Involvement of NO/cGMP Signaling Pathway, Ca2+ and K+ Channels on Spasmolytic Effect of Everlasting Flower Polyphenolic Extract (Helichrysum stoechas (L.) Moench).

Functional gastrointestinal diseases (FGID) are worldwide prevalent conditions. Pharmacological treatments can be ineffective, leading the population to turn to herbal or traditional remedies. Helichrysum stoechas (L.) Moench is a medicinal plant traditionally used in the Iberian Peninsula to treat digestive disorders, but its effects on gastrointestinal motility have not been scientifically demonstrated. The aim of this work was to evaluate the antispasmodic effect of a polyphenolic extract of H. stoechas (HSM), its mechanism of action and its antioxidant activity. Isometric myography studies were performed in rat ileum, and malondialdehyde (MDA) and 4-hydroxyalkenals (4-HDA) levels were measured in rat jejunum. HSM reduced the integrated mechanical activity of spontaneous contractions. In Ca2+-free medium, HSM reduced the concentration-response curve of CaCl2 similarly to verapamil. Pre-incubation with the extract blocked the contraction induced by Bay K8644, KCl and carbachol. L-NAME, ODQ, Rp-8-Br-PET-cGMPS, KT-5823, apamin, TRAM-34 and charybdotoxin reduced the relaxant effect of the extract on spontaneous contractions. MDA+4-HDA levels in LPS-treated tissue were reduced by the extract, showing antioxidant activity. In conclusion, HSM showed antispasmodic activity through inhibition of Ca2+ influx, activation of the NO/PKG/cGMP pathway and opening of Ca2+-activated K+ channels. The results suggest that H. stoechas could help in the prevention or treatment of FGIDs.

Jasonia glutinosa (L.) DC., a traditional herbal medicine, reduces inflammation, oxidative stress and protects the intestinal barrier in a murine model of colitis.

Jasonia glutinosa (L.) DC., known as rock tea (RT), is traditionally used in Spain as a digestive due to its beneficial properties in bowel disorders. The pharmacological nature of these properties has not been established yet. The aim of this work was to evaluate the therapeutic utility of RT in experimental colitis and to identify chemical constituents with anti-inflammatory and/or anti-oxidative properties. RT extract was prepared with ethanol in a Soxhlet apparatus and analysed by HPLC-DAD. Superoxide radical scavenging properties, xanthine oxidase and lipoxygenase (5-LOX) inhibitory activity, and capability to lower nitric oxide (NO) and tumor necrosis factor α (TNF-α) levels were measured in cell-free and cell-based assays. In the 2.5%-dextran-sodium sulphate (DSS) injury-repair model of ulcerative colitis (UC), mice were daily treated with sulfasalazine (SSZ, as reference drug, 100 mg/kg bw), RT (5, 25 and 50 mg/kg bw, p.o.), or vehicle over 20 days. Colitis was scored daily. Colon samples were examined macroscopically and histopathologically. Protein levels of myeloperoxidase (MPO), interleukins 6, and 10 (IL-6, IL-10), inducible NO synthase (iNOS), and cyclooxygenase-2 (COX-2) were studied as markers of oxidative stress and inflammatory activity. The integrity of the apical epithelial layer was assessed by immunofluorescence staining of zonula ocludens-1 (ZO-1). Finally, intestinal contractility was also evaluated by isometric myography. Fifteen phenolic compounds and three pigments were identified and quantified, of which caffeoylquinic acids, and the flavonoid, quercetin-3-O-galactoside, were the most abundant. RT extract significantly scavenged superoxide radicals, inhibited 5-LOX activity, and lowered NO and TNF-α levels. DSS-treated mice receiving RT scored clinically lower than controls during the first 3 days of DSS treatment and during the recovery period. SSZ was less effective than RT. Anatomical and histological examination of colon samples revealed that RT significantly prevented colon shortening, increased colon thickness, and lowered the macroscopic damage score. RT also significantly prevented the increase of MPO activity, IL-6 levels, iNOS and COX-2 expression, the loss of ZO-1 apical expression, and normalized contractility disturbances. In conclusion, daily administration of RT showed therapeutic properties in the DSS-model of UC. The benefits of RT can likely be attributed to its anti-inflammatory and antioxidant phenolic and flavonoid constituents.

