Abstract
Distention of the proximal colon may have inhibitory or excitatory effects on the rectum and vice versa. The reflexes between the proximal colon and the rectum have not been well studied due to difficulties in accessing the proximal colon. The aim of this study was to investigate the reflex responses and their mechanisms between the proximal colon and the rectum in consideration of distention-related changes in tone and compliance of these regions as well as anal sphincter relaxation in a canine model. Proximal colon/rectal tone, compliance, and anal sphincter relaxation were investigated in six dogs chronically implanted with a proximal colon cannula while in the fasting state and during proximal colon distention or rectal distention. It was found that: 1) both rectal distention and proximal colon distention significantly and substantially decreased the compliance of the opposite regions, and guanethidine abolished proximal colon distention-induced changes in rectal compliance; 2) rectal/proximal colon distension decreased proximal colonic/rectal tone, and guanethidine abolished both of these inhibitory effects; 3) the anal sphincter was more sensitive to rectal distention than proximal colon distention; and 4) the minimal distention pressure required to induce anal inhibitory reflex was lower for rectal distention than proximal colon distention. It was concluded that distention-related changes in tone and compliance suggest the long inhibitory reflexes between the proximal colon and the rectum with the sympathetic involvement in rectal responses. The anal sphincter is more sensitive to the distention of the rectum than that of the proximal colon.
| Original language | English (US) |
|---|---|
| Journal | American Journal of Physiology - Regulatory Integrative and Comparative Physiology |
| Volume | 299 |
| Issue number | 3 |
| DOIs | |
| State | Published - Sep 1 2010 |
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Keywords
- Gastrointestinal motility
- Gastrointestinal reflex
- Sympathetic pathway
ASJC Scopus subject areas
- Physiology
- Physiology (medical)
Cite this
Colorectal and rectocolonic reflexes in canines : Involvement of tone, compliance, and anal sphincter relaxation. / Chen, Ji Hong; Sallam, Hanaa; Lin, Lin; Chen, Jiande D.Z.
In: American Journal of Physiology - Regulatory Integrative and Comparative Physiology, Vol. 299, No. 3, 01.09.2010.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Colorectal and rectocolonic reflexes in canines
T2 - Involvement of tone, compliance, and anal sphincter relaxation
AU - Chen, Ji Hong
AU - Sallam, Hanaa
AU - Lin, Lin
AU - Chen, Jiande D.Z.
PY - 2010/9/1
Y1 - 2010/9/1
N2 - Distention of the proximal colon may have inhibitory or excitatory effects on the rectum and vice versa. The reflexes between the proximal colon and the rectum have not been well studied due to difficulties in accessing the proximal colon. The aim of this study was to investigate the reflex responses and their mechanisms between the proximal colon and the rectum in consideration of distention-related changes in tone and compliance of these regions as well as anal sphincter relaxation in a canine model. Proximal colon/rectal tone, compliance, and anal sphincter relaxation were investigated in six dogs chronically implanted with a proximal colon cannula while in the fasting state and during proximal colon distention or rectal distention. It was found that: 1) both rectal distention and proximal colon distention significantly and substantially decreased the compliance of the opposite regions, and guanethidine abolished proximal colon distention-induced changes in rectal compliance; 2) rectal/proximal colon distension decreased proximal colonic/rectal tone, and guanethidine abolished both of these inhibitory effects; 3) the anal sphincter was more sensitive to rectal distention than proximal colon distention; and 4) the minimal distention pressure required to induce anal inhibitory reflex was lower for rectal distention than proximal colon distention. It was concluded that distention-related changes in tone and compliance suggest the long inhibitory reflexes between the proximal colon and the rectum with the sympathetic involvement in rectal responses. The anal sphincter is more sensitive to the distention of the rectum than that of the proximal colon.
AB - Distention of the proximal colon may have inhibitory or excitatory effects on the rectum and vice versa. The reflexes between the proximal colon and the rectum have not been well studied due to difficulties in accessing the proximal colon. The aim of this study was to investigate the reflex responses and their mechanisms between the proximal colon and the rectum in consideration of distention-related changes in tone and compliance of these regions as well as anal sphincter relaxation in a canine model. Proximal colon/rectal tone, compliance, and anal sphincter relaxation were investigated in six dogs chronically implanted with a proximal colon cannula while in the fasting state and during proximal colon distention or rectal distention. It was found that: 1) both rectal distention and proximal colon distention significantly and substantially decreased the compliance of the opposite regions, and guanethidine abolished proximal colon distention-induced changes in rectal compliance; 2) rectal/proximal colon distension decreased proximal colonic/rectal tone, and guanethidine abolished both of these inhibitory effects; 3) the anal sphincter was more sensitive to rectal distention than proximal colon distention; and 4) the minimal distention pressure required to induce anal inhibitory reflex was lower for rectal distention than proximal colon distention. It was concluded that distention-related changes in tone and compliance suggest the long inhibitory reflexes between the proximal colon and the rectum with the sympathetic involvement in rectal responses. The anal sphincter is more sensitive to the distention of the rectum than that of the proximal colon.
KW - Gastrointestinal motility
KW - Gastrointestinal reflex
KW - Sympathetic pathway
UR - http://www.scopus.com/inward/record.url?scp=77956705403&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=77956705403&partnerID=8YFLogxK
U2 - 10.1152/ajpregu.00439.2009
DO - 10.1152/ajpregu.00439.2009
M3 - Article
C2 - 20554930
AN - SCOPUS:77956705403
VL - 299
JO - American Journal of Physiology - Endocrinology and Metabolism
JF - American Journal of Physiology - Endocrinology and Metabolism
SN - 0193-1849
IS - 3
ER -