Search results for "Kinin"
showing 10 items of 194 documents
The serum protease network—one key to understand complex regional pain syndrome pathophysiology
2019
Complex regional pain syndrome (CRPS) develops after fracture. The acute CRPS phenotype resembles exaggerated inflammation, which is explained by local and systemic activation of a proinflammatory network including peptides and cytokines. Epidemiologic data suggest that inactivation of the peptidase angiotensin-converting enzyme in patients treated for hypertension increases the odds to develop CRPS. This hint leads us to investigate the serum protease network activity in patients with CRPS vs respective controls. For this purpose, we developed a dabsyl-bradykinin (DBK)-based assay and used it to investigate patients with CRPS, as well as healthy and pain (painful diabetic neuropathy [dPNP]…
Kinin receptor status in normal and inflammed gastric mucosa
1997
No documented studies have been reported on the presence of B1 and B2 kinin receptors in the mammalian gastric mucosa. This first study aimed to immunolocalise sites of B1 and B2 kinin receptors in the human pyloric gastric mucosa and to evaluate its role in gastritis. Biopsies were obtained from patients with dyspepsia during endoscopic examination of the patient. The diagnosis and grading of the gastritis was performed on histological examination. Sections were immunostained for both B1 and B2 receptors using rabbit anti-human B1 and B2 kinin receptor antibodies. Control tissue was obtained from partial gastrectomy specimens, following surgical excision of the antrum for duodenal ulcers. …
Organogenesis and encapsulation of in vitro-derived propagules of Carrizo citrange [Citrus sinensis (L.) Osb. × Poncirius trifoliata (L.) Raf]
2011
Due to widespread polyembryony, Citrus rootstocks are usually propagated by open-pollinated seed germination, although micropropagation offers many advantages. Encapsulation technology has recently attracted the interest of researchers in the field of plant propagation because it combines the advantages of zygotic or gamic seeds with those of micropropagation. In this study, we examined the encapsulation of Carrizo citrange uninodal microcuttings (3–4 mm long) and evaluated the influence of the calcium alginate coating, a short time storage at cold temperature, and different sowing substrates on the viability and regrowth of the explants. A secondary aim was to develop an efficient protocol…
Inhibition of human detrusor contraction by a urothelium derived factor.
2003
Stimulating muscarinic receptors in pig bladder urothelium causes the release of a diffusable factor that inhibits contractions of the underlying detrusor muscle. We investigated whether the contractions of human detrusor strips elicited by the muscarinic agonist carbachol, electrical field stimulation, KCl or the neurokinin receptor agonist neurokinin A are affected by the urothelium.Paired intact and urothelium denuded muscle strips were placed in modified gassed Tyrode's solution at 37C. Cumulative concentration-response curves to carbachol or KCl were constructed. In other tissues the strips were stimulated electrically (1 to 40 Hz) with trains of square wave pulses 20 seconds in durati…
Na+ ions binding to the bradykinin B2 receptor suppress agonist-independent receptor activation.
1996
Control of the balance between receptor activation and inactivation is a prerequisite for seven transmembrane domain (7TM) receptor function. We asked for a mechanism to stabilize the inactive receptor conformation which prevents agonist-independent receptor activation. Na+ ions have reciprocal effects on agonist versus antagonist interaction with various 7TM receptors. To investigate the Na+ dependence of receptor activation we chose the bradykinin B2 receptor as a prototypic 7TM receptor. Decrease of the intracellular Na+ content from 40 mM to 10 mM of COS-1 cells transiently expressing rat B2 receptors activated the B2 receptor in the absence of agonist as shown by a 3-fold increase in t…
Involvement of tachykinin NK2 receptors in the modulation of spontaneous motility in rat proximal colon.
2000
The role of endogenous tachykinins and the mechanisms whereby they act on NK2 receptors, modulating spontaneous motility, were investigated in rat isolated proximal colon. The mechanical activity was detected as changes in intraluminal pressure. The NK2 receptor antagonist, MEN 10627, produced a concentration-dependent reduction of the contraction amplitude. [beta-Ala8]-neurokinin A(4-10), an NK2 receptor agonist, and [Sar9, Met(O2)11]-Substance P ([Sar9, Met(O2)11]-SP), an NK1 receptor agonist, induced a concentration-dependent contractile response, characterized by an increase in basal tone with superimposed phasic contractions. MEN 10627 antagonized the response to [beta-Ala8]-neurokinin…
Tachykinin NK(2) receptors facilitate acetylcholine release from guinea-pig isolated trachea.
2000
The release of newly synthesised [3H]acetylcholine was evoked by electrical field stimulation (5 Hz, 600 pulses) of epithelium-deprived guinea-pig trachea strips after sensory neuropeptides depletion with 3 microM capsaicin. The selective tachykinin NK(2) receptor agonist [betaAla(8)]neurokinin A-(4-10) increased in a concentration-dependent manner the electrically-induced release of [3H]acetylcholine. The facilitatory effect was antagonised by the selective non-peptide tachykinin NK(2) receptor antagonist, SR 48968 (apparent pK(B) 8.9). The tachykinin NK(1) and NK(3) receptor agonists substance P methyl ester and senktide (both 10 and 100 nM), respectively, did not affect the evoked releas…
Extracellular Domains of the Bradykinin B2 Receptor Involved in Ligand Binding and Agonist Sensing Defined by Anti-peptide Antibodies
1996
Many of the physiological functions of bradykinin are mediated via the B2 receptor. Little is known about binding sites for bradykinin on the receptor. Therefore, antisera against peptides derived from the putative extracellular domains of the B2 receptor were raised. The antibodies strongly reacted with their corresponding antigens and cross-reacted both with the denatured and the native B2 receptor. Affinity-purified antibodies to the various extracellular domains were used to probe the contact sites between the receptor and its agonist, bradykinin or its antagonist HOE140. Antibodies to extracellular domain 3 (second loop) efficiently interfered, in a concentration-dependent manner, with…
Characterization of sensory neurotransmission and its inhibition via alpha 2B-adrenoceptors and via non-alpha 2-receptors in rabbit iris.
1993
To find out whether, and which type of, adrenoceptors mediate prejunctional inhibition of sensory neurotransmitter release from trigeminal fibres, the modulation of twitch response to electrical field stimulation on rabbit isolated iris was investigated. Evoked iris sphincter contractions consisted of a minor fast cholinergic and a large slow component. The latter was unaffected by atropine and guanethidine, hence nonadrenergic noncholinergic in nature (NANC), but nearly completely abolished by capsaicin pretreatment and by the neurokinin receptor antagonist spantide. The response was probably not mediated by NK2 receptors as SR 48,968, an NK2 selective nonpeptide antagonist, failed to redu…
The Clinical Enzymology of the Complement System
1989
The complement (C) system is one of the most important humoral systems mediating many activities that contribute to inflammation and host defense, e.g. various anaphylatoxin activities, Chemotaxis and opsonization for phagocytosis. The C system is similar to other humoral systems, such as coagulation, fibrinolysis and the kinin system, a multifactoral system whose activation represents sequentially occurring multi-step activation cascades of the “classical” as well as the “alternative” pathway.