Interactions of inflammatory mediators and low pH not influenced by capsazepine in rat cutaneous nociceptors.

The rat skin-saphenous nerve preparation was used to record from mechano-heat sensitive C-fibers whose receptive fields were superfused with various solutions of low pH and of bradykinin, serotonin and prostaglandin E 2 . Only synchronous application of protons and mediators resulted in a significant nearly three-fold augmentation of the nociceptive pH response, and capsazepine (10 -5 M) did not block this short-lived enhancement. Thus, it does not seem to involve the capsaicin receptor (VRI) which is in contrast to a previous finding from cultured sensory neurons.