Electrical and mechanical activity on longitudinal and circular layers of the human sigmoid colon were simultaneously studied. Recordings were obtained from two electrode sites spaced 3 cm apart in a piece of colon which had been resected surgically and perfused in an organ bath. Spontaneous electrical activity of the colon showed slow waves and spikes. Slow waves were present for only 24.5% and 12% of the recording time on the longitudinal and circular layers, respectively, and they appeared as localized activity which was irregular in amplitude and varying in frequency. Electrical coupling between the two muscle layers was rarely seen and slow waves were not associated with pressure changes. Spiking activity were recorded as short and long spike bursts on both muscle layers. Short spike bursts were localized activity superimposed on slow waves. The associated mechanical activity, which consisted of single weak pressure changes or prolonged contractions with summation, was determined by slow wave frequency. Long spike bursts were seen at irregular intervals and were either propagated or not propagated activity associated with electrical oscillations ranging from 24 to 46 cpm. Mechanical activity consisted of sustained tonic contractions propagated or not propagated in the same way as the electrical pattern. Coordinated electrical activity of the two muscle layers seldom occurred when spontaneous activity was being recorded. Electrical activity on both muscle layers was very sensitive to stretching and could be initiated or modulated by pharmacological agents. In particular, our findings showed that stimulation induced coordinated spiking activity on the two muscle layers and caused mechanical activity, propagated orally or aborally, which consisted of long lasting, high amplitude contractions.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetylcholine↗

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Effect of cimetidine and ranitidine on gastric electrical activity in man.

Electrical activity was recorded in six post-cholecystectomy patients using bipolar serosal electrodes. Three patients were treated with intravenous cimetidine bolus in doses of 200 mg every four hours. Another three patients were treated with intravenous ranitidine bolus in doses of 50 mg every six hours. The frequency and the amplitude of the gastric electrical control activity (ECA) and the incidence of electrical response a activity (ERA) were evaluated before and after the administration of the drugs. The administration of cimetidine and ranitidine did not produce any statistically significant variation in the frequency and amplitude of the gastric ECA and the incidence of ERA. These results show that the effects of the H2-antagonists on gastric electrical activity had no clinical relevance.

Cimetidine↗

PubMedDate not supplied

[Recovery of gastroduodenojejunal electric activity after cholecystectomy. In situ study in mam].

The recovery of gastrointestinal electrical activity--migrating myoelectrical complex (MMC) and slow waves--was studied in six women (50-77 years) after cholecystectomy for gallstones: serosal electrodes in pairs are implanted in the wall of the antrum, duodenum and jejunum during surgery. Five hour recordings were made on the first, third and fourth postoperative days (pOD), in starvation condition with hydric intake only. The recordings were made after a twelve hour fast. On the fourth postoperative day, a test meal (250 g yogurt) was given to the patients and its effects on electrical activity were recorded for 2 hours. Even though MMC were present on the first and third postoperative days, a detailed study of their origin, the length of the phase 3 and the speed of gastro-jejunal propagation showed an inhibition of gastric MMC until the fourth pOD, moreover that intestinal MMC was slower than normal until the third pOD. On the fourth postoperative day, gastric inhibition disappeared since the length of the phase 3 of the MMC in the gastric level corresponded to those of the duodenum and jejunum. Furthermore the speed of propagation corresponded to that in normal subjects. Further, the slow wave frequency peculiar to each segment studied increased progressively from the first to the fourth pOD just like the slow waves with action potentials. In conclusion, notwithstanding the presence of MMC from the first postoperative day, it was only on the fourth day that normal coordination was restored and hence that patients were able to eat again.

Action Potentials↗

PubMedDate not supplied

[Longitudinal component of gastric motility: its relationship to peristaltic velocity and contractility. Cineradiographic study in man].

The aim of this study was to further characterize the gastric longitudinal motility and its relationship between the peristaltic velocity and contractility. Twelve healthy volunteers (six made sport S and six were sedentary NS; moy +/- DS; 24 +/- 2.4 years; 172 +/- 3.9 cm; 65.8 +/- 3.4 kg; n = 12) were involved and ingested 5 hours after a standard meal, 250 ml of barium sulfate suspension. A serial of 15 fluoroscopic plates (size 10 x 10 cm) was taken in 30 seconds. For each subject, the longitudinal variation delta L (cm) of gastric shape, the mean velocity V (mm/s) of gastric peristalsis and the intensity AM (p 100) of contractile wave were measured with a digitalized table connected to a computer. Compared to NS group, the S group showed significative enhanced values of the dynamic parameters (delta L: 2.9 +/- 0.4 vs 1.8 +/- 0.2 cm; V: 2.8 +/- 0.2 vs 2.3 +/- 0.2 mm/s; AM: 55.8 +/- 5.3 vs 48.3 +/- 2.8 p 100; moy +/- DS). Faster rhythms were observed in the diagram of longitudinal motility, with or without the well known gastric frequency 3 c/min. This study allows to point out longitudinal changes of the gastric shape and shows a pattern of significant augmented gastric motility. In fact, it is necessary to consider the stomach in a biomechanical system with the diaphragm and the abdominal wall. This system influenced by exercise might be studied intensively with our dynamic parameters associated with respiratory and abdominal data.