NOD1 downregulates intestinal serotonin transporter and interacts with other pattern recognition receptors.

Serotonin (5-HT) is an essential gastrointestinal modulator whose effects regulate the intestinal physiology. 5-HT effects depend on extracellular 5-HT bioavailability, which is controlled by the serotonin transporter (SERT) expressed in both the apical and basolateral membranes of enterocytes. SERT is a critical target for regulating 5-HT levels and consequently, modulating the intestinal physiology. The deregulation of innate immune receptors has been extensively studied in inflammatory bowel diseases (IBD), where an exacerbated defense response to commensal microbiota is observed. Interestingly, many innate immune receptors seem to affect the serotonergic system, demonstrating a new way in which microbiota could modulate the intestinal physiology. Therefore, our aim was to analyze the effects of NOD1 activation on SERT function, as well as NOD1's interaction with other immune receptors such as TLR2 and TLR4. Our results showed that NOD1 activation inhibits SERT activity and expression in Caco-2/TC7 cells through the extracellular signal-regulated kinase (ERK) signaling pathway. A negative feedback between 5-HT and NOD1 expression was also described. The results showed that TLR2 and TLR4 activation seems to regulate NOD1 expression in Caco-2/TC7 cells. To assess the extend of cross-talk between NOD1 and TLRs, NOD1 expression was measured in the intestinal tract (ileum and colon) of wild type mice and mice with individual knockouts of TLR2, and TLR4 as well as double knockout TLR2/TLR4 mice. Hence, we demonstrate that NOD1 acts on the serotonergic system decreasing SERT activity and molecular expression. Additionally, NOD1 expression seems to be modulated by 5-HT and other immune receptors as TLR2 and TLR4. This study could clarify the relation between both the intestinal serotonergic system and innate immune system, and their implications in intestinal inflammation.

Spasmolytic effect of Jasonia glutinosa on rodent intestine.

INTRODUCTION: Jasonia glutinosa is an endemic plant species of the Iberian Peninsula and Southern France traditionally used in infusions as a spasmolytic; this plant is also known as "té de roca" (rock tea) but there is no scientific evidence about the effects of this plant. AIM: To evaluate the spasmolytic effect of rock tea. METHODS: We have studied the in vitro effect of a rock tea extract on rat duodenum spontaneous contractions and the in vivo effect on mice gastrointestinal transit. RESULTS: Rock tea extract reduced the spontaneous contractions of rat duodenal smooth muscle, inhibited KCl-induced contractions and blocked the contractions invoked by both extracellular Ca2+ and the agonist of L-type calcium channels Bay K8644. This inhibitory effect was similar to the one observed after the addition of the antagonist of L-type calcium channels verapamil. Rock tea did not modify gastrointestinal transit in healthy mice. However, after the treatment with dextran sulfate sodium, an inducer of colitis, rock tea extract reverted the increase in the gastrointestinal transit associated with this treatment. CONCLUSION: Rock tea extract relaxed duodenal smooth muscle via L-type calcium channels and normalized gastrointestinal transit in a model of colitis. These results may validate the traditional use of Jasonia glutinosa in patients with gastrointestinal alterations. Thus, rock tea may be used as a spasmolytic agent to treat gastrointestinal disorders.

Roles of Toll-Like Receptor 4, IκB Kinase, and the Proteasome in the Intestinal Alterations Caused by Sepsis.

