Colonic Tone and Motility in Patients With Irritable Bowel Syndrome
MARIO J. VASSALLO, M.D.,* MICHAEL CAMILLERI, M.D., SIDNEY F. PHILLIPS, M.D., CHARLES J. STEADMAN, M.B.,B.S.,t NICHOLAS J. TALLEY, M.B.,B.S., Ph.D., RUSSELL B. HANSON, B.S., ANNE C. HADDAD, B.S.,:j: Gastroenterology Research Unit
In this study, our aim was to test the hypothesis that colonic tone is abnormal in patients with irritable bowel syndrome (mS). We studied eight patients with ms and eight age-matched asymptomatic control subjects, in whom tone and motility were measured by an electronic barostat and by pneumohydrauJic perfusion manometry, respectively. Tone and motility were recorded from the descending colon for a 14-hour period-3 hours awake, 7 hours asleep, 2 hours fasting after awakening, and 2 hours postprandially. In patients with ms and in healthy subjects, colonic tone decreased by up to 50% during sleep and increased promptly on awakening. Fasting colonic tone (as quantified by the volume in the barostat balloon) in the awake state was not significantly higher in patients with ms than it was in healthy subjects (125 ± 13 versus 152 ± 15 ml; P =0.19). Tone increased postprandially in both study groups, and the increase was greater in healthy subjects than it was in patients with ms (P0.2), and the median volumes of the balloon during fasting were slightly but insignificantly less in the patients than in the healthy subjects (125 ± 13 versus 152 ± 15 ml; P = 0.19). The motility index during fasting (Fig. 4) was significantly greater in the patients with IBS than in the healthy subjects (3.2 ± 0.6 versus L6 ± 0.4; P = 0,05). Postprandial Colonic Tone and Motility.-Eating produced no significant change in motility index or tone in the patients with IBS (Fig, 4 and 5), In the healthy subjects, the increases in motility and tone during the first postprandial hour were significant (Fig. 4 and 5), High-Amplitude Prolonged Contractions.-The numbers of high-amplitude prolonged contractions per hour during the fasting study were 73 ± 3,7 in patients with IBS and LO ± 0.7 in healthy control subjects (P>0.1). During the postprandial hours, the corresponding numbers were
728
Mayo CUn Proc, August 1992, Vol 67
COLONIC TONE AND MOTILITY IN IRRITABLE BOWEL SYNDROME
171
110
In 100
.,.
71
10
U
= e
II< II II .:l
GIl
MINUTES Fig. 2. Bar graph of percentage changes in median volumes (±standard error) in the barostat balloon for a period of 10 hours in healthy subjects and patients with irritable bowel syndrome (IBS). Volumes were greatest during sleep, and they declined substantially on awakening.
I
c::J
•
IDALTB
~ 1B8
~
\iii Q
...z
t:
:3 ... ~
'Ii I
Q
:II 1
.
!
110
a
~
MINUTES Fig. 3. Bar graph of mean motility index (±standard error) every 30 minutes for a period of 10 hours. Data were derived from phasic pressure waves recorded 7 em caudad to the barostat balloon. In asymptomatic subjects and patients with irritable bowel syndrome (IBS), the lowest motility indices were measured during sleeping period. In contrast, the highest indices were recorded soon after awakening.
COLONIC TONE AND MOTILITY IN IRRITABLE BOWEL SYNDROME
Mayo Clio Proc, August 1992, Vol 67
1,--------
..,
729
171..,....-------------------, v. c:::::J
c:::::J IIL\LTB E:ZZl lB.
• peO.OI
r..tl..
150
4
UALTB
EZZl lB.
= ~ a
§
S
I
JI
Fln& P",,&pr. .dl.l
hour
o ............._~~.L__ ......._~~.L__......._"""'"''"'''''..........
s.co••
8eeo•• Po.t:pr....al boar
Flro& Poet:pr. .'lal boar
Poo&pr . .dlal boar
Fig. 4. Histogram showing significantly higher mean motility indexduringfasting in patients withirritable bowelsyndrome (IRS) than in healthy subjects. During first postprandial hour, the mean motility index increased significantly in healthy subjects but not in patients with IBS.
