Gastrointestinal hormone receptors on isolated smooth muscle cells from gastric antrum of the rabbit

Moummi, Chafiq; Magous, Richard; Balì, Jean-Pierre

doi:10.1016/0006-2952(89)90447-4

Cited by 26 publications

(21 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Several studies have suggested that the main pathway of motilininduced gastrointestinal contractions is different in each spe- cies. For example, in vitro contractility studies with smooth muscle strips of the rabbit upper small intestine demonstrated that contractile effects of motilin were mediated through a direct action on smooth muscle cells (36), and isolated smooth muscle cells from the rabbit antrum were contracted by superfusion with motilin (29). In contrast, in the dog, no contractile effects could be obtained with porcine motilin treatment in gastric smooth muscle preparations (6), and endogenous and exogenous motilin induced phase III contractions through a myenteric plexus and vagal pathway (28).…”

Section: Discussionmentioning

confidence: 99%

Physiological characteristics of gastric contractions and circadian gastric motility in the free-moving conscious house musk shrew (Suncus murinus)

Sakahara

Xie

Koike

et al. 2010

American Journal of Physiology-Regulatory, Integrative and Comp

View full text Add to dashboard Cite

Physiological characteristics of gastric contractions and circadian gastric motility in the free-moving conscious house musk shrew (Suncus murinus). Am J Physiol Regul Integr Comp Physiol 299: R1106 -R1113, 2010. First published August 4, 2010 doi:10.1152/ajpregu.00278.2010.-Although many studies have demonstrated the physiological action of motilin on the migrating motor complex, the precise mechanisms remain obscure. To obtain new insights into the mechanisms, we focused on the house musk shrew (Suncus murinus, suncus used as a laboratory name) as a small model animal for in vivo motilin study, and we studied the physiological characteristics of suncus gastrointestinal motility. Strain gauge transducers were implanted on the serosa of the gastric body and duodenum, and we recorded gastrointestinal contractions in the free-moving conscious suncus and also examined the effects of intravenous infusion of various agents on gastrointestinal motility. During the fasted state, the suncus stomach and duodenum showed clear migrating phase III contractions (intervals of 80 -150 min) as found in humans and dogs. Motilin (bolus injection, 100-300 ng/kg; continuous infusion, 10-100 ng · kg Ϫ1 · min Ϫ1 ) and erythromycin (80 g·kg Ϫ1 · min Ϫ1 ) induced gastric phase III contractions, and motilin injection also increased the gastric motility index in a dose-dependent manner (P Ͻ 0.05, vs. saline). Pretreatment with atropine completely abolished the motilin-induced gastric phase III contractions. On the other hand, in the free-feeding condition, the suncus showed a relatively long fasting period in the light phase followed by spontaneous gastric phase III contractions. The results suggest that the suncus has almost the same gastrointestinal motility and motilin response as those found in humans and dogs, and we propose the suncus as a new small model animal for studying gastrointestinal motility and motilin in vivo.suncus; migrating motor complex; motilin; ghrelin; gastric motility DURING A FASTED STATE, THE stomach and small intestine undergo a temporally coordinated cyclic motor pattern known as migrating motor complex (MMC) in dogs (38) and humans (44). It has been established that these coordinated contractions consist of three phases, phase I (period of motor quiescence), phase II (period of preceding irregular contractions), and phase III (period of clustered potent contractions), and the MMC is stimulated by endogenous motilin that is released in the fasted state.Motilin was originally purified from porcine intestinal mucosa in the 1970s, and its molecular structure was determined to be a 22-amino-acid polypeptide. It has been demonstrated that plasma motilin is released at ϳ100-min intervals at the interdigestive state (20,21). Physiological study of motilin in vivo has been mainly performed by using dogs and humans, and endogenous motilin and exogenous motilin have been shown to induce phase III contractions through the cholinergic pathway because atropine pretreatment completely abolished the motilin-induced contra...

show abstract

Section: Discussionmentioning

confidence: 99%

Physiological characteristics of gastric contractions and circadian gastric motility in the free-moving conscious house musk shrew (Suncus murinus)

Sakahara

Xie

Koike

et al. 2010

American Journal of Physiology-Regulatory, Integrative and Comp

View full text Add to dashboard Cite

show abstract

“…In circular muscle (constituting two-thirds of the antral muscle), the PLC enzymes exhibit a higher affinity for phosphatidylinositol monophosphate (PIP) and bisphosphate (PIP2) and thus preferentially catalyse the formation of inositol triphosphate InsP3 (Murthy and Makhlouf 1991). The events linking InsP3 to [Ca 2+ ] i increase and contraction are well documented (Moummi et al 1989;Murthy and Makhlouf 1991;Rodier et al 1999). In our culture medium, which is devoid of growth factors, CCh (0.1 mM) induced a twofold increase in InsP3 production at day 3.…”

Section: Discussionmentioning

confidence: 92%

“…We have therefore stimulated our primary culture cells grown in D-stim medium with three different agonists: the neurotransmitter carbachol (CCh) and the gastrointestinal hormones gastrin-17 and glicentin. These agents have previously been shown to induce contraction of freshly isolated antral cells (Moummi et al 1989;Rodier et al 1999). The contractile response of cultured cells to CCh was tested at day 3 and day 6.…”

Section: Carbachol Gastrin-17 and Glicentin Induce Contraction Of Cementioning

confidence: 99%

Cultured gastrointestinal smooth muscle cells: cell response to contractile agonists depends on their phenotypic state

