Fabielle Angel - Academia.edu (original) (raw)
Papers by Fabielle Angel
HAL (Le Centre pour la Communication Scientifique Directe), Sep 6, 2012
Regulatory Peptides, 2013
Leptin has been shown to modulate gastrointestinal functions including nutrient absorption, growt... more Leptin has been shown to modulate gastrointestinal functions including nutrient absorption, growth, and inflammation and to display complex effects on gut motility. Leptin receptors have also been identified within the enteric nervous system (ENS), which plays a crucial role in digestive functions. Although leptin has recently been shown to activate neurons in the ENS, the precise mechanisms involved are so far unknown. Therefore, the aim of the present study was to determine the effects of leptin on rat proximal colon smooth muscle and enteric neuron activities. The effects of exogenous leptin on tone and on responses to transmural nerve stimulation (TNS) of isolated circular smooth muscle of proximal colon in rats were investigated using an organ bath technique. The effects of a physiological concentration (0.1 μM) of leptin were also studied on tone and TNS-induced relaxation in the presence of atropine, hexamethonium, L-N(G)-nitroarginine methyl ester (L-NAME) and capsazepine. Leptin caused a slight but significant decrease in tone, TNS-induced relaxation and contraction in a concentration-dependent manner in colonic preparations. Cholinergic antagonists abolished the effects of 0.1 μM leptin on TNS-induced relaxation. This concentration of leptin had no further effect on relaxation in the presence of L-NAME. In the presence of capsazepine, leptin had no further effect either on tone or relaxation compared to the drug alone. In conclusion, leptin modulates the activity of enteric inhibitory and excitatory neurons in proximal colon. These effects may be mediated through nitrergic neurons. Intrinsic primary afferent neurons may be involved.
Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology, 2008
Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 1992
ABSTRACT Is often necessary In the laboratory to realize measurements simultaneously from multipl... more ABSTRACT Is often necessary In the laboratory to realize measurements simultaneously from multiple subjects. We demonstrate here the practical feasibility of an Infrared (IR) transmission of the ECG from six dogs within a dedicated animal room : chronical recordings were made continuously to perform toxico pharmacological studies. Single channel transmitters using Interval modulation of IR pulses sent the signal to receivers placed In each cage, which was roughly separated optically from the other cages. All the transmitters and receivers were Identical : one animal was equiped Indistinctly with any transmitter, and then could be placed In any cage. This brought a new concept In biotelemetry compared to radio-frequency transmission : the system Is extremely reliable and simple to use, and provides optimal flexibility in the everyday laboratoy functionning.
Gastroentérologie clinique et biologique
The aim of our work was to determine the effects of polyamines and GABA on rat ileum motility in ... more The aim of our work was to determine the effects of polyamines and GABA on rat ileum motility in vitro. Longitudinal strips dissected from control ileum or ileum without myenteric plexus after benzalkonium chloride (BAC) treatment were placed in organ bath chambers. Spermine significantly inhibited spontaneous activity and nerve stimulation-induced response. Inhibition of spontaneous activity was not altered by BAC treatment or tetrodotoxin but was antagonized by BAY K 8644, a L-type calcium channel agonist. Spermine inhibitory effect on nerve-stimulation induced response disappeared after BAC treatment. GABA enhanced the response induced by nerve stimulation but did not antagonize spermine effects; its action was inhibited in presence of atropine and was mimicked by baclofen, a GABAB agonist. Polyamines and GABA can modulate rat ileum motility in vitro. GABA acted via neural GABAB receptors. We demonstrate for the first time that spermine exerts a dual action through different mech...