BACKGROUND: Lipopolysaccharide decreases intestinal contractility and induces the production of cytokines, which play an important role in the pathogenesis of sepsis. AIM: The objective of the present study was to examine the role of Toll-like receptor 4, IκB kinase, and the proteasome in the intestinal alterations induced by lipopolysaccharide. METHODS: Sepsis was induced in rabbits by intravenous injection of lipopolysaccharide. Contractility studies of rabbit duodenum were performed in an organ bath. Expressions of interleukin-1ß, interleukin-6, interleukin-8, interleukin-10, IκB kinase-α, IκB kinase-ß, IκB kinase-γ, and the proteasome mRNA were determined by RT-PCR on rabbit duodenum. RESULTS: Neomycin and polymyxin B (Toll-like receptor 4 inhibitors), IKK NBD peptide (IκB kinase complex inhibitor), and MG-132 (proteasome inhibitor) blocked partially the effects of lipopolysaccharide on the acetylcholine-, prostaglandin E2-, substance P-, and KCl-induced contractions in the longitudinal and circular smooth muscle of rabbit duodenum. Lipopolysaccharide increased the mRNA expression of interleukin-6 and interleukin-8 in duodenal tissue, and this effect was partly reversed by neomycin, polymyxin B, IKK NBD peptide, and MG-132. IκB kinase-α, IκB kinase-ß, IκB kinase-γ, and the proteasome mRNA expressions was not affected by lipopolysaccharide treatment. CONCLUSIONS: Toll-like receptor 4, the IκB kinase complex, and the proteasome could be therapeutic targets in the treatment of sepsis symptoms in the intestine.

Different mechanisms of actions of genistein, quercetin on spontaneous contractions of rabbit duodenum.

Flavonoids are known to relax precontracted intestinal smooth muscle and delay intestinal transit or intestinal peristalsis. The aim of this study was to determine the effects of genistein and quercetin on spontaneous contractions of rabbit duodenum in vitro in an organ bath. Genistein and quercetin (0.1-10µM) reduced the amplitude of spontaneous contractions in the longitudinal and circular smooth muscle of rabbit duodenum, but they did not modify the frequency. Bay K8644 (L-type Ca2+ channel activator), apamin, charybdotoxin, and tetraetylammonium (K+ channel blockers) reverted the inhibition of amplitude of spontaneous contractions induced by genistein in longitudinal and circular smooth muscle. H-89 (protein kinase A inhibitor) antagonized the reduction of the amplitude of spontaneous contractions induced by quercetin in longitudinal and circular smooth muscle of duodenum, while 2,5-dideoxiadenosine (adenylyl cyclase inhibitor) reverted only the reduction of the amplitude in circular smooth muscle. In conclusion, genistein and quercetin reduce the spontaneous contractions in the duodenum by different mechanisms of actions. The effect of genistein would be mediated by Ca2+ and K+ channels, while the effect of quercetin would be mediated by cAMP and protein kinase A.

Mitogen activated protein kinases blockade improves lipopolysaccharide-induced ileal motor disturbances.

BACKGROUND: several diseases such as sepsis can affect the ileum. Lipopolysaccharide (LPS), an endotoxin present in the cell wall of gram negative bacteria, is a causative agent of sepsis. OBJECTIVES: the aims of this study were: a) to investigate the role of mitogen activated protein kinases (MAPKs) in the effect of LPS on the acetylcholine-induced contractions of rabbit ileum; and b) to study the localization of MAPKs in the ileum. MATERIAL AND METHODS: ileal contractility was studied in an organ bath and MAPKs were localized by immunohistochemistry. RESULTS: acetylcholine-induced contractions decreased with LPS. SB203580, SP600125 and U0126 blocked the effect of LPS on the acetylcholine-induced contractions. Phosphorylated p38 and ERK were detected in neurons of myenteric plexus and Phosphorylated p38 and JNK in smooth muscle cells of ileum. CONCLUSION: we can suggest that p38, JNK, and ERK MAPKs are involved in the mechanism of action of LPS in the ileum.

The Potential Role of Everlasting Flower (Helichrysum stoechas Moench) as an Antihypertensive Agent: Vasorelaxant Effects in the Rat Aorta.

