Octreotide reduces perception of rectal electrical stimulation by spinal afferent pathway inhibition. Chey, William D., Ahmad Beydoun, David J. Roberts, William L. Hasler, Chung Owyang. Deptartment of Internal Medicine and Department of Neurology, University of Michigan Medical Center, Ann Arbor, MI
APStracts 2:0117G, 1995.
Octreotide reduces perception of rectal distention in normal volunteers and irritable bowel patients. To localize octreotide's site of action, perceptual and evoked potential (EP) responses to rectal electrical stimulation were tested in 7 normal volunteers after double-blind octreotide (100 [mu]g sq) or placebo. After octreotide, the currents needed to elicit threshold perception of square wave impulses delivered to the rectum were 29% higher than after placebo. When electrical stimulation was delivered at constant currents 50% above threshold, rectal perception scores were significantly reduced after octreotide compared to placebo. Rectal electrical stimulation led to characteristic and reproducible cerebral evoked potentials. Octreotide had no effect on latencies, but reduced peak to peak amplitudes by 35% compared to placebo. Rectal electrical stimulation also led to characteristic and reproducible spinal evoked potentials. Octreotide had no effect on spinal latencies, but reduced peak to peak amplitudes by 51%. In conclusion, octreotide reduces perception of rectal electrical stimulation, which is associated with inhibition of cerebral and spinal evoked potential amplitude indicating effects on spinal afferent pathways.

Received 4 March 1994; accepted in final form 26 May 1995.
APS Manuscript Number G88-4.
Article publication pending Am. J. Physiol. (Gastrointest. Liver
Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on  6 July 1995.