Fig. 5. Histogram comparing change in barostatballoon volumes fromfastingto postprandial periodsin healthy subjects and patients with irritable bowel syndrome (IRS). Note significant increasein tone in healthysubjects but not in patientswith IBS.
7.1 ± 3.9 and 3.6 ± 2.3, respectively; these differences also were not statistically significant because of wide variations between individuals (P = 0.1). Moreover, the study populations apparently lacked homogeneity (Table 1). One subject in the control group (case 7) and three with IBS (cases 2, 5, and 7) contributed predominantly to the prevalence of highamplitude prolonged contractions.
We had predicted that the basal, fasting colonic tone would be increased in patients with IBS; thus, we were surprised that it was not significantly different from that of control subjects. In contrast, tone increased significantly in response to eating in healthy subjects but not in patients with IBS (Fig. 5); indeed, the tone achieved in response to ingestion of food was similar in both groups. Perhaps the failure of the colon in patients with IBS to have significantly increased tone postprandially indicates that the tone during fasting was indeed increased. In this regard, problems inherent in the classification of patients with IBS 4.8.9 and the
DISCUSSION Colonic manometry has been examined extensively for 50 years in patients with IBS, and most observers have found excessive phasic pressures in the rectosigmoid region in response to mental stress, drugs, balloon distention, and eating and in those patients thought to have prominent "gastrocolonic reflexes."7.15.16 Results of manometric studies during fasting, however, have often been similar in patients with IBS and control subjects.":" Another feature that somewhat consistently distinguishes IBS from health is the response to balloon distention of the colon.7.15.19 The small bowel' and colon" of patients with IBS are both hypersensitive to stretch; indeed, some reports suggest that these responses even differ among subgroups of IBS.8 These observations raised the possibility that the tone of the bowel wall in IBS may differ from normal. Thus, because conventional manometry has detected no consistent pathophysiologic features of IBS, the current study was designed to monitor colonic tone continuously with use of an electronic barostat.
Table I.-Number of Colonic High-Amplitude Prolonged Contractions in Healthy Control Subjects and Patients With ms*
Subject 1 2 3 4 5 6 7 8
Controlsubjects (pressure peaks/h) Fasting period Postprandial 0 4 0 0 0 0 0 4
4 1 0 0 0 2 19 3
*IBS = irritablebowel syndrome.
Patientswith IBS (pressure peaks/h) Fasting period Postprandial 0 15 2 4 7 0 30 0
5 1 1 4 33 0 12 1
730
COLONIC TONE AND MOTILITY IN IRRITABLE BOWEL SYNDROME
relatively small number of subjects we studied may have led to our failing to detect a significant difference in basal tone. The other physiologic variable we tested-the effect of overnight sleep-also did not distinguish between healthy subjects and patients with IBS. Colonic tone relaxed normally during nocturnal sleep in patients with IBS. This finding is consistent with reports that dysmotility of the small bowel in patients with IBS disappears during nocturnal sleep." Motility indices did not show the same clear-cut response to overnight sleep; values varied substantially, but no obvious difference was noted among subject groups. On the next morning, manometric indices for the fasting state were greater in patients with IBS than in control subjects. This finding was not in accord with earlier studies of the upper rectum and rectosigmoid region? that failed to show basal differences between patients with IBS and control subjects, but it was consistent with other studies of the descending colon." Our finding that eating significantly augmented motility indices in healthy subjects but not in patients with IBS differed from the findings reported by Rogers and associates," however. The causative mechanism for diarrhea in IBS is unknown. Considerable variability among subjects precluded our detection of group differences for the number of high-amplitude prolonged contractions, although the hypothesis that these propulsive waves are the pathophysiologic mechanism in diarrheal disease is attractive." We noted a clear