Helichrysum stoechas (L.) Moench (H. stoechas) is a medicinal plant traditionally used in the Iberian Peninsula to treat different disorders such as arterial hypertension. The aim of this study was to investigate the vascular effects of a polyphenolic methanolic extract of H. stoechas, which has high antioxidant activity, and its mechanism of action. Isometric myography studies were performed in an organ bath with rat aortic rings with intact endothelium. The H. stoechas extract produced vasorelaxation in the aortic rings that were precontracted by phenylephrine or KCl. L-NAME and Rp-8-Br-PET-cGMPS but not indomethacin or H-89; it also reduced the relaxant response evoked by H. stoechas extract on the phenylephrine-induced contractions. H. stoechas extract reduced the response to CaCl2 similar to verapamil and reduced the phenylephrine-induced contractions comparable with heparin. TRAM-34, apamin and glibenclamide reduced relaxation induced by the H. stoechas extract. The combination of L-NAME+TRAM-34+apamin almost completely inhibited the H. stoechas-induced effect. In conclusion, the relaxant effect of the H. stoechas extract is partially mediated by endothelium through the activation of the NO/PKG/cGMP pathway and the opening of Ca2+-activated K+ channels. Furthermore, the decrease in the cytosolic Ca2+ by the inhibition of Ca2+ influx through the L-type Ca2+ channels and by the reduction of Ca2+ release from the sarcoplasmic reticulum via the IP3 pathway is also involved.

Nuclear factor κB is a key transcription factor in the duodenal contractility alterations induced by lipopolysaccharide.

Alterations in intestinal motility are one of the features of sepsis induced by lipopolysaccharide (LPS). This study investigated the role of the nuclear transcription factor κB (NF-κB) in the LPS-induced duodenal contractility alterations, generation of reactive oxygen species (ROS) and production of cytokines in rabbit duodenum. Rabbits were treated with saline, LPS, sulfasalazine + LPS, pyrrolidinedithiocarbamate (PDTC) + LPS or RO 106-9920 + LPS. Contractility studies were performed in an organ bath. The formation of products of oxidative damage to proteins (carbonyls) and lipids (malondialdehyde and 4-hydroxyalkenals) was quantified in intestinal tissue and plasma. The protein expression of NF-κB was measured by Western blot. The DNA binding activity of NF-κB was evaluated by transcription factor activity assay. The expression of interleukin-1ß, tumour necrosis factor α (TNF-α), interleukin-6, interleukin-10 and interleukin-8 mRNA was determined by RT-PCR. Sulfasalazine, PDTC and RO 106-9920 blocked the inhibitory effect of LPS on contractions induced by ACh in the longitudinal smooth muscle of rabbit duodenum. Sulfasalazine, PDTC and RO 106-9920 reduced the increased levels of malondialdehyde and 4-hydroxyalkenals and the carbonyls induced by LPS in plasma. Lipopolysaccharide induced the activation, translocation to the nucleus and DNA binding of NF-κB. Lipopolysaccharide increased the mRNA expression of interleukin-6 and TNF-α in duodenal tissue, and this effect was partly reversed by PDTC, sulfasalazine and RO 106-9920. In conclusion, NF-κB mediates duodenal contractility disturbances, the generation of ROS and the increase in the expression of interleukin-6 and TNF-α induced by LPS. Sulfasalazine, PDTC and RO 106-9920 may be therapeutic drugs to reduce these effects.

Contractile effect of tachykinins on rabbit small intestine.

AIM: To study the role of the tachykinin receptors in spontaneous contractions of longitudinal and circular smooth muscle from rabbit small intestine and to determine the mechanism of action of Substance P (SP). METHODS: Rabbit duodenum, jejunum and ileum segments were prepared. The spontaneous contractions of longitudinal and circular smooth muscle were recorded using a computer via an isometric force transducer. The specific agonists and antagonists of tachykinin receptors were added into the organ bath. RESULTS: The agonists of tachykinin NK1 receptor (SP and [Sar9] SP), NK2 receptor (NKA and (ß-Ala8)-NKA), and NK3 receptor (NKB and Senktide) all induced contractions in the small intestine. The contractions were diminished by NK1 receptor antagonist L-733,060, NK2 receptor antagonist GR-94800, and NK3 receptor antagonist SB 218795. Contractions caused by SP were also reduced by atropine, verapamil, PKC inhibitor staurosporine, and PLC inhibitor U73122. CONCLUSION: Ttachykinin NK1, NK2, and NK3 receptors mediate the contractions of the smooth muscle in rabbit intestine. Furthermore, SP acts directly on smooth muscle cells through the tachykinin NK1 receptor.

Trolox reduces the effect of ethanol on acetylcholine-induced contractions and oxidative stress in the isolated rabbit duodenum.

