Patterns of electrical activity in the digestive tract of the conscious cat

1982 ◽  
Vol 48 (1) ◽  
pp. 129-135 ◽  
Author(s):  
Maurice Roche ◽  
Lionel Bueno ◽  
Monique Vagne ◽  
Christian Blourde
Keyword(s):  
Small Intestine ◽  
Electrical Activity ◽  
Digestive Tract ◽  
Slow Wave ◽  
Slow Waves ◽  
Fasting State ◽  
Bipolar Electrodes ◽  
Adult Cats ◽  
Spike Bursts ◽  
Spiking Activity

1. Bipolar electrodes were permanently implanted on the gastric antrum, and on the different portions of the small intestine of each of eleven healthy adult cats receiving one meal daily. All parts of the feline gut exhibited, as in several other species, regular slow waves and alternate periods of quiescence and electrical spiking activity during the recording sessions lasting from 10 to 30 d.2. Patterns of electrical activity characteristic of this species were identified. Both the amplitude and frequency of the antral slow-wave were related to the presence cf superimposed spike bursts during fasting decrease in the antral slow-wave frequency and increase in the length of the duodenal plateau of slow waves after the daily meal were related to its nature.3. In fasted state, the electrical spiking activity of the small intestine occurred as fused spike bursts of large amplitude potentials migrating slowly over short distances only 24 h after feeding. They are interspersed with short periods of irregular spiking activity.4. These findings suggested that, except the distal part of the small intestine which showed an activity which resembled partially the migrating myoelectric complex observed in other species during the fasting state, the motility patterns of the digestive tract in the cat were not comparable to those observed in the dog or sheep. In the cat, mixing of the contents seemed to result from more or less regular spiking activity allowing their propulsion distally. The propagation over distances varying from 200 to 1000 mm of nine to eighteen daily fused spike bursts in the fasting state remains unclear but they are related to the digestive function in accordance with the displacement aborally of their origin in a prolonged fasting condition.

GASTROINTESTINAL HYPOMOTILITY IN MAGNESIUM-DEFICIENT SHEEP

1980 ◽  
Vol 60 (2) ◽  
pp. 293-301 ◽  
Author(s):  
L. BUENO ◽  
J. FIORAMONTI ◽  
E. GEUX ◽  
Y. RAISSIGUIER
Keyword(s):  
Small Intestine ◽  
Gastrointestinal Tract ◽  
Electrical Activity ◽  
Digestive Tract ◽  
Experimental Period ◽  
Proximal Colon ◽  
Slow Waves ◽  
Deficient Diet ◽  
Intravenous Infusions ◽  
Spiking Activity

The electrical activity of the gastrointestinal tract and gallbladder was recorded in four sheep fed a Mg-deficient diet during 10 to 15 days. The mitigating effect of intravenous infusions of MgCl2 was tested at the end of the experimental period in animals presenting hypomagnesemia. Motility of the reticulo-rumen remained unchanged in Mg-deficient sheep except that there was no postprandial increased frequency of contractions. By contrast, the contractions of gallbladder, cecum and proximal colon were reduced in both amplitude and frequency. The amplitude but not the frequency of the antro-duodenal slow-waves was reduced. The amplitude of the regular spiking activity of the small intestine was reduced as well as the number of complexes produced per day. The activity of the spiral colon was correlated to the blood magnesium concentrations but Mg infusion was unable to restore immediately the motor profile of the rest of the gut to its intitial level. This was done within 2–3 days by changes in the diet in three of the four animals. It is concluded that the motility of the whole digestive tract, including the reticulo-rumen, is modified on a Mg-deficient diet and that hypomagnesemia, involved in the atony of the spiral colon, is only one of the factors responsible for the hypomotility.

