Exposure to calcium-free medium protects sensory fibers by capsaicin desensitization

Neurosci Lett. 1987 Sep 23;80(2):167-72. doi: 10.1016/0304-3940(87)90648-3.


Capsaicin (1 microM) produces a tetrodotoxin-resistant contraction of the rat isolated urinary bladder ascribable to neuropeptide release from sensory nerves. A second application of capsaicin (1-10 microM) up to 5 h from the first one was ineffective, indicating complete desensitization. However, if the first exposure to capsaicin was made after a prolonged incubation in a Ca-free medium containing EDTA (0.1 mM), a second application of capsaicin (1 microM) was still able to induce a contraction, thus indicating protection from desensitization.

MeSH terms

  • Animals
  • Calcium / metabolism*
  • Capsaicin / pharmacology*
  • In Vitro Techniques
  • Male
  • Muscle Contraction / drug effects*
  • Neurons, Afferent / drug effects
  • Neurons, Afferent / metabolism*
  • Neurons, Afferent / physiology
  • Rats
  • Rats, Inbred Strains
  • Urinary Bladder / drug effects
  • Urinary Bladder / innervation*
  • Urinary Bladder / physiology


  • Capsaicin
  • Calcium