Trolox is a hydrophilic analogue of vitamin E and a free radical scavenger. Ethanol diminishes the amplitude of spontaneous contractions and acetylcholine (ACh)-induced contractions in rabbit duodenum. The aim of this work was to study the effect of Trolox on the alterations induced by ethanol on contractility and lipid peroxidation in the duodenum. The duodenal contractility studies in vitro were carried out in an organ bath and the levels of malondialdehyde and 4-hydroxyalkenals (MDA+4-HAD) were measured by spectrophotometry. Trolox increased the reduction induced by ethanol on the amplitude of spontaneous contractions in longitudinal muscle but not in circular muscle. Trolox 4 mM decreased the effects of ethanol on ACh-induced contractions and on MDA+4-HDA concentrations. We conclude that Trolox might prevent oxidative stress induced by ethanol in the duodenum.

PGE(2) receptors and their intracellular mechanisms in rabbit small intestine.

The effects of PGE(2) on longitudinal smooth muscle, the intracellular mechanisms involved, and the localization of EP receptors were investigated in rabbit small intestine. PGE(2) evoked contractions in small intestine that were reduced by tetrodotoxin and hexamethonium. 17-Phenyl trinor PGE(2), sulprostone, misoprostol and 16,16-dimethyl PGE(2) evoked contractions. Butaprost did not modify spontaneous motility. AH 6809 reduced PGE(2) and 17-phenyl trinor PGE(2)-induced contractions. Verapamil, Ca(2+) free medium, staurosporine, forskolin, theophylline, and rolipram diminished, while IP-20 and H-89 increased PGE(2)-induced contractions. Western blot analysis showed protein bands of 41kDa for EP(1), 71kDa for EP(2) and 62kDa for EP(3) receptors. EP(1), EP(2) and EP(3) receptors were detected in neurons of the myenteric and submucosal ganglia, but only EP(3) receptors were found in smooth muscle layers. This study did not detect EP(4) receptor. PGE(2)-induced contractions would be mediated through EP(1) and EP(3) receptors, and voltage-dependent Ca(2+) channels, protein kinase C, and cAMP would be implicated in these responses.

Twitch airway pressure elicited by magnetic phrenic nerve stimulation in anesthetized healthy children.

Children with diaphragm dysfunction may be unable to maintain adequate ventilation. Accurate diagnosis is important, but can only be achieved using an appropriate test and reference range. The aim of this study, therefore, was to measure diaphragm contractility and examine the influence of age and maturation, using magnetic phrenic nerve stimulation in healthy children. Anterolateral magnetic stimulation (MS) of the phrenic nerves was performed using a 43-mm figure-eight coil in 23 children (14 male; mean age, 7.8 years; range, 1.8-15.7) anesthetized for minor surgery with sevoflurane gas. The airway was maintained with a cuffed laryngeal mask airway (LMA) which was briefly occluded during MS. Diaphragm contractility was assessed by measuring the airway pressure (TwPaw) elicited by MS. TwPaw responses were obtained in all subjects, with mean (SD) TwPaw 18.2 (6.8) cm H2O bilateral, 7.3 (3.2) cm H2O left unilateral, and 8.6 (3.1) cm H2O right unilateral. Subgroup analysis was performed in 17 of the children who were prepubertal. Their mean (SD) TwPaw was 17.3 (6.8) cm H2O bilateral, 7.1 (3.7) cm H2O left unilateral, and 8.3 (3.3) right unilateral. The mean (SD) intrapatient coefficients of variation for bilateral and left and right unilateral TwPaw were 8.4% (5.2), 6.7% (3.5), and 11.7% (10.3), respectively. Bilateral and left and right unilateral TwPaw were significantly related to age (P < 0.05). In healthy prepubertal children, diaphragm contractility is primarily influenced by age.

Forearm rescue cuff improves tourniquet tolerance during intravenous regional anesthesia.

