Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01042 (bradykinin)
 15,585 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Stimulation of the vidian nerve in the dog induced an apparent vasodilation in the mucosa of the Eustachian tube. It is presumed that these parasympathetic fibers course from the greater petrosal nerve through the vidian to the sphenopalatine ganglion. The pharyngeal nerve arises from the ganglion and innervates the mucosa of the tube. Perfusion of the dog's Eustachian tube with solutions of various osmolarities caused a shrinking or swelling of the tube mucosa. Ten percent alterations in the concentration of saline, Ringer's or isotonic KCl produced a hypo- or hypertonic effect. Systemic administration of osmotic diuretics was shown to remove water from normal and edematous tubal mucosa. An agent in human middle ear effusions was found to contract smooth muscle. The behavior of this agent in pharmacological tests suggested the presence of prostaglandins (PG). The effusions were tested for the presence of other inflammatory mediators such as bradykinin, acetylcholine and histamine. These were felt to be absent or present in small amounts. A radioimmune assay of pooled samples of middle ear effusions revealed the presence of several PG, notably PGF2alpha and PGE2. There appeared to be a higher concentration of PG in mucoid effusions than serous effusions. The inflammatory capabilities of these agents are mentioned.
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PMID:Autonomic stimulation, osmolarity and prostaglandin effects in the Eustachian tube. 126 47

The bradykinin (BK) B2 receptor cDNA was synthesized by rt-PCR and transfected into the Chinese hamster lung fibroblasts, CCL39. The CCL39 do not contain the mRNA for this receptor and do not bind BK. Clones of transfected cells were screened for BK receptor mRNA, binding of BK, and for [Ca2+]i response to BK. The clones showed various levels of receptor mRNA. Scatchard analysis of three clones, B6, B5 and B1, each gave a Kd of approximately 1.0nM while the Bmax for each clone differed at 320, 38.7, and 5.39 fmoles per 10(6) cells respectively. The [Ca2+]i response of the three clones to BK decreased with the receptor number/cell. Thus, levels of mRNA, BK binding and [Ca2+]i response proved proportionally related in the transfected clones. The actions of BK and alpha-thrombin, which has an endogenous receptor in these cells, were assessed in clone B6. BK proved active but also distinct from thrombin. BK at 10nM and thrombin at 2units/ml both effectively increased cytosolic [Ca2+]i. BK at 10nM stimulated PGE2 production three fold over basal, while thrombin only marginally elevated PGE2 levels. Alone, BK stimulated a small increase in 3H-thymidine incorporation into DNA. However, in combination with insulin, BK stimulated DNA synthesis to 76% of thrombin, a potent mitogen in these cells. These results illustrate that the BK-B2 receptor cDNA can be stably transfected into a mammalian cell and can activate transmembrane signalling pathways.
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PMID:Functional expression of the bradykinin-B2 receptor cDNA in Chinese hamster lung CCL39 fibroblasts. 128 Jan 23

The involvement of arachidonic acid and eicosanoids in glucose absorption and metabolism was investigated in isolated mouse jejunum. Characteristics of glucose absorption and its metabolic fate are reported. Reduction in the dietary precursor of arachidonic acid, linoleic acid, and inhibition of phospholipid hydrolysis with mepacrine reduced glucose absorption with no effect on metabolism, although mepacrine increased the proportion of luminal to serosal lactate release. Bradykinin and n-FMLP enhanced metabolism by 2.1- and 2.4-fold, respectively, both reducing the percentage of metabolised glucose converted to lactate, while neither influenced absorption. Both indomethacin and NDGA decreased absorption and enhanced metabolism. The percentage of metabolised glucose converted to lactate decreased and the ratio of luminal to serosal lactate release was unchanged. In the absence of inhibitors, PGE2 (5 microM) decreased absorption by 28%, metabolism by 24% and total lactate production by 32% and LTB4 (20 nM) increased only absorption by 32%. PGE2 release into the perfusates was predominantly serosal (1-10 nM) and was inhibited by indomethacin. PGE2 could not reverse the indomethacin-induced decrease in absorption, but reversed the enhancement of metabolism by 89% and total lactate production by 60%. In conclusion, while the specificity of the drug-related absorptive effects remain unclear, alterations in the utilisation of the absorbed glucose via drug-induced changes in arachidonic acid synthesis and metabolism are apparent. Furthermore, exogenous PGE2 may protect against the effects of indomethacin and itself reduces active glucose absorption, the metabolism of the absorbed glucose and the amount of lactate formed.
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PMID:Metabolism of absorbed glucose in mouse jejunum: influence of arachidonic acid, non-steroidal anti-inflammatory drugs and eicosanoids. 129 27