Effect of secretin on electrical activity of small intestine

1975 ◽  
Vol 229 (2) ◽  
pp. 484-488 ◽  
Author(s):  
AK Mukhopadhyay ◽  
LR Johnson ◽  
EM Copeland ◽  
NW Weisbrodt
Keyword(s):  
Small Intestine ◽  
Small Bowel ◽  
Electrical Activity ◽  
Slow Wave ◽  
Intravenous Infusion ◽  
Action Potentials ◽  
Slow Waves ◽  
Wave Frequency ◽  
Conscious Dogs ◽  
Total Percentage

The effect of intravenously administered secretin (0.5, 2.0, 6.0 U/kg-h) and intraduodenal acidification (13.2 meq/h HCl) on the electrical activity of the small bowel of three conscious dogs with gastric and duodenal cannulas was observed. Electrical activity was recorded in fasted as well as fed conditions through silver wire electrodes implanted along the entire length of the small bowel. Intravenous infusion of secretin in all dosages and in all dogs delayed the onset of the interdigestive myoelectric complex and reduced the total percentage of slow waves with superimposed spike potentials. Intraduodenal acidification also inhibited the interdigestive myoelectric complex, which developed incompletely with fewer action potentials on slow waves. Secretin did not produce any alteration in the fed pattern of activity, slow-wave frequency, or the caudal migration of the interdigestive myoelectric complex. The present study indicates that the nuerohumoral mechanisms responsible for initiation of the interdigestive myoelectric complex may be different from those responsible for its caudal migration.

Migrating spike complex in the small intestine of the fasting cat

1993 ◽  
Vol 265 (4) ◽  
pp. G619-G627
Author(s):  
W. C. De Vos
Keyword(s):  
Small Intestine ◽  
Action Potential ◽  
Electrical Activity ◽  
Slow Wave ◽  
Close Association ◽  
Slow Waves ◽  
Wave Frequency ◽  
Laboratory Animals ◽  
Variable Frequency ◽  
Implanted Electrodes

This study characterizes the migrating spike complex (MSC) in the small intestine of the awake fasting cat and compares the MSC with interdigestive activity in the small intestine of other species. Electrical activity in each of 12 cats with implanted electrodes showed MSCs, bands of spike potentials which attenuated slow-wave frequency and amplitude as the MSCs progressed distally. MSCs occurred at variable frequency with intervals ranging from < 1 min to > 5 h and averaged 51.2 +/- 2.8 (SE) min. MSCs migrated at 1-8 mm/s, accelerating distally; the duration decreased distally such that the length of the bowel in a burst (2-3 cm proximally) was conserved. The MSC was associated with an intense prolonged contraction of duration similar to that of the MSC. Sometimes the MSCs occurred in close association, and when an MSC period was < 5.7 min, the second MSC propagated at a slower rate than the first. Frequently, a brief series of slow wave-associated spikes preceded an MSC. MSCs were not associated with slow waves. The MSC differs in several respects from the migrating myoelectric complex of other laboratory animals and is more appropriately classified in a category that includes giant migrating spikes, prolonged propagated contractions, power contractions, and migrating action potential complexes.

THE RELATIONSHIP BETWEEN ELECTRICAL AND MECHANICAL ACTIVITY OF THE SMALL INTESTINE OF DOG AND MAN

1960 ◽  
Vol 38 (7) ◽  
pp. 777-801 ◽  
Author(s):  
E. E. Daniel ◽  
B. T. Wachter ◽  
A. J. Honour ◽  
A. Bogoch
Keyword(s):  
Small Intestine ◽  
Electrical Activity ◽  
Slow Wave ◽  
Action Potentials ◽  
Extracellular Fluid ◽  
Slow Waves ◽  
Mechanical Activity ◽  
Electrical Currents ◽  
Bipolar Recording ◽  
Balloon Distention