BACKGROUND AND OBJECTIVES: Tourniquet pain during intravenous regional anesthesia (IVRA) of the upper limb is common and can limit tourniquet inflation time. We hypothesize that a forearm rescue cuff is better tolerated than the traditional rescue cuff of a double-cuff tourniquet. METHODS: After Institutional Review Board (IRB) approval and informed consent, 10 healthy unmedicated volunteers took part in a prospective, randomized, cross-over study. Following inflation of the proximal tourniquet cuff on the upper arm, a standardized IVRA with 0.5% lidocaine, 0.6 mL/kg was administered. When the volunteer complained of tourniquet pain, or at 30 minutes, the initial cuff was changed to a rescue cuff. During session A, the rescue cuff was the traditional distal cuff of the double-cuff tourniquet. During session B, a single forearm cuff was used. When the volunteer experienced the same level of tourniquet pain, the rescue cuff was deflated and the study session ended. The tourniquet time for the rescue cuff, the visual analog scale (VAS) pain score, and the incidence and duration of side effects were recorded. RESULTS: The forearm rescue cuff was tolerated significantly longer than the arm rescue cuff (49 +/- 15 v 29 +/- 11 minutes, 95% confidence interval [CI] 7 to 32 minutes, P

Fast methodology of analysing major steviol glycosides from Stevia rebaudiana leaves.

The aim of this work is to propose an HPLC method for analysing major steviol glycosides as well as to optimise the extraction and clarification conditions for obtaining these compounds. Toward this aim, standards of stevioside and rebaudioside A with purities ⩾99.0%, commercial samples from different companies and Stevia rebaudiana Bertoni leaves from Paraguay supplied by Insobol, S.L., were used. The analytical method proposed is adequate in terms of selectivity, sensitivity and accuracy. Optimum extraction conditions and adequate clarification conditions have been set. Moreover, this methodology is safe and eco-friendly, as we use only water for extraction and do not use solid-phase extraction, which requires solvents that are banned in the food industry to condition the cartridge and elute the steviol glycosides. In addition, this methodology consumes little time as leaves are not ground and the filtration is faster, and the peak resolution is better as we used an HPLC method with gradient elution.

Lipopolysaccharide-induced intestinal motility disturbances are mediated by c-Jun NH2-terminal kinases.

BACKGROUND: Lipopolysaccharide (LPS) is a causative agent of sepsis. Many alterations, such as intestinal motility disturbances, have been attributed to LPS. AIMS: Here we investigated the role of c-Jun NH(2)-terminal kinases (JNK) in the effect of LPS on intestinal motility, the oxidative stress status and the cyclooxygenese-2 (COX-2) expression. METHODS: Rabbits were injected with either (1) saline, (2) LPS, (3) SP600125, a specific JNK inhibitor, or (4) SP600125+LPS. Duodenal contractility was studied in an organ bath. The formation of products of oxidative damage to proteins (carbonyls) and lipids [malondialdehyde (MDA) and 4-hydroxyalkenals (4-HDA)] was quantified by spectrophotometry in the intestine and plasma. The protein expression of p-JNK, total JNK, and COX-2 was measured by Western blot, and p-JNK was localized by immunohistochemistry. RESULTS: LPS decreased the contractions evoked by acetylcholine and prostaglandin E(2) and KCl-induced contractions. LPS increased phospho-JNK and COX-2 expressions and the levels of carbonyls and MDA+4-HDA. SP600125 blocked the effect of LPS on the acetylcholine, prostaglandin E(2), and KCl-induced contractions, the levels of carbonyls and MDA+4-HDA, and the p-JNK and COX-2 expressions. p-JNK was detected in the smooth muscle cells of duodenum. CONCLUSION: Our results suggest that JNK is involved in the mechanism of action of LPS in the intestine.

Role of TLR4 and MAPK in the local effect of LPS on intestinal contractility.