trend of more frequent contractions in patients with IBS than in healthy subjects, although substantial individual variability existed (Table I). Selection of patients continues to complicate all research on IBS-not only may the symptomatic subjects constitute a heterogeneous group but also the group of asymptomatic "control subjects" may include "nonpatients" with IBSY Pressure in the barostat bag was approximately 11 mm Hg, and volumes varied from approximately 100 to 150 ml. Despite this level of distention, our patients and healthy volunteers experienced no pain or discomfort. These findings contrast with those of Ritchie," who noted "colonic hyperalgesia" with use of a 3.4- to 3.8-cm diameter balloon in the rectum, and with the sensation of rectal discomfort noted at mean volumes of 80- to 140-rnl distention in a recent study by Prior and colleagues." The lack of perception of any abnormal sensation induced by the barostat balloon in our patients suggests that our measurements of colonic tone and motility were probably unaffected by distending pressures in the balloon. ACKNOWLEDGMENT We thank the director and staff of the Clinical Research Center, Saint Marys Hospital, for care of the study patients and Lois A. Law for preparing the submitted manuscript.
Mayo Clin Proc, August 1992, Vol 67
REFERENCES 1. Manning AP, Thompson WG, Heaton KW, Morris AF: Towards positive diagnosis of the irritable bowel. Br Med J 2:653-654, 1978 2. Talley NJ, Phillips SF, Melton U, Mulvihill C, Wiltgen C, Zinsmeister AR: Diagnostic value of the Manning criteria in irritable bowel syndrome. Gut 31:77-81, 1990 3. Thompson WG, Dotevall G, Drossman DA, Heaton KW, Kruis W: Irritable bowel syndrome: guidelines for the diagnosis. Gastroenterollnt 2:92-95, 1989 4. Drossman DA, Thompson WG, Talley NJ, Funch-Jensen P, Janssens J, Whitehead WE: Identification of sub-groups of functional gastrointestinal disorders. Gastroenterol Int 3:159-172, 1990 5. Kellow IE, Phillips SF: Altered small bowel motility in irritable bowel syndrome is correlated with symptoms. Gastroenterology 92:1885-1893,1987 6. Kellow JE, Gill RC, Wingate DL: Prolonged ambulant recordings of small bowel motility demonstrate abnormalities in the irritable bowel syndrome. Gastroenterology 98:12081218, 1990 7. Snape WJ Jr: Irritable colon syndrome. In Pathogenesis of Functional Bowel Disease. Edited by WJ Snape Jr. New York, Plenum Medical Book Company, 1989, pp 227-248 8. Whitehead WE, Engel BT, Schuster MM: Irritable bowel syndrome: physiological and psychological differences between diarrhea-predominant and constipation-predominant patients. Dig Dis Sci 25:404-413, 1980 9. Prior A, Maxton DG, Whorwell PJ: Anorectal manometry in irritable bowel syndrome: differences between diarrhoea and constipation predominant subjects. Gut 31:458-462, 1990 10. Vassallo M, Camilleri M, Phillips SF, Brown ML, Chapman NJ, Thomforde GM: Transit through the proximal colon influences stool weight in the irritable bowel syndrome. Gastroenterology 102:102-108, 1992 11. Kamath PS, Phillips SF, O'Connor MK, Brown ML, Zinsmeister AR: Colonic capacitance and transit in man: modulation by luminal contents and drugs. Gut 31:443-449, 1990 12. Steadman CJ, Phillips SF, Camilleri M, Haddad AC, Hanson RB: Variation of muscle tone in the human colon. Gastroenterology 101:373-381, 1991 13. Steadman CJ, Phillips SF, Camilleri M, Talley NJ, Haddad A, Hanson R: Control of muscle tone in the human colon. Gut 33:541-546,1992 14. Narducci F, Bassetti G, Gaburri M, Morelli A: Twenty four hour manometric recording of colonic motor activity in healthy man, Gut 28:17-25,1987 15. Ritchie J: Pain from distension of the pelvic colon by inflating a balloon in the irritable bowel syndrome. Gut 14:125132, 1973 16. Chaudhary NA, Truelove SC: Human colonic motility: a comparative study of normal subjects, patients with ulcerative colitis, and patients with the irritable colon syndrome. I. Resting patterns of motility. Gastroenterology 40:1-17, 1961 17. Connell AM, Jones FA, Rowlands EN: Motility of the pelvic colon. Part IV. Abdominal pain associated with colonic hypermotility after meals. Gut 6:105-112,1965 18. Sullivan MA, Cohen S, Snape WJ Jr: Colonic myoelectrical activity in irritable-bowel syndrome: effect of eat-
Mayo CUn Proc, August1992, Vol 67
19. 20.
