Dorsal root ganglion stimulation to modulate mechanosensitive colorectal afferent transmission

Study Purpose: The objective of this study is to determine the parameters of electrical stimulation of the dorsal root ganglia (L6 in mice) that reversibly blocks visceral afferent neural transmission.

Data Collection: The dataset consists of functional responses of colorectal afferents to mechanical stimuli applied to the attached colorectum in an ex vivo preparation with colorectum, pelvic nerve, DRG and dorsal root in continuity. Electrical stimulation was delivered to the DRG to assess the blocking effect of colorectal afferent neural transmission.

Primary Conclusion: Sub-kilohertz DRG stimulation significantly attenuates colorectal afferent transmission (10, 50, 100, 500 and 1000 Hz), of which 50 and 100 Hz show superior blocking effects.

Curator's Notes

Experimental Design: The L6 dorsal root ganglion (DRG) with an attached dorsal root (DR) and a segment of the spinal nerve (SN) was carefully harvested in continuity and transferred to a custom-built recording chamber consisting of a tissue chamber and an adjacent recording chamber. The L6 DRG was placed in the tissue chamber perfused with oxygenated Krebs solution at 30°C, and the DR was gently pulled into the recording chamber filled with mineral oil to enhance the signal-to-noise ratio of the recording. The L6 DR was carefully split into fine filaments (∼10 μm) to achieve single-fiber recordings from individual afferent. A DRG stimulation protocol consisted of 30 pulse trains at 0.5 Hz train frequency and 0.5-second intertrain intervals (60 seconds in total). Pulse frequencies for DRG stimulation were set to be one of the following: 10, 50, 100, 500, or 1000 Hz. Action potentials evoked by CRD stimulation was recorded from split DR filaments and processed off-line to identify individual action potentials and compute CV using customized MATLAB programs. The experiments were conducted with tissues harvested from mice receiving intracolonic treatment of 2,4,6-trinitrobenzenesulfonic acid (TNBS), a model of postinfectious Irritable bowel syndrome (IBS), and untreated (Naive) mice.

Completeness: This dataset is part of a larger study:"Topology and molecular profiles of nociceptive DRG neurons innervating distal colon and rectum"

Subjects & Samples: Male (n=9) and female (n=5) mice (RRID:IMSR_TAC:b6) 8-13 weeks old were used in this study.

Primary vs derivative data: Primary data is organized in folders by the subject ID and contains Matlab files with a single-fiber action potential recordings(.mat). There is no derivative data folder.