Search results for "Ileum"
showing 10 items of 154 documents
Mechanisms underlying the nitric oxide inhibitory effects in mouse ileal longitudinal muscle
2005
We investigated the mechanisms involved in the nitric oxide (NO)-induced inhibitory effects on longitudinal smooth muscle of mouse ileum, using organ bath technique. Exogenously applied NO, delivered as sodium nitroprusside (SNP; 0.1–100 µmol/L) induced a concentration-dependent reduction of the ileal spontaneous contractions. 1H-[1,2,4]oxadiazolol[4,3,a]quinoxalin-1-one (ODQ; 1 µmol/L), a guanilyl cyclase inhibitor, reduced the SNP-induced effects. Tetraethylammonium chloride (20 mmol/L), a non-selective K+ channel blocker, and charybdotoxin (0.1 µmol/L), blocker of large conductance Ca2+-dependent K+ channels, significantly reduced SNP-induced inhibitory effects. In contrast, apamin (0.1…
Connexin36 (Cx36) expression and protein detection in the mouse carotid body and myenteric plexus
2013
AbstractAlthough connexin36 (Cx36) has been studied in several tissues, it is notable that no data are available on Cx36 expression in the carotid body and the intestine. The present study was undertaken to evaluate using immunohistochemistry, PCR and Western blotting procedures, whether Cx36 was expressed in the mouse carotid body and in the intestine at ileum and colon level. In the carotid body, Cx36 was detected as diffuse punctate immunostaining and as protein by Western blotting and mRNA by RT-PCR. Cx36 punctate immunostaining was also evident in the intestine with localization restricted to the myenteric plexus of both the ileum and the colon, and this detection was also confirmed by…
Differential alterations in the small intestine epithelial cell turnover during acute and chronic infection with Echinostoma caproni (Trematoda)
2015
Background The intestinal epithelium plays a multifactorial role in mucosal defense. In this sense, augmented epithelial cell turnover appears as a potential effector mechanism for the rejection of intestinal-dwelling helminths. Methods A BrdU pulse-chase experiment was conducted to investigate the infection-induced alterations on epithelial cell kinetics in hosts of high (mouse) and low (rat) compatibility with the intestinal trematode Echinostoma caproni. Results High levels of crypt-cell proliferation and tissue hyperplasia were observed in the ileum of infected mice, coinciding with the establishment of chronic infections. In contrast, the cell migration rate was about two times higher …
Inhibition of the mechanical activity of mouse ileum by cactus pear (Opuntia Ficus Indica, L, Mill.) fruit extract and its pigment indicaxanthin.
2010
We investigated, using an organ bath technique, the effects of a hydrophilic extract from Opuntia ficus indica fruit pulp (cactus fruit extract, CFE) on the motility of mouse ileum, and researched the extract component(s) responsible for the observed responses. CFE (10-320 mg of fresh fruit pulp equivalents/mL of organ bath) reduced dose-dependently the spontaneous contractions. This effect was unaffected by tetrodotoxin, a neuronal blocker, N(omega)-nitro-l-arginine methyl ester, a nitric oxide synthase blocker, tetraethylammonium, a potassium channel blocker, or atropine, a muscarinic receptor antagonist. CFE also reduced the contractions evoked by carbachol, without affecting the contrac…
C1-Esterase-Inhibitor Treatment at Early Reperfusion of Hemorrhagic Shock Reduces Mesentery Leukocyte Adhesion and Rolling
2001
Objective: Complement activation probably plays a pathogenic role in multiple organ failure in shock. This study evaluates the effects of C1-esterase-inhibitor treatment on leukocyte-endothelial interaction in the mesenteric microcirculation in hemorrhagic shock. Methods: Rats underwent median laparotomy and exteriorization of an ileal loop for intravital microscopy of the mesenteric microcirculation. Volume controlled hemorrhagic shock was provoked by arterial blood withdrawal (2.5 mL/ 100 g body wt. for 60 minutes) followed by a 4-hour reperfusion period. C1-INH (100 IU/kg body wt. i.v.) or 0.9% NaCl i.v. were administered as a bolus at the beginning of reperfusion. Reperfusion time mimic…