The endothelium-dependent (acetylcholine, bradykinin, substance P) and the endothelium-independent (gliceryl trinirate, 3-morpholinsydnominine, sodium nitroprusside) vasodilators were studied in the Langendorff-perfused heart of the guinea pig. The involvement of prostanoids and EDRF in the endothelium-dependent responses were assessed by using indomethacin, an inhibitor of cyclooxygenase, and NG-nitro-L-Arginine, an inhibitor of NO synthase. The endothelium-independent agents were used as reference compounds. Both indomethacin and NG-nitro-L-Arginine elevated significantly baseline coronary perfusion pressure, indicating that prostanoids (most likely PGI2 and PGE2) and EDRF modulate the resting tone of the guinea pig coronary circulation. NG-nitro-L-Arginine, but not indomethacin, considerably reduced receptor-stimulated responses. It is concluded that acetylcholine, bradykinin or substance P-induced vasodilation is mediated by EDRF. In contrast, prostanoids do not contribute to endothelium-dependent responses. In addition, short-term tachyphylaxis to bolus injection of gliceryl trinitrate but not of sodium nitroprusside was demonstrated, suggesting that this preparation may be of value for studying nitrate tolerance.
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PMID:The endothelium-dependent and the endothelium-independent vasodilators in the isolated, perfused guinea pig heart. 129 66

The paracrine and intracellular mechanisms controlling stromal cell growth in the normal or neoplastic breast are unknown. This in vitro study uses human breast fibroblasts to investigate a potential role for the inflammatory peptide mediator bradykinin (BK) in the regulation of DNA synthesis and signal transduction in these cells. Bradykinin stimulated a dose-dependent increase in inositol lipid hydrolysis and cytosolic Ca2+ levels in serum-starved fibroblasts derived from both normal and breast tumor tissue. Bradykinin also caused a dose-dependent decrease in cell growth and [3H]thymidine incorporation into DNA in breast fibroblasts. Epidermal growth factor (EGF) and insulin-like growth factor 1 both stimulated DNA synthesis in breast fibroblasts. Bradykinin inhibited this mitogenic effect of EGF but not that due to insulin-like growth factor 1. The binding of 125I-labeled EGF to fibroblasts was also inhibited by BK. Prostaglandin E2 also inhibited fibroblast DNA synthesis, and the cyclooxygenase inhibitor indomethacin partially reversed the inhibitory action of BK on DNA synthesis. Studies with BK receptor antagonists and agonists indicate that inositol lipid signalling and arachidonic acid mobilization in response to BK are B2 receptor-mediated pathways, whereas the inhibition of DNA synthesis appears to be via B1 receptors. Although these data support a role for prostaglandins and EGF receptor down-modulation in the inhibitory action of BK on DNA synthesis in breast fibroblasts, a B1 receptor-mediated pathway is also implicated. This study highlights a potential pathophysiological role for BK as a negative regulator of breast stromal cell growth.
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PMID:Inhibition of DNA synthesis and growth in human breast stromal cells by bradykinin: evidence for independent roles of B1 and B2 receptors in the respective control of cell growth and phospholipid hydrolysis. 130 39

