Differential effect of nitric oxide synthase inhibition on sigmoid colon longitudinal and circular muscle responses to nicotine and nerve stimulation in vitro. BJS 2004; 91: 229-234.
Published: 24th December 2003
Authors: H. C. McKirdy, C. E. Richardson, J. T. Green, J. Rhodes, G. T. Williams, R. W. Marshall et al.
Nicotine has been shown to release nitric oxide from nerves in human sigmoid colon. This effect has been used to investigate the innervation and functional relationship of the longitudinal and circular muscle layers.
Strips of longitudinal and circular muscle were obtained from 19 patients with colorectal cancer. The strips from ten patients were subjected to electrical field stimulation (EFS) in vitro using stimulus parameters for selective stimulation of nerves. The effect of nicotine 1–10 μmol/l on EFS responses was then measured in the presence and absence of a nitric oxide synthase inhibitor, nitro‐
Both longitudinal and circular strips responded to EFS with contraction. The time to achieve a peak contractile response (time to peak; TTP) was significantly longer (P < 0·001) in circular strips.
These findings suggest that nitric oxide release on neural stimulation is greater in circular than in longitudinal muscle. Copyright © 2003 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.Full text