21.
COLONIC TONEANDMOTILITY IN IRRITABLE BOWEL SYNDROME
ing and anticholinergics. N Engl J Med 298:878-883, 1978 Kingham JGC, Dawson AM: Origin of chronic right upper quadrant pain. Gut 26:783-788, 1985 Kumar D, Soffer EE, Wingate DL, Britto J, Das-Gupta A, Mridha K: Modulation of the duration of human postprandial motor activity by sleep. Am J Physiol 256:G851-G855, 1989 Rogers J, Henry MM, Misiewicz II: Increased segmental activity and intraluminal pressures in the sigmoid colon of
22.
23.
731
patients with the irritable bowel syndrome. Gut 30:634-641, 1989 Bazzocchi G, Ellis J, Villanueva-Meyer J, Jing J, Reddy SN, Mena I, Snape WJ Jr: Postprandial colonic transit and motor activity in chronic constipation. Gastroenterology 98:686693, 1990 Thompson WG, Heaton KW: Functional bowel disorders in apparently healthy people. Gastroenterology 79:283-288, 1980
MARIO J. VASSALLO, M.D.,* MICHAEL CAMILLERI, M.D., SIDNEY F. PHILLIPS, M.D., CHARLES J. STEADMAN, M.B.,B.S.,t NICHOLAS J. TALLEY, M.B.,B.S., Ph.D., RUSSELL B. HANSON, B.S., ANNE C. HADDAD, B.S.,:j: Gastroenterology Research Unit
In this study, our aim was to test the hypothesis that colonic tone is abnormal in patients with irritable bowel syndrome (mS). We studied eight patients with ms and eight age-matched asymptomatic control subjects, in whom tone and motility were measured by an electronic barostat and by pneumohydrauJic perfusion manometry, respectively. Tone and motility were recorded from the descending colon for a 14-hour period-3 hours awake, 7 hours asleep, 2 hours fasting after awakening, and 2 hours postprandially. In patients with ms and in healthy subjects, colonic tone decreased by up to 50% during sleep and increased promptly on awakening. Fasting colonic tone (as quantified by the volume in the barostat balloon) in the awake state was not significantly higher in patients with ms than it was in healthy subjects (125 ± 13 versus 152 ± 15 ml; P =0.19). Tone increased postprandially in both study groups, and the increase was greater in healthy subjects than it was in patients with ms (P0.2), and the median volumes of the balloon during fasting were slightly but insignificantly less in the patients than in the healthy subjects (125 ± 13 versus 152 ± 15 ml; P = 0.19). The motility index during fasting (Fig. 4) was significantly greater in the patients with IBS than in the healthy subjects (3.2 ± 0.6 versus L6 ± 0.4; P = 0,05). Postprandial Colonic Tone and Motility.-Eating produced no significant change in motility index or tone in the patients with IBS (Fig, 4 and 5), In the healthy subjects, the increases in motility and tone during the first postprandial hour were significant (Fig. 4 and 5), High-Amplitude Prolonged Contractions.-The numbers of high-amplitude prolonged contractions per hour during the fasting study were 73 ± 3,7 in patients with IBS and LO ± 0.7 in healthy control subjects (P>0.1). During the postprandial hours, the corresponding numbers were
728
Mayo CUn Proc, August 1992, Vol 67
COLONIC TONE AND MOTILITY IN IRRITABLE BOWEL SYNDROME
171
110
In 100
.,.