OBJECTIVES: Lipopolysaccharide (LPS) has been shown to alter intestinal contractility. Toll-like receptor 4 (TLR4), K(+) channels and mitogen-activated protein kinases (MAPKs) have been proposed to be involved in the mechanism of action of LPS. The aim of this study was to determine the role of TLR4, K(+) channels and MAPKs (p38, JNK and MEK1/2) in the local effect of LPS on the acetylcholine (ACh)-induced contractions in rabbit small intestine in vitro. METHODS: Segments of rabbit duodenum were suspended in the direction of longitudinal or circular smooth muscle fibres in a thermostatically controlled organ bath. KEY FINDINGS: LPS (0.3 µg/ml) reduced the contractions induced by ACh (100 µm) in the longitudinal and circular smooth muscle of the duodenum after 90 min of incubation. Polymyxin (TLR4 inhibitor), SB203580 (p38 MAPK inhibitor), SP600125 (JNK1/2 inhibitor) and U0126 (MEK1/2 inhibitor) antagonized the effects of the LPS on ACh-induced contractions in duodenal smooth muscle. Incubation with the blockers of K(+) channels, TEA, apamin, charybdotoxin, iberiotoxin, glibenclamide or quinine, did not reverse the effect of LPS on ACh-induced contractions. CONCLUSIONS: These results suggest that the effect of LPS on ACh-induced contractions in the rabbit duodenum might be mediated by TLR4 and p38, JNK1/2 and MEK1/2 MAPKs.

Intestinal effects of lipopolysaccharide in rabbit are mediated by cyclooxygenase-2 through p38 mitogen activated protein kinase.

The mediators of the pathophysiological symptoms of septic shock are not completely understood. The intracellular signalling mechanisms of lipopolysaccharide (LPS)-induced effects need further investigation. This study investigates (1) the role of COX-2 in the effect of LPS on (a) the KCl, acetylcholine and prostaglandin E2-induced contractions of rabbit duodenum and (b) the oxidative stress status in plasma and intestine and (2) the relationship between p38 MAPK and COX-2 expression in rabbit duodenum. Rabbits were injected i.v. with either (1) saline, (2) LPS, (3) SB203580, a p38 MAPK inhibitor, (4) SB203580+LPS, (5) NS-398, a COX-2 inhibitor or (6) NS-398+LPS. Contractility studies were performed by suspending pieces of duodenum in an organ bath in the direction of longitudinal and circular smooth muscle fibres. The formation of products of oxidative damage to proteins (carbonyls) and lipids [malondialdehyde (MDA) and 4-hydroxyalkenals (4-HDA)] was quantified in intestinal tissue and plasma. The protein expression of COX-2 was measured by western blot. The KCl, acetylcholine and prostaglandin E2-induced contractions decreased with LPS. In addition, LPS increased the levels of carbonyls and MDA+4-HDA in plasma and duodenum as well as COX-2 expression in duodenal tissue. All these effects were blocked by NS-398. The p38 MAPK inhibitor SB203580 blocked the effect of LPS on COX-2 expression. These results suggest that the effect of LPS on KCl, acetylcholine and prostaglandin E2-induced contractions in the rabbit duodenum and oxidative stress might be mediated by an increase in COX-2 expression through the p38 MAPK pathway.

Drugs errors in anaesthesia practice: four cases of non-fatal morbidity.

BACKGROUND AND OBJECTIVES: Anesthesiologists became more concerned about ensuring patient safety by a greater emphasis on outcome, quality patient care both in operation theatre and elsewhere in hospital. In the clinical practice, there is no aspect of Anesthesia that occupies a more important place in the safe management of the patients than the accurate drug administration. Medication errors represent a small part of anesthesia problems but still have potential for serious morbidity and legal consequences. The objective of this report was to describe four cases of unusual medical errors (ME) in the operation theatre, without harm to the patient, and how their analysis and identification had prevented more serious damage occurrence. CASE REPORTS: Four cases of inadvertent overdose in operation theatre previous to induction anesthesia. The same syringe was used to prepare and dilute two different drugs. This error was therefore caused by the presence of the second drug. Toxicity was manifested as brief respiratory depression and sedation, and assisted ventilation was required but no adverse outcomes happened. CONCLUSIONS: We explain how we identified the drug involved, the point at which the error occurred in order to improve clinical practice reducing medication errors. We focus on providing more information and education to each health care professional about new drugs and their preparation process, because this is should not be an acceptable practice in 2009.