The aim of this study was to assess the effect of cell culture on the bradykinin receptor of rabbit colon myocytes. In longitudinal muscle strips prepared from distal colon, bradykinin stimulated dose-dependent contraction that was 62% of the maximal response to bethanecol. At 4 degrees C, [3H]bradykinin binding to fresh muscle homogenates from the distal colon was time dependent, saturable, and linearly related to tissue concentration. Specific binding of 0.6 nmol/L [3H]bradykinin was 80% +/- 2% of total binding. In competitive binding studies, Hill coefficients approached unity, suggesting the presence of a single class of receptors. The order of potency was bradykinin greater than [D-Phe7]bradykinin much greater than des-Arg9, [Leu8]bradykinin, which is consistent with results of a B2 receptor subclass. Colon myocytes from the longitudinal muscle layer achieved confluence and were harvested for studies after 12-14 days in culture. Bradykinin receptors were of high affinity [disassociation constant (Kd) = 672 pmol/L] and numbered 10,217 +/- 2567/cell. To show that the receptors on cultured myocytes were functional, the effect of bradykinin was measured (a) on intracellular calcium concentration using Fura 2 and (b) on prostaglandin E2 concentration in the culture media using radioimmunoassay. In cells grown to confluence on cover slips and preloaded with Fura 2, bradykinin stimulated the threshold response at 1 nmol/L and maximal response (increased intracellular calcium concentration from 229 to 633 nmol/L) at 1 mumol/L. Bradykinin, 100 nmol/L, increased Prostaglandin E2 in the culture media threefold. In summary, colon myocytes express functioning bradykinin receptors, which, unlike muscarinic receptors, persist in culture. Bradykinin appears to be a suitable agonist for studies of receptor-mediated intracellular events in cultured colon myocytes.
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PMID:Effect of cell culture on rabbit colonic smooth muscle bradykinin receptors. 131 50

Receptor type and function of bradykinin (BK) receptors on human synovial fibroblasts (HSF) was determined. Scatchard analysis of [3H]BK saturation binding to intact synovial cells revealed a single binding site, with a Kd of 3.8 +/- 0.6 nM. HSF express approximately 50,000 BK sites/cell. Specificity of [3H]BK binding was confirmed by the ability of several BK peptide agonists and antagonists to inhibit binding in a dose dependent manner. The rank order of potency for agonist inhibition of [3H]BK and the inability of selective antagonists of the B1-type to displace binding suggest that the BK receptor on HSF is a B2 subtype receptor. The addition of BK to HSF caused a time and concentration dependent increase in PGE2 production. This BK induced PGE2 production was blocked by specific B2 type BK antagonists and not by B1 antagonists. The results of this study identify B2 type BK receptors on synovial fibroblasts and suggest that BK may be a primary mediator in inflammatory arthritis.
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PMID:Role of bradykinin in inflammatory arthritis: identification and functional analysis of bradykinin receptors on human synovial fibroblasts. 131 90

IMR90 human fetal lung fibroblasts express bradykinin receptors activating the pathway for biosynthesis of PGE2. A receptor of the B2 subtype stimulates half-maximal PGE2 production at 4.8 nM bradykinin, and maximal output takes place at 25 nM bradykinin. Radioligand binding studies reveal a population of [3H]bradykinin binding sites whose affinity correlates with this B2 receptor's biologic activity, with a KD of 2.5 nM. As IMR90 cells reach 60% of their defined life span in culture, they spontaneously induce expression of a second site of lower affinity, with half-maximal binding of [3H]bradykinin at 44 nM. This second site displays a characteristic primary B2 receptor recognition profile, but differs from the 2.5 nM site on a secondary level in recognition among different B2 ligands. Bradykinin is the most potent ligand at both sites; they each preferentially recognize an N-terminal extended bradykinin peptide construct having selectivity for the rat myometrial B2 receptor, suggesting that both sites have structural features in common. However, they display diversity in their order of preference for Met-Lys-bradykinin versus Lys-Lys-bradykinin; at the 44 nM site this order is completely reversed from the order of potency exhibited at the 2.5 nM site. Expression of the second site changes the manner in which these fibroblasts control their PGE2 production; it affords a graded response of PGE2 production at bradykinin levels beyond those which would normally saturate the 2.5 nM site. The inducibility of the 44 nM site in cultured fibroblasts addresses in vivo conditions in an inflammatory environment where continuing generation of bradykinin-related peptides takes place and presents a possible mechanism for overriding constraints that would otherwise limit the progression of inflammation.
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PMID:Diversity of B2 bradykinin receptors with nanomolar affinity expressed in passaged IMR90 human lung fibroblasts. 132 19