71
10
U
= e
II< II II .:l
GIl
MINUTES Fig. 2. Bar graph of percentage changes in median volumes (±standard error) in the barostat balloon for a period of 10 hours in healthy subjects and patients with irritable bowel syndrome (IBS). Volumes were greatest during sleep, and they declined substantially on awakening.
I
c::J
•
IDALTB
~ 1B8
~
\iii Q
...z
t:
:3 ... ~
'Ii I
Q
:II 1
.
!
110
a
~
MINUTES Fig. 3. Bar graph of mean motility index (±standard error) every 30 minutes for a period of 10 hours. Data were derived from phasic pressure waves recorded 7 em caudad to the barostat balloon. In asymptomatic subjects and patients with irritable bowel syndrome (IBS), the lowest motility indices were measured during sleeping period. In contrast, the highest indices were recorded soon after awakening.
COLONIC TONE AND MOTILITY IN IRRITABLE BOWEL SYNDROME
Mayo Clio Proc, August 1992, Vol 67
1,--------
..,
729
171..,....-------------------, v. c:::::J
c:::::J IIL\LTB E:ZZl lB.
• peO.OI
r..tl..
150
4
UALTB
EZZl lB.
= ~ a
§
S
I
JI
Fln& P",,&pr. .dl.l
hour
o ............._~~.L__ ......._~~.L__......._"""'"''"'''''..........
s.co••
8eeo•• Po.t:pr....al boar
Flro& Poet:pr. .'lal boar
Poo&pr . .dlal boar
Fig. 4. Histogram showing significantly higher mean motility indexduringfasting in patients withirritable bowelsyndrome (IRS) than in healthy subjects. During first postprandial hour, the mean motility index increased significantly in healthy subjects but not in patients with IBS.
Fig. 5. Histogram comparing change in barostatballoon volumes fromfastingto postprandial periodsin healthy subjects and patients with irritable bowel syndrome (IRS). Note significant increasein tone in healthysubjects but not in patientswith IBS.
7.1 ± 3.9 and 3.6 ± 2.3, respectively; these differences also were not statistically significant because of wide variations between individuals (P = 0.1). Moreover, the study populations apparently lacked homogeneity (Table 1). One subject in the control group (case 7) and three with IBS (cases 2, 5, and 7) contributed predominantly to the prevalence of highamplitude prolonged contractions.
We had predicted that the basal, fasting colonic tone would be increased in patients with IBS; thus, we were surprised that it was not significantly different from that of control subjects. In contrast, tone increased significantly in response to eating in healthy subjects but not in patients with IBS (Fig. 5); indeed, the tone achieved in response to ingestion of food was similar in both groups. Perhaps the failure of the colon in patients with IBS to have significantly increased tone postprandially indicates that the tone during fasting was indeed increased. In this regard, problems inherent in the classification of patients with IBS 4.8.9 and the
DISCUSSION Colonic manometry has been examined extensively for 50 years in patients with IBS, and most observers have found excessive phasic pressures in the rectosigmoid region in response to mental stress, drugs, balloon distention, and eating and in those patients thought to have prominent "gastrocolonic reflexes."7.15.16 Results of manometric studies during fasting, however, have often been similar in patients with IBS and control subjects.":" Another feature that somewhat consistently distinguishes IBS from health is the response to balloon distention of the colon.7.15.19 The small bowel' and colon" of patients with IBS are both hypersensitive to stretch; indeed, some reports suggest that these responses even differ among subgroups of IBS.8 These observations raised the possibility that the tone of the bowel wall in IBS may differ from normal. Thus, because conventional manometry has detected no consistent pathophysiologic features of IBS, the current study was designed to monitor colonic tone continuously with use of an electronic barostat.