Comptes rendus des séances de la Société de biologie et de ses filiales, 1978
Post-prandial intestinal motility, analysed through two electromyographic parameters, duration of... more Post-prandial intestinal motility, analysed through two electromyographic parameters, duration of inhibition of myoelectric complex (DIMC) and percentage of spike potentials (PSP), was studied after ingestion of glucids, proteins and lipids. Post-prandial intestinal motility depends on both chemical nature and caloric load of nutriments: DICM depends on those two factors but PSP only depends on nature of nutriments. Post-prandial intestinal motility also depends on route of administration of nutriments. Intra-jejunal administration versus intra-duodenal administration increases DIMC observed for glucids and proteins, diminishes DIMC observed for lipids and diminishes PSP observed for glucids and proteins. These results indicate a specificity of intestinal post-prandial motility with characteristics of nutriments. Intestinal digestion and absorption of nutriments, just as hormonal secretion in response to intestinal passage of nutriments could explain such a specificity.
Gastroentérologie clinique et biologique, 1988
Vasopressin (VS) has been reported to stimulate colonic peristalsis in different therapeutic cond... more Vasopressin (VS) has been reported to stimulate colonic peristalsis in different therapeutic conditions. In order to determine the mechanisms involved in this effect, colonic function was studied with three different techniques staying: a) the transit time of radioopaque markers through the colon was measured in 7 healthy subjects after VS IM (0.3 U/kg of weight). A marked propulsive effect was observed. One hour after injection, 64.7 +/- 16.2 p. 100 of the markers (m +/- sem) had left the right colon vs 9.1 +/- 4.6 p. 100 after injection of NaCl (p less than 0.01) and 70.5 +/- 10.8 p. 100 of the markers emptied from the left colon vs 4.3 +/- 4.5 p. 100 after NaCl (p less than 0.01); b) an electromyographic study was carried out in 6 other healthy subjects with an intraluminal device equipped with contact electrodes, introduced into the left colon by colonoscopy. The injection of VS was followed by an increase in the number of the propagating electrical spike bursts that are known t...
Reproduction Nutrition Développement, 1981
Medical & Biological Engineering & Computing, 1982
ABSTRACT The recording of intestinal electrical activity is used to study digestive motility. Thi... more ABSTRACT The recording of intestinal electrical activity is used to study digestive motility. This activity consists of slow waves occurring at a frequency of 13–20 cycles per minute. The slow waves are sometimes superimposed with spike potentials. Different patterns of distribution of spike potentials on the slow waves have been shown to occur in physiological and pathological conditions, so that longlasting recording sessions are increasingly required. This presents the problem of analysis of large amounts of data that has not yet been resolved satisfactorily. We present herein an analogue automated system of analysis of the intestinal electrical activityin dogs. This system works in real time and provides online data recorded on a graphic recorder. A microcomputer controlled printer and tape recorder were also used. Slow waves are characterised both by the amplitude and the timing of occurrence of relative minima. The spike bursts are detected on the slow waves; their distribution on the slow waves is given, and their energy is measured. Thus, our system allows an easy analysis of long duration chronic recordings, qualitatively (distribution of the spike bursts on the slow waves) as well as quantitatively (time of occurrence of slow waves and number and energy of the spike bursts).
Objective Conflicting results showed accelerated or unchanged gastric emptying after long-term su... more Objective Conflicting results showed accelerated or unchanged gastric emptying after long-term supplementation of the diet with kaolinite, a clay used as a protective compound for the injured gut. We aimed to evaluate in conscious pigs, using scintigraphic imaging, the consequences of 4 weeks ingestion of 5% kaolinite on gastric emptying of a semi-solid meal. Since kaolinite ingestion could modify the absorption of nutrients, hence modulating duodeno-gastric reflex, we tested gastric emptying with and without duodenal infusion of lipids. Methods Eight pigs were surgically fitted with a duodenal catheter under general anaesthesia. After one week recovery, the animals were divided in two groups depending of the diet: the first group received 5% kaolinite whereas the second get an iso-caloric diet containing silicate microspheres used as an a-caloric control. After 4 weeks, two scintigraphic sessions were achieved one week apart; one with and one without Intralipid infusion (1ml.min-1 ...