Electrical activity of the small intestine of man and of dogs has been studied using monopolar recording techniques and spread of electrical activity in the small intestine of the dog using a bipolar recording technique. Motility was studied simultaneously. Electrical activity consisted of slow waves and action potentials which occurred when contractions were present. Action potentials were not conducted but slow waves sometimes spread aborally for short distances. Particular attention was paid to the relation of slow waves to action potentials and to motility. No consistent alteration in the frequency or configuration of slow waves was found associated with the occurrence of action potentials and motility, although serotonin or epinephrine altered slow wave frequency slightly. Slow waves usually were increased in amplitude during periods when motility and action potentials were occurring (during eating or balloon propulsion; after the administration of serotonin, neostigmine, physostigmine, or morphine). Slow wave amplitudes usually were diminished when motility was inhibited (by balloon distention; after administration of epinephrine, etc.). Action potentials tended to occur in phase with the slow waves, when the muscle electrode was positive relative to the indifferent electrode, but this was not always so during nonpropulsive contractions. There was also a correlation between the occurrence of distal spread of slow waves over the duodenum and upper jejunum and the ability of the intestine in this region to respond to balloon distention by propulsion.In the dog, body temperature consistently affected slow waves. A decrease of 10 °C diminished their frequencies to less than one-half and diminished their amplitude. Slow waves occurred at similar frequencies and with regular conduction after large doses of nicotine or atropine. Dibenzyline, dichloroisopropyl-norepinephrine, and vagotomy did not markedly alter slow wave frequencies. These findings and those in our studies with microelectrodes indicate that the slow waves are myogenic in origin, and represent electrical currents in the extracellular fluid initiated by periodic depolarizations of muscle cells of the small intestine.

Electrical activity of intestine recorded with pressure electrode

1961 ◽  
Vol 201 (1) ◽  
pp. 209-212 ◽  
Author(s):  
Alex Bortoff
Keyword(s):  
Small Intestine ◽  
Membrane Potential ◽  
Electrical Activity ◽  
Slow Wave ◽  
Spike Activity ◽  
Intestinal Motility ◽  
Wave Activity ◽  
Slow Waves ◽  
Reverse Effect ◽  
Naturally Occurring

The effects of certain autonomic and metabolic drugs on the electrical activity of the small intestine have been investigated, using the pressure electrode. Epinephrine inhibits spike activity and increases the membrane potential, without apparently altering the size of the slow waves. Acetylcholine has the reverse effect. The hyperpolarization produced by epinephrine is followed by a gradual depolarization which exceeds that of the membrane prior to its addition; this is not accompanied by the reappearance of spike activity. Large concentrations of epinephrine produce a waxing and waning of the amplitude of the slow waves. During inhibition by dinitrophenol, both acetylcholine and epinephrine can initiate slow wave activity. An explanation of naturally occurring waxing and waning is suggested, together with a mechanism relating the activity of the two muscle layers during normal intestinal motility.

THE RELATIONSHIP BETWEEN ELECTRICAL AND MECHANICAL ACTIVITY OF THE SMALL INTESTINE OF DOG AND MAN

1960 ◽  
Vol 38 (1) ◽  
pp. 777-801 ◽  
Author(s):  
E. E. Daniel ◽  
B. T. Wachter ◽  
A. J. Honour ◽  
A. Bogoch
Keyword(s):  
Small Intestine ◽  
Electrical Activity ◽  
Slow Wave ◽  
Action Potentials ◽  
Extracellular Fluid ◽  
Slow Waves ◽  
Mechanical Activity ◽  
Electrical Currents ◽  
Bipolar Recording ◽  
Balloon Distention

Electrical activity of the small intestine of man and of dogs has been studied using monopolar recording techniques and spread of electrical activity in the small intestine of the dog using a bipolar recording technique. Motility was studied simultaneously. Electrical activity consisted of slow waves and action potentials which occurred when contractions were present. Action potentials were not conducted but slow waves sometimes spread aborally for short distances. Particular attention was paid to the relation of slow waves to action potentials and to motility. No consistent alteration in the frequency or configuration of slow waves was found associated with the occurrence of action potentials and motility, although serotonin or epinephrine altered slow wave frequency slightly. Slow waves usually were increased in amplitude during periods when motility and action potentials were occurring (during eating or balloon propulsion; after the administration of serotonin, neostigmine, physostigmine, or morphine). Slow wave amplitudes usually were diminished when motility was inhibited (by balloon distention; after administration of epinephrine, etc.). Action potentials tended to occur in phase with the slow waves, when the muscle electrode was positive relative to the indifferent electrode, but this was not always so during nonpropulsive contractions. There was also a correlation between the occurrence of distal spread of slow waves over the duodenum and upper jejunum and the ability of the intestine in this region to respond to balloon distention by propulsion.In the dog, body temperature consistently affected slow waves. A decrease of 10 °C diminished their frequencies to less than one-half and diminished their amplitude. Slow waves occurred at similar frequencies and with regular conduction after large doses of nicotine or atropine. Dibenzyline, dichloroisopropyl-norepinephrine, and vagotomy did not markedly alter slow wave frequencies. These findings and those in our studies with microelectrodes indicate that the slow waves are myogenic in origin, and represent electrical currents in the extracellular fluid initiated by periodic depolarizations of muscle cells of the small intestine.

