OBJECTIVE: To examine the effects of esophageal stimulation on vagal afferent and efferent pathways in volunteers without diabetes and patients with diabetes. DESIGN: Prospective physiological study. PARTICIPANTS: Fourteen control subjects without diabetes and 6 patients with diabetes. INTERVENTIONS: Electrical and mechanical stimulation of the esophagus. OUTCOME MEASURES: Cortical evoked potentials and the power spectra of heart rate variability. RESULTS: For the control subjects, there was a significant decrease in the ratio of the low frequency to high frequency (LF:HF) power (i.e., increased vagal efferent modulation) during stimulation. Reproducible cortical evoked potentials were obtained from all control subjects. In the 6 patients with diabetes, who had viscerosensory and autonomic neuropathy, the cortical evoked potentials showed an erratic non-reproducible response to electrical esophageal stimulation; however, the LF:HF ratio decreased in these patients during stimulation, suggesting an intact subcortical reflex circuit. CONCLUSIONS: Vago-afferent fibres can be studied using minimally invasive techniques, and the power spectral analysis of heart rate variability permits study of autonomic vago-efferent pathways.
OBJECTIVE: To examine the effects of esophageal stimulation on vagal afferent and efferent pathways in volunteers without diabetes and patients with diabetes. DESIGN: Prospective physiological study. PARTICIPANTS: Fourteen control subjects without diabetes and 6 patients with diabetes. INTERVENTIONS: Electrical and mechanical stimulation of the esophagus. OUTCOME MEASURES: Cortical evoked potentials and the power spectra of heart rate variability. RESULTS: For the control subjects, there was a significant decrease in the ratio of the low frequency to high frequency (LF:HF) power (i.e., increased vagal efferent modulation) during stimulation. Reproducible cortical evoked potentials were obtained from all control subjects. In the 6 patients with diabetes, who had viscerosensory and autonomic neuropathy, the cortical evoked potentials showed an erratic non-reproducible response to electrical esophageal stimulation; however, the LF:HF ratio decreased in these patients during stimulation, suggesting an intact subcortical reflex circuit. CONCLUSIONS: Vago-afferent fibres can be studied using minimally invasive techniques, and the power spectral analysis of heart rate variability permits study of autonomic vago-efferent pathways.
Authors: Chao Qin; Marie L M Ghorbani; Mingyuan Wu; Jay P Farber; Jianxing Ma; Robert D Foreman Journal: Auton Neurosci Date: 2008-11-22 Impact factor: 3.145
Authors: Christina Brock; Romulus E Lontis; Flemming H Lundager; Peter Kunwald; Asbjørn M Drewes; Hans Gregersen Journal: Gastroenterol Res Pract Date: 2011-11-15 Impact factor: 2.260