Erros farmacológicos na prática anestésica: quatro casos de morbidades não fatais / Drugs errors in anaesthesia practice: four cases of non-fatal morbidity / Errores de medicación en la práctica de la anestesia: cuatro casos de morbilidad no fatal

Justificativa e objetivos: Os anestesistas estão se preocupando mais em garantir segurança aos pacientes, enfatizando o desfecho cirúrgico e qualidade do atendimento no centro cirúrgico e em outras áreas do hospital. Na prática, não existe nenhum aspecto da Anestesiologia que seja mais importante no manuseio seguro dos pacientes do que a administração correta de fármacos. Erros farmacológicos representam uma pequena percentagem dos problemas anestésicos, mas apresentam potencial de morbidade grave e consequências legais. O objetivo deste relato foi descrever quatro casos de erros medicamentosos (EM) raros no centro cirúrgico, sem consequências danosas para os pacientes e como sua análise e identificação evitaram o desenvolvimento de danos mais graves. Relato dos casos: Quatro casos de sobredoses acidentais no centro cirúrgico antes da indução anestésica. A mesma seringa foi usada para preparar e diluir dois medicamentos diferentes. Portanto, esse erro foi causado pela presença do segundo medicamento. A toxicidade se manifestou com depressão respiratória e sedação temporárias, havendo necessidade de ventilação assistida, mas sem desfechos adversos. Conclusões: Explicou-se como os medicamentos envolvidos e quando o erro cometido foram identificados para melhorar a prática clínica, reduzindo os erros medicamentosos. Enfatizamos a importância da informação e educação dos profissionais de saúde sobre novos medicamentos e seu processo de preparação, pois foi prática inaceitável em 2009.

Background and objectives: Anesthesiologists became more concerned about ensuring patient safety by a greater emphasis on outcome, quality patient care both in operation theatre and elsewhere in hospital. In the clinical practice, there is no aspect of Anesthesia that occupies a more important place in the safe management of the patients than the accurate drug administration. Medication errors represent a small part of anesthesia problems but still have potential for serious morbidity and legal consequences. The objective of this report was to describe four cases of unusual medical errors (ME) in the operation theatre, without harm to the patient, and how their analysis and identification had prevented more serious damage occurrence. Case reports: Four cases of inadvertent overdose in operation theatre previous to induction anesthesia. The same syringe was used to prepare and dilute two different drugs. This error was therefore caused by the presence of the second drug. Toxicity was manifested as brief respiratory depression and sedation, and assisted ventilation was required but no adverse outcomes happened. Conclusions: We explain how we identified the drug involved, the point at which the error occurred in order to improve clinical practice reducing medication errors. We focus on providing more information and education to each health care professional about new drugs and their preparation process, because this is should not be an acceptable practice in 2009.

Justificativas y objetivos: Los anestesiólogos están cada vez más preocupados sobre la seguridad de los pacientes, haciendo un gran énfasis en los resultados, en la cualidad de los cuidados en la salud, como también en el quirófano o en cualquier otro lugar dentro del hospital. En la práctica clínica, no existe un aspecto de la anestesia que sea más crucial en el aspecto del cuidado de la seguridad de los pacientes, que no sea la correcta administración de los fármacos. Los errores en la medicación representan una pequeña parte de los problemas de la anestesia pero todavía son un serio problema para la morbilidad, como también traen serias consecuencias legales. El objetivo de este artículo, fue describir cuatro casos de unos inusuales errores médicos (EM) en el quirófano, sin perjudicar al paciente y verificando cómo sus análisis e identificaciones pueden prevenir daños más serios. Reporte de casos: Cuatro casos de sobre dosis inadvertida en quirófano antes de la inducción de anestesia. Se usó la misma jeringuilla para la preparación y la dilución de dos fármacos diferentes. Por lo tanto, el error fue causado por la presencia del segundo fármaco. La toxicidad se manifestó con depresión y sedación temporales, necesitando ventilación asistida, no habiendo sido registrados resultados adversos. Conclusiones Hemos explicado cómo identificar los fármacos involucrados, y el punto en que ocurrió el error, en el sentido de perfeccionar la práctica clínica reduciendo los errores médicos. Nos concentramos en proveer más información y más educación de literatura médica sobre los nuevos fármacos y sobre sus procesos de preparación a cada médico, porque ésa no es una práctica aceptable en el 2009.