Intraluminal lipids modulate avian gastrointestinal motility

1995 ◽  
Vol 269 (2) ◽  
pp. R445-R452 ◽  
Author(s):  
V. Martinez ◽  
M. Jimenez ◽  
E. Gonalons ◽  
P. Vergara
Keyword(s):  
Small Intestine ◽  
Oleic Acid ◽  
Gastric Emptying ◽  
Electrical Activity ◽  
Transit Time ◽  
Gastrointestinal Motility ◽  
Phase Iii ◽  
Intestinal Transit Time ◽  
Speed Of Propagation ◽  
Spike Bursts

Infusion of lipids into the ileum delays gastric emptying and intestinal transit time in some species. The aim of this study was to characterize the actions of intraluminal lipid infusion on gastrointestinal electrical activity in chickens. Animals were prepared for electromyography with chronic electrodes in stomach, duodenum, and small intestine. Two catheters were chronically placed in the esophagus and ileum to infuse equimolar doses of either oleic acid (OA) or triolein (TO). Both OA and TO, esophageally infused, inhibited the frequency of the gastroduodenal cycle and increased the frequency of antiperistaltic spike bursts in the duodenum. Ileal infusion of OA, but not of TO, produced the same effects. Both esophageal and ileal OA infusion increased the duration of the migrating myoelectric complex (MMC) and decreased the speed of propagation of phase III. In conclusion, intraluminal infusion of lipids modulates gastrointestinal motility by decreasing the frequency of the gastric cycle, increasing duodenogastric refluxes, and elongating the MMC. These actions could delay gastric emptying and increase transit time, which suggests the presence of an "ileal brake" mechanism similar to that described in mammals.

scholarly journals Abnormal gastric slow waves in patients with functional dyspepsia assessed by multichannel electrogastrography

2001 ◽  
Vol 280 (6) ◽  
pp. G1370-G1375 ◽  
Author(s):  
Xuemei Lin ◽  
Jiande Z. Chen
Keyword(s):  
Wave Propagation ◽  
Functional Dyspepsia ◽  
Slow Wave ◽  
Single Channel ◽  
Slow Waves ◽  
Lower Percentage ◽  
Healthy Controls ◽  
Fasting State ◽  
Gastric Slow Wave ◽  
Gastric Slow Waves

The aim of this study was to utilize multichannel electrogastrography to investigate whether patients with functional dyspepsia had impaired propagation or coordination of gastric slow waves in the fasting state compared with healthy controls. The study was performed in 10 patients with functional dyspepsia and 11 healthy subjects. Gastric myoelectrical activity was measured by using surface electrogastrography with a specially designed four-channel device. The study was performed for 30 min or more in the fasting state. Special computer programs were developed for the computation of the propagation and coupling of the gastric slow wave. It was found that, compared with the healthy controls, the patients showed a significantly lower percentage of slow wave propagation (58.0 ± 8.9 vs. 89.9 ± 2.6%, P < 0.002) and a significantly lower percentage of slow wave coupling (46.9 ± 4.4 vs. 61.5 ± 6.9%, P < 0.04). In addition, the patients showed inconsistencies in the frequency and regularity of the gastric slow wave among the four-channel electrogastrograms (EGGs). It was concluded that patients with functional dyspepsia have impaired slow wave propagation and coupling. Multichannel EGG has more information than single-channel EGG for the detection of gastric myoelectrical abnormalities.