Medecine & chirurgie digestives, 1980
2015 Computing in Cardiology Conference (CinC), 2015
Obtaining information about the circulatory status of a patient during resuscitation is crucial. ... more Obtaining information about the circulatory status of a patient during resuscitation is crucial. Attempts have been made toward integrating into automated external defibrillators a pulse detection algorithm based on the thoracic impedance signal. The lack of information about the hemodynamic status during out of hospital cardiac arrest (OHCA) has made the validation of such algorithms a challenging task. This study aims at proposing an annotation scheme for the assessment of pulse in OHCA. Being independent from the recording device, several databases could be annotated using the same protocol.
Hepato Gastro Oncologie Digestive, Jun 7, 1996
Differents mecanismes de modulation permettent aux fonctions digestives d'atteindre un haut d... more Differents mecanismes de modulation permettent aux fonctions digestives d'atteindre un haut degre de regulation. Il existe, en effet, une coordination complexe et efficace entre les influences endocrines, paracrines et nerveuses. Les structures anatomiques impliquees sont les differents types cellulaires localises dans la paroi digestive. L'information nerveuse sensitive et motrice peut circuler entre les differentes structures, ou effecteurs, qui sont eux-memes relies aux centres nerveux. Les circuits nerveux realises dans la paroi digestive par les fibres du systeme nerveux autonome constituent le niveau d'integration intraparietal, veritable « cerveau » qui integre des informations multiples et regle de nombreuses fonctions. Le systeme nerveux enterique est constitue de recepteurs sensitifs localises dans la muqueuse (recepteurs polymodaux) et dans la musculature lisse (mecanorecepteurs), et par les prolongements des neurones sensitifs. Ces derniers communiquent avec d'autres neurones (interneurones) par l'intermediaire de collaterales axonales. Les supports chimiques de l'information nerveuse sont les neurotransmetteurs. Ceux-ci ont fait l'objet d'un tres grand nombre de travaux qui ont mis l'accent sur la diversite de leur structure moleculaire et des recepteurs membranaires qui les lient specifiquement. Les neurones sont ainsi classes suivant la nature chimique des neurotransmetteurs qu'ils contiennent et qu'ils liberent mais, aussi selon leurs caracteristiques morphologiques et electrophysiologiques.
Chirurgie; mémoires de l'Académie de chirurgie
From the oesophagus to the rectum, the muscularis mucosae comprises a thin layer of smooth muscle... more From the oesophagus to the rectum, the muscularis mucosae comprises a thin layer of smooth muscle at the base of the digestive tract mucosa. Although the anatomic relations of the muscularis mucosae are well described, its physiological role is still only hypothesized. The muscularis mucosae could be implicated in the different functions of the digestive tract wall including absorption, secretion and protection. Modified function could be an early sign of certain pathological situations. The aim of this work was to investigate, in a dog model, the motor function of the muscularis mucosae by using an original technique for recording electromyograms and by comparing the electrical activity generated by the muscularis mucosae with the activity of the external muscle layers of the colon. We were able to demonstrate that in situ, the muscularis mucosae generates regular rhythmic electrical signals: slow wave patterns with rare episodes of rapid activity and sporadic action potentials. Th...
Gastroentérologie clinique et biologique, 1981
Comptes rendus des séances de la Société de biologie et de ses filiales, 1980
It has been well established that the electrical activity of the small intestine consists, in the... more It has been well established that the electrical activity of the small intestine consists, in the fasting state, in a cyclic phenomenon - the myoelectric complex - that recurs at about 90 minutes intervals in the dog. The myoelectric complex is disrupted by oral feeding whereas intravenous feeding does not change the cyclically recurring myoelectric activity. The aim of our work was to investigate whether intravenous ethanol was followed by changes in the myoelectric complex. 5 dogs were prepared with Ag AgCl electrodes sewn in the jejunum. After 15 days recovery, the electrical activity was recorded in the dogs fasted for 24 hours, after injection of 100% ethanol at doses of 2, 5 and 10 ml, the total volume of the solution being adjusted to 20 ml with saline. Controls were made with saline 154 mM. Each experiment was repeated twice. The effects of alcohol were studied on the 3 interdigestive cycles following injections of alcohol. The results showed that neither saline nor ethanol ...
