Fig. 1.
Schematic of the flexor digitorum brevis (FDB) muscle–nerve preparation. The isolated FDB muscle and tibial nerve were placed in the organ bath chamber, which was continuously perfused with oxygenated synthetic interstitial fluid solution. The distal part of tibial nerve was drawn through a small hole to the recording chamber, which was filled with mineral oil. After repeated dissection, single-fiber activity was recorded. When afferent responses to chemical application were tested, a smaller chamber was used to isolate the muscle. The synthetic interstitial fluid solution inside the small chamber was replaced with test solutions.