Chronic electrical activity of cat intestine

1984 ◽  
Vol 246 (4) ◽  
pp. G335-G341 ◽  
Author(s):  
A. Bortoff ◽  
L. F. Sillin ◽  
A. Sterns
Keyword(s):  
Electrical Activity ◽  
Slow Waves ◽  
Intestinal Anastomoses ◽  
Bipolar Electrodes ◽  
Spontaneous Electrical Activity ◽  
Central Origin ◽  
Variable Duration

Spontaneous electrical activity was recorded with bipolar electrodes from the gastrointestinal tracts of unanesthetized fasted cats (upper and lower cut-off frequencies: 35 and 3 Hz). In addition to slow waves (SWs) and spike potentials (SPs), the following three patterns of activity were recorded that are not observed in vitro. 1) Intense bursts of SPs (migrating spike complexes, MSCs) migrate caudally at a velocity of approximately 1 mm/s. MSCs resemble migrating myoelectric complexes (MMCs) in their velocity and by their traversal of intestinal anastomoses. SWs are usually suppressed during and immediately after the MSC, and, on their return, propagate at a higher velocity than they do prior to the MSC. Unlike its effect on MMCs, motilin does not appear to elicit MSCs, a finding consistent with the fact that MSCs occur infrequently in the duodenum and not at all in the antrum. 2) Bursts of SPs are found in the absence of recorded SWs. The SP bursts are of variable duration and occur virtually simultaneously at several recording sites, or propagate at 1-2 cm/s in either direction along the jejunum. The more usual caudally propagating SPs occur when SWs reappear. 3) "Minute rhythms," periods of spiking SWs, occur simultaneously over long lengths of upper bowel, sometimes including antrum, at intervals of about 1-2 min. It is proposed that, despite their differences, the cat MSC may be the functional counterpart of the MMC, that cat SWs are not omnipresent, and that the minute rhythms described here are of central origin.

Selective lesioning of interstitial cells of Cajal by methylene blue and light leads to loss of slow waves

1994 ◽  
Vol 266 (3) ◽  
pp. G485-G496 ◽  
Author(s):  
L. W. Liu ◽  
L. Thuneberg ◽  
J. D. Huizinga
Keyword(s):  
Methylene Blue ◽  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Electrical Activity ◽  
Slow Wave ◽  
Interstitial Cells Of Cajal ◽  
Wave Activity ◽  
Slow Waves ◽  
Slow Wave Activity ◽  
Cells Of Cajal

Incubation with 50 microM methylene blue (MB) and subsequent intense illumination resulted in abolition of the slow-wave activity in the submuscular interstitial cells of Cajal-circular muscle (ICC-CM) preparations of canine colon. This was often accompanied by a decrease in resting membrane potential. Repolarization of cells back to -70 mV did not restore the slow-wave activity, indicating that MB plus light directly interrupted the generation mechanism of slow waves. After MB incubation, a 2-min illumination consistently changed the mitochondrial conformation in ICCs from very condensed to orthodox, without inducing any obvious changes in smooth muscle cells. After 4- to 10-min illumination, ICCs became progressively more damaged with swollen and ruptured mitochondria, loss of cytoplasmic contrast and detail, loss of caveolae, and rupture of the plasma membrane. No damage was seen in smooth muscle cells or nerves. Gap junctional ultrastructure was preserved. Intense illumination without preincubation with MB left the slow waves and the ultrastructure of ICC-CM preparations unaffected. In CM preparations, without the submuscular ICC-smooth-muscle network, MB plus light induced no changes in electrical activity. We conclude that the correlation between selective damage to the submuscular ICCs (relative to smooth muscle) and selective loss of the slow-wave activity (relative to other electrical activity of the CM) strongly indicates that the ICCs play an essential role in the generation of slow waves.

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