Table I.-Number of Colonic High-Amplitude Prolonged Contractions in Healthy Control Subjects and Patients With ms*
Subject 1 2 3 4 5 6 7 8
Controlsubjects (pressure peaks/h) Fasting period Postprandial 0 4 0 0 0 0 0 4
4 1 0 0 0 2 19 3
*IBS = irritablebowel syndrome.
Patientswith IBS (pressure peaks/h) Fasting period Postprandial 0 15 2 4 7 0 30 0
5 1 1 4 33 0 12 1
730
COLONIC TONE AND MOTILITY IN IRRITABLE BOWEL SYNDROME
relatively small number of subjects we studied may have led to our failing to detect a significant difference in basal tone. The other physiologic variable we tested-the effect of overnight sleep-also did not distinguish between healthy subjects and patients with IBS. Colonic tone relaxed normally during nocturnal sleep in patients with IBS. This finding is consistent with reports that dysmotility of the small bowel in patients with IBS disappears during nocturnal sleep." Motility indices did not show the same clear-cut response to overnight sleep; values varied substantially, but no obvious difference was noted among subject groups. On the next morning, manometric indices for the fasting state were greater in patients with IBS than in control subjects. This finding was not in accord with earlier studies of the upper rectum and rectosigmoid region? that failed to show basal differences between patients with IBS and control subjects, but it was consistent with other studies of the descending colon." Our finding that eating significantly augmented motility indices in healthy subjects but not in patients with IBS differed from the findings reported by Rogers and associates," however. The causative mechanism for diarrhea in IBS is unknown. Considerable variability among subjects precluded our detection of group differences for the number of high-amplitude prolonged contractions, although the hypothesis that these propulsive waves are the pathophysiologic mechanism in diarrheal disease is attractive." We noted a clear trend of more frequent contractions in patients with IBS than in healthy subjects, although substantial individual variability existed (Table I). Selection of patients continues to complicate all research on IBS-not only may the symptomatic subjects constitute a heterogeneous group but also the group of asymptomatic "control subjects" may include "nonpatients" with IBSY Pressure in the barostat bag was approximately 11 mm Hg, and volumes varied from approximately 100 to 150 ml. Despite this level of distention, our patients and healthy volunteers experienced no pain or discomfort. These findings contrast with those of Ritchie," who noted "colonic hyperalgesia" with use of a 3.4- to 3.8-cm diameter balloon in the rectum, and with the sensation of rectal discomfort noted at mean volumes of 80- to 140-rnl distention in a recent study by Prior and colleagues." The lack of perception of any abnormal sensation induced by the barostat balloon in our patients suggests that our measurements of colonic tone and motility were probably unaffected by distending pressures in the balloon. ACKNOWLEDGMENT We thank the director and staff of the Clinical Research Center, Saint Marys Hospital, for care of the study patients and Lois A. Law for preparing the submitted manuscript.