Gastroentérologie clinique et biologique, 1978
HAL (Le Centre pour la Communication Scientifique Directe), Sep 6, 2012
Regulatory Peptides, 2013
Leptin has been shown to modulate gastrointestinal functions including nutrient absorption, growt... more Leptin has been shown to modulate gastrointestinal functions including nutrient absorption, growth, and inflammation and to display complex effects on gut motility. Leptin receptors have also been identified within the enteric nervous system (ENS), which plays a crucial role in digestive functions. Although leptin has recently been shown to activate neurons in the ENS, the precise mechanisms involved are so far unknown. Therefore, the aim of the present study was to determine the effects of leptin on rat proximal colon smooth muscle and enteric neuron activities. The effects of exogenous leptin on tone and on responses to transmural nerve stimulation (TNS) of isolated circular smooth muscle of proximal colon in rats were investigated using an organ bath technique. The effects of a physiological concentration (0.1 μM) of leptin were also studied on tone and TNS-induced relaxation in the presence of atropine, hexamethonium, L-N(G)-nitroarginine methyl ester (L-NAME) and capsazepine. Leptin caused a slight but significant decrease in tone, TNS-induced relaxation and contraction in a concentration-dependent manner in colonic preparations. Cholinergic antagonists abolished the effects of 0.1 μM leptin on TNS-induced relaxation. This concentration of leptin had no further effect on relaxation in the presence of L-NAME. In the presence of capsazepine, leptin had no further effect either on tone or relaxation compared to the drug alone. In conclusion, leptin modulates the activity of enteric inhibitory and excitatory neurons in proximal colon. These effects may be mediated through nitrergic neurons. Intrinsic primary afferent neurons may be involved.
Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology, 2008
Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 1992
ABSTRACT Is often necessary In the laboratory to realize measurements simultaneously from multipl... more ABSTRACT Is often necessary In the laboratory to realize measurements simultaneously from multiple subjects. We demonstrate here the practical feasibility of an Infrared (IR) transmission of the ECG from six dogs within a dedicated animal room : chronical recordings were made continuously to perform toxico pharmacological studies. Single channel transmitters using Interval modulation of IR pulses sent the signal to receivers placed In each cage, which was roughly separated optically from the other cages. All the transmitters and receivers were Identical : one animal was equiped Indistinctly with any transmitter, and then could be placed In any cage. This brought a new concept In biotelemetry compared to radio-frequency transmission : the system Is extremely reliable and simple to use, and provides optimal flexibility in the everyday laboratoy functionning.
Gastroentérologie clinique et biologique
The aim of our work was to determine the effects of polyamines and GABA on rat ileum motility in ... more The aim of our work was to determine the effects of polyamines and GABA on rat ileum motility in vitro. Longitudinal strips dissected from control ileum or ileum without myenteric plexus after benzalkonium chloride (BAC) treatment were placed in organ bath chambers. Spermine significantly inhibited spontaneous activity and nerve stimulation-induced response. Inhibition of spontaneous activity was not altered by BAC treatment or tetrodotoxin but was antagonized by BAY K 8644, a L-type calcium channel agonist. Spermine inhibitory effect on nerve-stimulation induced response disappeared after BAC treatment. GABA enhanced the response induced by nerve stimulation but did not antagonize spermine effects; its action was inhibited in presence of atropine and was mimicked by baclofen, a GABAB agonist. Polyamines and GABA can modulate rat ileum motility in vitro. GABA acted via neural GABAB receptors. We demonstrate for the first time that spermine exerts a dual action through different mech...
