mechanisms is crucial for optimizing nitrate therapy.

Purpose:

  • To review and categorize the primary mechanisms underlying the development of hemodynamic tolerance to organic nitrates.
  • To differentiate between vascular bioactivation changes and physiological responses to nitric oxide.

Summary:

  • Tolerance to organic nitrates involves two main categories of mechanisms.
  • These include alterations in how vascular smooth muscle bioactivates nitrates.
  • They also encompass physiological adaptations in response to increased nitric oxide (NO) signaling.

Impact:

  • Provides a framework for understanding nitrate tolerance in clinical practice.
  • Highlights key pathways that may be targeted for future therapeutic interventions.
  • Aids researchers in focusing on specific mechanisms to overcome drug limitations.

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