Mayo Clin Proc, August 1992, Vol 67
REFERENCES 1. Manning AP, Thompson WG, Heaton KW, Morris AF: Towards positive diagnosis of the irritable bowel. Br Med J 2:653-654, 1978 2. Talley NJ, Phillips SF, Melton U, Mulvihill C, Wiltgen C, Zinsmeister AR: Diagnostic value of the Manning criteria in irritable bowel syndrome. Gut 31:77-81, 1990 3. Thompson WG, Dotevall G, Drossman DA, Heaton KW, Kruis W: Irritable bowel syndrome: guidelines for the diagnosis. Gastroenterollnt 2:92-95, 1989 4. Drossman DA, Thompson WG, Talley NJ, Funch-Jensen P, Janssens J, Whitehead WE: Identification of sub-groups of functional gastrointestinal disorders. Gastroenterol Int 3:159-172, 1990 5. Kellow IE, Phillips SF: Altered small bowel motility in irritable bowel syndrome is correlated with symptoms. Gastroenterology 92:1885-1893,1987 6. Kellow JE, Gill RC, Wingate DL: Prolonged ambulant recordings of small bowel motility demonstrate abnormalities in the irritable bowel syndrome. Gastroenterology 98:12081218, 1990 7. Snape WJ Jr: Irritable colon syndrome. In Pathogenesis of Functional Bowel Disease. Edited by WJ Snape Jr. New York, Plenum Medical Book Company, 1989, pp 227-248 8. Whitehead WE, Engel BT, Schuster MM: Irritable bowel syndrome: physiological and psychological differences between diarrhea-predominant and constipation-predominant patients. Dig Dis Sci 25:404-413, 1980 9. Prior A, Maxton DG, Whorwell PJ: Anorectal manometry in irritable bowel syndrome: differences between diarrhoea and constipation predominant subjects. Gut 31:458-462, 1990 10. Vassallo M, Camilleri M, Phillips SF, Brown ML, Chapman NJ, Thomforde GM: Transit through the proximal colon influences stool weight in the irritable bowel syndrome. Gastroenterology 102:102-108, 1992 11. Kamath PS, Phillips SF, O'Connor MK, Brown ML, Zinsmeister AR: Colonic capacitance and transit in man: modulation by luminal contents and drugs. Gut 31:443-449, 1990 12. Steadman CJ, Phillips SF, Camilleri M, Haddad AC, Hanson RB: Variation of muscle tone in the human colon. Gastroenterology 101:373-381, 1991 13. Steadman CJ, Phillips SF, Camilleri M, Talley NJ, Haddad A, Hanson R: Control of muscle tone in the human colon. Gut 33:541-546,1992 14. Narducci F, Bassetti G, Gaburri M, Morelli A: Twenty four hour manometric recording of colonic motor activity in healthy man, Gut 28:17-25,1987 15. Ritchie J: Pain from distension of the pelvic colon by inflating a balloon in the irritable bowel syndrome. Gut 14:125132, 1973 16. Chaudhary NA, Truelove SC: Human colonic motility: a comparative study of normal subjects, patients with ulcerative colitis, and patients with the irritable colon syndrome. I. Resting patterns of motility. Gastroenterology 40:1-17, 1961 17. Connell AM, Jones FA, Rowlands EN: Motility of the pelvic colon. Part IV. Abdominal pain associated with colonic hypermotility after meals. Gut 6:105-112,1965 18. Sullivan MA, Cohen S, Snape WJ Jr: Colonic myoelectrical activity in irritable-bowel syndrome: effect of eat-
Mayo CUn Proc, August1992, Vol 67
19. 20.
21.
COLONIC TONEANDMOTILITY IN IRRITABLE BOWEL SYNDROME
ing and anticholinergics. N Engl J Med 298:878-883, 1978 Kingham JGC, Dawson AM: Origin of chronic right upper quadrant pain. Gut 26:783-788, 1985 Kumar D, Soffer EE, Wingate DL, Britto J, Das-Gupta A, Mridha K: Modulation of the duration of human postprandial motor activity by sleep. Am J Physiol 256:G851-G855, 1989 Rogers J, Henry MM, Misiewicz II: Increased segmental activity and intraluminal pressures in the sigmoid colon of
22.
23.
731
patients with the irritable bowel syndrome. Gut 30:634-641, 1989 Bazzocchi G, Ellis J, Villanueva-Meyer J, Jing J, Reddy SN, Mena I, Snape WJ Jr: Postprandial colonic transit and motor activity in chronic constipation. Gastroenterology 98:686693, 1990 Thompson WG, Heaton KW: Functional bowel disorders in apparently healthy people. Gastroenterology 79:283-288, 1980