Comptes rendus des séances de la Société de biologie et de ses filiales, 1978
Post-prandial intestinal motility, analysed through two electromyographic parameters, duration of... more Post-prandial intestinal motility, analysed through two electromyographic parameters, duration of inhibition of myoelectric complex (DIMC) and percentage of spike potentials (PSP), was studied after ingestion of glucids, proteins and lipids. Post-prandial intestinal motility depends on both chemical nature and caloric load of nutriments: DICM depends on those two factors but PSP only depends on nature of nutriments. Post-prandial intestinal motility also depends on route of administration of nutriments. Intra-jejunal administration versus intra-duodenal administration increases DIMC observed for glucids and proteins, diminishes DIMC observed for lipids and diminishes PSP observed for glucids and proteins. These results indicate a specificity of intestinal post-prandial motility with characteristics of nutriments. Intestinal digestion and absorption of nutriments, just as hormonal secretion in response to intestinal passage of nutriments could explain such a specificity.
Gastroentérologie clinique et biologique, 1988
Vasopressin (VS) has been reported to stimulate colonic peristalsis in different therapeutic cond... more Vasopressin (VS) has been reported to stimulate colonic peristalsis in different therapeutic conditions. In order to determine the mechanisms involved in this effect, colonic function was studied with three different techniques staying: a) the transit time of radioopaque markers through the colon was measured in 7 healthy subjects after VS IM (0.3 U/kg of weight). A marked propulsive effect was observed. One hour after injection, 64.7 +/- 16.2 p. 100 of the markers (m +/- sem) had left the right colon vs 9.1 +/- 4.6 p. 100 after injection of NaCl (p less than 0.01) and 70.5 +/- 10.8 p. 100 of the markers emptied from the left colon vs 4.3 +/- 4.5 p. 100 after NaCl (p less than 0.01); b) an electromyographic study was carried out in 6 other healthy subjects with an intraluminal device equipped with contact electrodes, introduced into the left colon by colonoscopy. The injection of VS was followed by an increase in the number of the propagating electrical spike bursts that are known t...
Reproduction Nutrition Développement, 1981
Medical & Biological Engineering & Computing, 1982
ABSTRACT The recording of intestinal electrical activity is used to study digestive motility. Thi... more ABSTRACT The recording of intestinal electrical activity is used to study digestive motility. This activity consists of slow waves occurring at a frequency of 13–20 cycles per minute. The slow waves are sometimes superimposed with spike potentials. Different patterns of distribution of spike potentials on the slow waves have been shown to occur in physiological and pathological conditions, so that longlasting recording sessions are increasingly required. This presents the problem of analysis of large amounts of data that has not yet been resolved satisfactorily. We present herein an analogue automated system of analysis of the intestinal electrical activityin dogs. This system works in real time and provides online data recorded on a graphic recorder. A microcomputer controlled printer and tape recorder were also used. Slow waves are characterised both by the amplitude and the timing of occurrence of relative minima. The spike bursts are detected on the slow waves; their distribution on the slow waves is given, and their energy is measured. Thus, our system allows an easy analysis of long duration chronic recordings, qualitatively (distribution of the spike bursts on the slow waves) as well as quantitatively (time of occurrence of slow waves and number and energy of the spike bursts).
Objective Conflicting results showed accelerated or unchanged gastric emptying after long-term su... more Objective Conflicting results showed accelerated or unchanged gastric emptying after long-term supplementation of the diet with kaolinite, a clay used as a protective compound for the injured gut. We aimed to evaluate in conscious pigs, using scintigraphic imaging, the consequences of 4 weeks ingestion of 5% kaolinite on gastric emptying of a semi-solid meal. Since kaolinite ingestion could modify the absorption of nutrients, hence modulating duodeno-gastric reflex, we tested gastric emptying with and without duodenal infusion of lipids. Methods Eight pigs were surgically fitted with a duodenal catheter under general anaesthesia. After one week recovery, the animals were divided in two groups depending of the diet: the first group received 5% kaolinite whereas the second get an iso-caloric diet containing silicate microspheres used as an a-caloric control. After 4 weeks, two scintigraphic sessions were achieved one week apart; one with and one without Intralipid infusion (1ml.min-1 ...
