Fig. 3.

Representative single-fiber recordings illustrating acute sensitization by an inflammatory soup (IS) applied directly to the receptive ending of a stretch-sensitive muscular/muscular afferent (top) and persistent sensitization of a muscular-mucosal afferent ending 24 days after intracolonic zymosan instillation (bottom), a time at which colorectal hypersensitivity to distension was present, relative to the response of another muscular-mucosal afferent ending 24 days after intracolonic saline instillation (not hypersensitive). Note (top) that in addition to an increase in the response to stretch, response threshold was decreased from 91 mN to 31 mN after exposure to IS.