Search results for "Kinin"

Role for NK1 and NK2 receptors in the motor activity in mouse colon

2007

The present study examined the effects induced by endogenous and exogenous activation of NK(1) and NK(2) receptors on the mechanical activity of mouse proximal colon. Experiments were performed in vitro recording the changes in intraluminal pressure from isolated colonic segments. Electrical field stimulation in the presence of atropine and guanethidine produced a small relaxation, followed by nonadrenergic noncholinergic (NANC) contraction. SR140333, NK(1) receptor antagonist, or SR48968, NK(2) receptor antagonist, significantly reduced the contraction, although SR48968 appeared more efficacious. The co-administration of SR140333 and SR48968 virtually abolished the NANC contraction. [Sar(9…

Endotoxin inhibits gastric emptying in rats via a capsaicin-sensitive afferent pathway.

2001

The effects of endotoxin on gastric emptying of a solid nutrient meal and the neural mechanisms involved in such a response were investigated in conscious rats. The intraperitoneal (i.p.) administration of E. coli endotoxin (40 mug/kg) significantly reduced the 4-h rate of gastric emptying of a standard solid nutrient meal. Ablation of primary afferent neurons by systemic administration of high doses of capsaicin (20+30+50 mg/kg s.c.) to adult rats did not modify the rate of gastric emptying in control animals but prevented the delay in gastric transit induced by endotoxin. Local application of capsaicin to the vagus nerve rather than application of capsaicin to the celiac ganglion signific…

Evidence for the presence of functional protease activated receptor 4 (PAR4) in the rat colon

2004

Background and aims: Protease activated receptors (PARs) have been postulated to play a role during intestinal inflammation. The presence and role played by PAR4 in gastrointestinal functions have not been fully clarified. The aims of this study were: (i) to examine expression of PAR4 in rat proximal colon; (ii) to determine the mechanical effects induced by PAR4 activation in longitudinal muscle; and (iii) to characterise the underlying mechanisms. Methods: PAR4 expression was determined by reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry. Mechanical activity was recorded as changes in isometric tension. Results: A PCR product corresponding to the predicted…

Acetylcholine via Muscarinic Receptors Inhibits Histamine Release from Human Isolated Bronchi

1997

Human bronchi were incubated in organ baths to measure histamine release. The calcium ionophore A23187 (10 mumol/L; 1 min) stimulated histamine release by 148 +/- 28% (n = 11) above the prestimulation level but was ineffective in epithelium-denuded bronchi. Neither bradykinin (0.1 mumol/L) nor compound 48/80 (10 micrograms/ml) triggered the release of histamine from epithelium-intact bronchi. Acetylcholine did not affect spontaneous histamine release (about 2 nmol/g x 5 min) but inhibited A23187-evoked histamine release in an atropine-sensitive manner. Already a concentration as low as 0.1 nmol/L acetylcholine was effective, the maximal inhibition (by 89%) occurred at 100 nmol/L, whereas a …

Receptor phosphorylation does not mediate cross talk between muscarinic M(3) and bradykinin B(2) receptors.

1999

This study examined cross talk between phospholipase C-coupled muscarinic M3and bradykinin B2receptors coexpressed in Chinese hamster ovary (CHO) cells. Agonists of either receptor enhanced phosphoinositide signaling (which rapidly desensitized) and caused protein kinase C (PKC)-independent, homologous receptor phosphorylation. Muscarinic M3but not bradykinin B2receptors were also phosphorylated after phorbol ester activation of PKC. Consistent with this, muscarinic M3receptors were phosphorylated in a PKC-dependent fashion after bradykinin B2receptor activation, but muscarinic M3receptor activation did not influence bradykinin B2receptor phosphorylation. Despite heterologous phosphorylatio…

Micropropagation of Globe Artichoke (Cynara cardunculus L. var. scolymus).

2013

The globe artichoke (Cynara cardunculus L. var. scolymus) is a perennial plant cultivated in the Mediterranean region and the Americas for its edible young flower heads. Although vegetative propagation by offshoots or by “ovoli” (underground dormant axillary buds) has been the primary method of propagation, the potential for the diffusion of diseases and the phenotypic variability can be very high. The propagation of this species by axillary shoot proliferation from in vitro cultured meristems produces systemic pathogen free plants and a higher multiplication rate as compared to that obtained by conventional agamic multiplication. Axillary shoot proliferation can be induced from excised sho…

Postnatal overfeeding in rats leads to moderate overweight and to cardiometabolic and oxidative alterations in adulthood.

2011

In contrast to the masses of data on obesity, few data are available concerning the cardiometabolic and oxidative consequences of moderate overweight. The model of postnatal overfeeding (OF) induces an increase in body weight at weaning that remains during adult life. Litters of Wistar rats were either maintained at 12 pups (normal-fed group, NF), or reduced to 3 pups at birth in order to induce OF. At 6 months of age, metabolic parameters, circulating oxidative stress and aortic and coronary vasoreactivity were assessed. Cardiac susceptibility to ischemia-reperfusion injury was also evaluated ex vivo as were markers of cardiac remodeling. OF led to an increase in body weight at weaning (+5…

Oleanonic acid, a 3-oxotriterpene from Pistacia, inhibits leukotriene synthesis and has anti-inflammatory activity.

2001

One of the best known bioactive triterpenoids is oleanolic acid, a widespread 3-hydroxy-17-carboxy oleanane-type compound. In order to determine whether further oxidation of carbon 3 affects anti-inflammatory activity in mice, different tests were carried out on oleanolic acid and its 3-oxo-analogue oleanonic acid, which was obtained from Pistacia terebinthus galls. The last one showed activity on the ear oedema induced by 12-deoxyphorbol-13-phenylacetate (DPP), the dermatitis induced by multiple applications of 12-O-tetradecanoyl-13-acetate (TPA) and the paw oedemas induced by bradykinin and phospholipase A2. The production of leukotriene B4 from rat peritoneal leukocytes was reduced by ol…

Genotype‐phenotype correlations in Brazilian patients with hereditary angioedema due to C1 inhibitor deficiency. [Carta]

2019

Evidence for a modulatory role of cannabinoids on the excitatory NANC neurotransmission in mouse colon

2007

Abstract It is well accepted that endogenous cannabinoids and CB1 receptors are involved in the regulation of smooth muscle contractility and intestinal motility, through a mechanism mainly related to reduction of acetylcholine release from cholinergic nerve endings. Because, few data exist on a possible modulatory action of the cannabinoid agents on the non-adrenergic non-cholinergic (NANC) excitatory and inhibitory neurotransmission, the aim of the present study was to investigate the effects of cannabinoid drugs on the NANC responses elicited by electrical field stimulation (EFS) in the circular muscle of mouse proximal colon. Colonic contractions were monitored as changes in endoluminal…