Medecine & chirurgie digestives, 1980
2015 Computing in Cardiology Conference (CinC), 2015
Obtaining information about the circulatory status of a patient during resuscitation is crucial. ... more Obtaining information about the circulatory status of a patient during resuscitation is crucial. Attempts have been made toward integrating into automated external defibrillators a pulse detection algorithm based on the thoracic impedance signal. The lack of information about the hemodynamic status during out of hospital cardiac arrest (OHCA) has made the validation of such algorithms a challenging task. This study aims at proposing an annotation scheme for the assessment of pulse in OHCA. Being independent from the recording device, several databases could be annotated using the same protocol.
Hepato Gastro Oncologie Digestive, Jun 7, 1996
Differents mecanismes de modulation permettent aux fonctions digestives d'atteindre un haut d... more Differents mecanismes de modulation permettent aux fonctions digestives d'atteindre un haut degre de regulation. Il existe, en effet, une coordination complexe et efficace entre les influences endocrines, paracrines et nerveuses. Les structures anatomiques impliquees sont les differents types cellulaires localises dans la paroi digestive. L'information nerveuse sensitive et motrice peut circuler entre les differentes structures, ou effecteurs, qui sont eux-memes relies aux centres nerveux. Les circuits nerveux realises dans la paroi digestive par les fibres du systeme nerveux autonome constituent le niveau d'integration intraparietal, veritable « cerveau » qui integre des informations multiples et regle de nombreuses fonctions. Le systeme nerveux enterique est constitue de recepteurs sensitifs localises dans la muqueuse (recepteurs polymodaux) et dans la musculature lisse (mecanorecepteurs), et par les prolongements des neurones sensitifs. Ces derniers communiquent avec d'autres neurones (interneurones) par l'intermediaire de collaterales axonales. Les supports chimiques de l'information nerveuse sont les neurotransmetteurs. Ceux-ci ont fait l'objet d'un tres grand nombre de travaux qui ont mis l'accent sur la diversite de leur structure moleculaire et des recepteurs membranaires qui les lient specifiquement. Les neurones sont ainsi classes suivant la nature chimique des neurotransmetteurs qu'ils contiennent et qu'ils liberent mais, aussi selon leurs caracteristiques morphologiques et electrophysiologiques.
Chirurgie; mémoires de l'Académie de chirurgie
From the oesophagus to the rectum, the muscularis mucosae comprises a thin layer of smooth muscle... more From the oesophagus to the rectum, the muscularis mucosae comprises a thin layer of smooth muscle at the base of the digestive tract mucosa. Although the anatomic relations of the muscularis mucosae are well described, its physiological role is still only hypothesized. The muscularis mucosae could be implicated in the different functions of the digestive tract wall including absorption, secretion and protection. Modified function could be an early sign of certain pathological situations. The aim of this work was to investigate, in a dog model, the motor function of the muscularis mucosae by using an original technique for recording electromyograms and by comparing the electrical activity generated by the muscularis mucosae with the activity of the external muscle layers of the colon. We were able to demonstrate that in situ, the muscularis mucosae generates regular rhythmic electrical signals: slow wave patterns with rare episodes of rapid activity and sporadic action potentials. Th...
Gastroentérologie clinique et biologique, 1981
Comptes rendus des séances de la Société de biologie et de ses filiales, 1980
It has been well established that the electrical activity of the small intestine consists, in the... more It has been well established that the electrical activity of the small intestine consists, in the fasting state, in a cyclic phenomenon - the myoelectric complex - that recurs at about 90 minutes intervals in the dog. The myoelectric complex is disrupted by oral feeding whereas intravenous feeding does not change the cyclically recurring myoelectric activity. The aim of our work was to investigate whether intravenous ethanol was followed by changes in the myoelectric complex. 5 dogs were prepared with Ag AgCl electrodes sewn in the jejunum. After 15 days recovery, the electrical activity was recorded in the dogs fasted for 24 hours, after injection of 100% ethanol at doses of 2, 5 and 10 ml, the total volume of the solution being adjusted to 20 ml with saline. Controls were made with saline 154 mM. Each experiment was repeated twice. The effects of alcohol were studied on the 3 interdigestive cycles following injections of alcohol. The results showed that neither saline nor ethanol ...
Gastroentérologie clinique et biologique, 1978