Temperature-dependent effects of increased intraluminal pressure on serotonin release from the vascularly perfused guinea pig ileum
1987
Isolated segments of the guinea pig ileum were vascularly perfused and the release of endogenous serotonin into the portal effluent was measured. Peristalsis was induced by raising the intraluminal hydrostatic pressure by 500 Pa for 5 min. Serotonin release increased during peristalsis induced by fluid of 37 degrees C, but decreased when the temperature of the intraluminal fluid was between 13 degrees C and 22 degrees C. In the presence of naloxone (0.3 mumol/l) raising the intraluminal pressure with fluid of 37 degrees C caused an inhibition of the serotonin release which was blocked by scopolamine (0.1 mumol/l). Naloxone did not affect the inhibition of serotonin release during peristalsi…
Effects of 5-HT4 receptor stimulation on basal and electrically evoked release of acetylcholine from guinea-pig myenteric plexus
1992
The effects of 5-methoxytryptamine and 5-hydroxytryptamine (5-HT) on both basal and electrically evoked outflow of tritium were studied in guinea-pig myenteric plexus preparations preincubated with [3H]-choline. Basal outflow. 5-Methoxytryptamine caused a transient and calcium-dependent increase in basal outflow of [3H]acetylcholine that was abolished by tetrodotoxin. Ondansetron (1 μmol/1) did not affect the stimulatory response of 5-methoxytryptamine but ICS 205-930 (1 and 3 μmol/1) produced parallel rightward displacements of the concentration-response curve to 5-methoxytryptamine. The PKB value for ICS 205-930 was 6.6 suggesting an involvement of 5-HT4 receptors. 5-HT caused an increase…
Adrenergic modulation of the release of 5-hydroxytryptamine from the vascularly perfused ileum of the guinea-pig
1988
1. Isolated segments of the guinea-pig ileum were vascularly perfused and the release of 5-hydroxytryptamine (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) into the portal venous effluent was determined by h.p.l.c. with electrochemical detection. Test substances were applied via the arterial perfusion medium. 2. Isoprenaline (0.1 microM) increased the outflow of 5-HT and 5-HIAA maximally by about 75% and this was antagonized by propranolol (0.1 microM). Forskolin (1-10 microM) increased the outflow of 5-HT by approximately 105% and that of 5-HIAA by approximately 55%. The phosphodiesterase inhibitor AH 21-132 (0.1-1 microM) increased the outflow of 5-HT and 5-HIAA by about 70%. Isoprenaline…
The effects of racemic bethanechol and its (R)- and (S)-enantiomers on pre- and postjunctional muscarine receptors in the guinea-pig ileum
1985
The effect of racemic bethanechol and its (R)- and (S)-enantiomers on smooth muscle contraction and outflow of [3H]-acetylcholine were studied in the guinea-pig myenteric plexus-longitudinal muscle preparation that had been preincubated with [3H]-choline. (S)-, racemic, and (R)-bethanechol caused concentration-dependent contractions of the longitudinal muscle. The potency ratio of the strong isomer (S) to the weak one (R) was 915. Racemic and (S)-bethanechol concentration-dependently inhibited the evoked outflow of [3H]-acetylcholine. Racemic bethanechol was more potent than (S)-bethanechol. (R)-bethanechol up to a concentration of 1 mM did no affect the evoked outflow of [3H]-acetylcholine…
Regioisomeric 5(3)-aminomethyl-3(5)-phenylisoxazoles: synthesis, spectroscopic discrimination, and muscarinic activity.
1995
The regioselective synthesis of isomeric 5(3)-aminomethyl-3(5)-phenyl isoxazoles using different methods is described. Spectroscopic data, especially mass spectrometric fragmentation, were used to identify and characterize the regioisomers. The muscarinic activity of these isoxazoles was assayed on isolated guinea-pig ileum and atria as well as on isolated rabbit vas deferens. Regioisomere 5(3)-Aminomethyl-3(5)-phenyl-isoxazole: Synthese, spektroskopische Unterscheidung und muskarinische Aktivitat Es werden verschiedene Verfahren zur regioselektiven Darstellung von 5(3)-Aminomethyl-3(5)-phenyl-isoxazolen beschrieben, die anhand ihrer spektroskopischen Daten, insbesondere der massenspektrosk…