Adult↗

PubMedDate not supplied

[Restarting of electric gastric activity in situ after a minor gastric intervention].

The restarting of the electrical gastric activity after an extramucous myotomy according to the Heller's techniques with Dor's fundoplicatio was observed in a woman by 3 pairs of electrodes implanted in the wall of the gastric fundus, corpus and antrum at 3, 11 and 20 cm from the pylorus. The electrical activity was recorded on the day of surgery and on the 1st, 3rd and 5th postoperative day. Feeding was allowed on the 5th day. The gastric frequency decreased significantly on the 1st (2.92 +/- 0.09 c/min), increased on the 3rd (3.29 +/- 0.04 c/min.) and appeared normal on the day of surgery and on the 5th day (3.10 +/- 0.09 c/min). The pattern of the Potential Pacesetter (PP) changed during the observation: it appeared with a great amplitude on the day of surgery, slowed on the 1st, was polyphasic on the 3rd and shorter and weaker on the 5th day. The spiking activity was observed on the 3rd day for 20 minutes and it allowed to establish the restoration of the normal migrating complexes. A decrease of the gastric frequency and an increase of the slow wave progression was induced by the first alimentary resumption (yoghurt). The gastric frequency increased and the velocity of the slow wave progression decreased as soon as the ingestion was over. The receptive relaxation of stomach should be related to these latter phenomena.

Action Potentials↗

PubMedDate not supplied

[Possibility of functional exploration of mastication from acoustic signals].

The chewing abnormalities are frequently evoked during odontological and medical examinations. Unfortunately, few means of investigation are available to appreciate the functional disorders. The aim of this paper was to assess masticatory parameters from observation and audiosignals of mastication with a simple analysis of records. In a first time, sixty five students (mean age = 20) applied the sugar test for the salivary capacity (dissolution time = 2 to 3 minutes). Then the chewing movements were analysed with three types (I, II, III) of salt or sweet cookies. The total duration of activity was 29.8 and 28.2 seconds respectively for the tests I and II, only 18.2 seconds for the test III. The number of cycles were 32.5, 28.1 and 19.2 mastications for respectively I, II and III tests. The later type (III) had a softer consistency than the formers. The duration Dc of masticatory cycles was constant for the same type of aliment. The values were between 0.70 for the test II and 0.90 second for the I and II ones. Signal analysis showed an important and rapid decrease of amplitude AS with an exponential-like pattern. The time constant appeared in relation with the softness. Thus, our method allows to characterize the pattern of mastication and could be used for appreciation of degrees in salivary and/or cranio-mandibular functional abnormalities.

Adult↗

PubMedDate not supplied

[Effect of 2,4-dinitrophenol on slow gastro-duodenal electrical activity. Study on the anesthetized rat].

Explore the source record for details and available documents.

Animals↗

PubMedDate not supplied

Electrogastrography: possibilities and limits.

A cutaneous electrogastrogram (EGG) is a recording of the electrical activity of the stomach by means of electrodes placed on the abdominal skin surface. Recently, there has been an increased interest in the cutaneous EGG due to the development of new recording techniques and improved methods of signal analysis, and as a result of these developments recent studies have been able to demonstrate that alterations in gastric electrical activity may be accompanied by unexplained nausea and vomiting. In spite of the diagnostic potential of the cutaneous EGG, there are numerous problems which must be resolved before widespread clinical use is possible. The authors review the current status of the cutaneous EGG and describe their own experience of its use in the study of certain organic gastric diseases.

Electrodiagnosis↗

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[Electrical activity of the intestine in the conscious dog. Simultaneous pharmacologic investigation by chronic electrodes and electroperitoneography (author's transl)].

Two technics (chronic electrodes-electrointraperitoneography : EIG) have been used simultaneously in the conscious dog for the pharmacological study of drug effects on the electrical activity of intestine. The results show a good correlation between records obtained with the technic which needs a surgical operation (chronic electrodes) and the other which doesn't (EIG). The expected effects of the parasympathomimetic (acetylcholine-neostigmine) parasympatholytic (scopolamine) and adrenergic (epinephrine-neosynephrine) drugs used on the spiking activity are obtained with the two technics.

Action Potentials↗

PubMedDate not supplied