Jarrousse

Lods

Michel

et al. 2004

Cell and Tissue Research

Self Cite

View full text Add to dashboard Cite

In the digestive tract, the transit of ingested food induces a local contraction-relaxation reflex of which the smooth muscle cell (SMC) represents the functional unit. Although freshly isolated SMCs have been extensively used for in vitro studies, in specific cases cultured cells appear necessary. Because conventionally cultured SMCs lose their contractile properties, we have developed: (1) differentiated, contractile rabbit gastric SMCs (D-stim cells), cultured in a medium supplemented with insulin, and (2) proliferative, dedifferentiated rabbit gastric SMCs (P-stim cells), cultured in a medium supplemented with insulin, fetal serum, EGF and b-FGF. The proliferative index was 5 +/- 4% and 82 +/- 10%, respectively, for D-stim and P-stim cells. Expression of SM-myosin heavy chain was observed in 90% of D-stim cells, whereas it was progressively lost in P-stim cells. Carbachol (1-100 nM), glicentin (2 nM) and gastrin-17 (100 nM) induced contraction of D-stim cells cultured for 3 or 6 days, whereas they did not induce the contraction of P-stim cells; in contrast, gastrin-17 (10 nM) was able to stimulate DNA synthesis (1.86 +/- 0.09-fold increase) in P-stim cells. The coupling of muscarinic receptors to intracellular transduction pathways was evaluated in D-stim cells: at day 3, carbachol (100 nM) induced a twofold increase in the production of inositol tri-tetra-phosphates; in parallel, a phosphorylation of ERK MAP kinases occurred within 1 min of carbachol stimulation. In conclusion, cultured functional myocytes derived from mature tissue may be used for long-term studies concerning the events coupled either to proliferation or to motility regulation of differentiated SMCs due to the activation of G-protein-coupled receptors.

show abstract

“…On the contrary, the CCK-induced contraction was insensitive to the removal of extracellular Ca2+ in our experiments. It was previously shown that CCK and ACh trigger internal Ca2+ mobilization to induce cell contraction in gastric (Makhlouf, 1987;Moummi et al 1989) and intestinal muscle (Bitar & Makhlouf, 1982a). Opposite effects of galanin and CCK8 on Ca2+ fluxes could account for the synergism we observed between these agents to induce cell contraction and thus strongly suggest that different intracellular pathways may be triggered by galanin, CCK8 and ACh.…”

Section: Discussionmentioning

confidence: 99%

“…This relaxing effect is known to be mediated through an increase of intracellular cAMP level and thus due to stimulation of adenylate cyclase (Honeyman, Merriam & Fay, 1977;Scheid, Honeyman & Fay, 1979;Gonda, Daniel, McDonald, Fox, Brooks & Oki, 1989;Moummi et al 1989). We observed a similar effect of VIP and ISO on the CCK-induced smooth muscle cell contraction in pig ileum.…”

Section: Discussionmentioning

confidence: 99%

Intracellular pathways triggered by galanin to induce contraction of pig ileum smooth muscle cells.

Botella¹,

Delvaux²,

Buéno³

et al. 1992

The Journal of Physiology

View full text Add to dashboard Cite

SUMMARY1. In order to determine the intracellular mechanisms by which galanin induces contraction of isolated smooth muscle cells from pig ileum, we examined the effects of external Ca2+, relaxing agents, pertussis toxin and forskolin on the galanininduced contraction and compared these effects to those observed on the cholecystokinin derivative CCK8-induced contraction.2. Galanin induced a concentration-dependent cell contraction. The maximal contraction (24-5 + 2 1 % of the length of resting cells) was observed at 1 nm of galanin. When cells were incubated in the simultaneous presence of concentrations of galanin (10 fM) and CCK8 (1 pM) which were ineffective alone, or galanin (10 fM) and acetylcholine (100 pM), a synergistic action was observed corresponding to a submaximal contraction.3. Incubation of cells in Ca2+-free medium caused a significant decrease in galaninbut not in CCK-induced contraction. Nifedipine, a Ca2+ channel blocker, provoked a concentration-dependent inhibition of galanin-induced contraction while it had no effect on the contraction induced by CCK8.4. Vasoactive intestinal polypeptide (VIP) and isoprenaline, known to induce cell relaxation through an increase in intracellular cAMP level, inhibited CCK-induced cell contraction at concentrations ranging from 1 pM to 1 ,IM but failed to inhibit cell contraction induced by galanin.5. When cells were pre-incubated for 3 h in the presence of 200 ng/ml of pertussis toxin, the contraction induced by galanin was abolished while the CCK-induced contraction remained unchanged. On the contrary, 10 #M forskolin abolished the contraction induced by 10 nm CCK but had no effect on galanin-induced contraction.6. These results indicate that galanin induces a concentration-dependent contraction of pig ileum smooth muscle by a direct myogenic effect. This effect of galanin involves the activation of a pertussis toxin-sensitive G protein, which results in an influx of Ca2+ into the cell. This intracellular pathway is insensitive to the relaxing effect of cAMP.

show abstract

Gastrointestinal hormone receptors on isolated smooth muscle cells from gastric antrum of the rabbit

Cited by 26 publications

References 14 publications

Physiological characteristics of gastric contractions and circadian gastric motility in the free-moving conscious house musk shrew (Suncus murinus)

Physiological characteristics of gastric contractions and circadian gastric motility in the free-moving conscious house musk shrew (Suncus murinus)

Cultured gastrointestinal smooth muscle cells: cell response to contractile agonists depends on their phenotypic state

Intracellular pathways triggered by galanin to induce contraction of pig ileum smooth muscle cells.

Contact Info

Product

Resources

About