The purpose of this study was to gain insight into the mechanism(s) responsible for the exaggerated angiotensin II (ANG II)-induced renal vasoconstriction during the development of hypertension. In previous studies we observed that ANG II produces a twofold larger decrease in renal blood flow (RBF) in spontaneously hypertensive (SHR) compared with Wistar-Kyoto (WKY) rats before but not after cyclooxygenase inhibition. We suggested that this strain difference could be attributed to differences in renal prostaglandin (PG) levels and/or action. To evaluate these possibilities, measurements of RBF were made in 6-wk-old, anesthetized SHR and WKY pretreated with indomethacin. ANG II was injected intrarenally before and during continuous intrarenal infusion of a low dose of PGE2, viprostol (PGE2 analogue), PGI2, iloprost (PGI2 analogue), and bradykinin. In the control period ANG II reduced RBF by 50% in both strains. Infusion of PGs reduced the vasoconstrictor effect of ANG II in WKY, but had no effect in SHR. In contrast, infusion of bradykinin blunted the ANG II-induced vasoconstriction to a similar degree in both WKY and SHR. To investigate whether this lack of protection in SHR is due to strain differences in the number and/or affinity of renal receptors of PGs, radiolabeled ligand binding studies for PGE2 and PGI2 receptors were undertaken in glomeruli isolated from young WKY and SHR. Scatchard analysis revealed a single, high-affinity receptor site for PGE2 that was similar in both strains of rats. Both strains also exhibited a single, high-affinity PGI2 receptor site. No differences were observed in the PGE2 or PGI2 receptor number between WKY and SHR.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Impaired ability of prostaglandins to buffer renal vasoconstriction in genetically hypertensive rats. 132 56

The aim of the study was to determine the effect of bradykinin (BK) on the level of cytoplasmic-free Ca2+, [Ca2+]i, in human gingival fibroblasts and its relation to BK-induced prostanoid formation. BK, but not des-Arg9-BK, induced a significant rapid (within seconds) and transient increase in [Ca2+]i, that was not dependent on extracellular Ca2+. The stimulatory effect of BK was seen in concentrations at or above 10(-8) M, with the most pronounced effect at 10(-6) M. D-Arg0-Hyp3-Thi5,8-DPhe7-BK, a BK B2 receptor antagonist, but not des-Arg9-Leu8-BK, a BK B1 receptor antagonist, blocked BK-induced rise in [Ca2+]i. The BK B2 receptor antagonist also significantly reduced BK-induced PGE2 formation. When extracellular Ca2+ in the incubation medium was depleted, either by addition of EGTA or by omission of Ca2+ addition, BK still caused a significant stimulation of PGE2 formation. The calcium ionophores A23187 and ionomycin, similar to BK, caused a burst of PGE2 formation. The two phorbol esters phorbol 12,13-dibutyrate and 4-beta-phorbol-didecanoate positively amplified calcium ionophore A23187-induced PGE2 formation. The results indicate that BK-induced PGE2 formation in gingival fibroblasts is coupled to an increase in [Ca2+]i mediated by the BK B2 receptor, and which is independent of extracellular Ca2+.
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PMID:Bradykinin induces a B2 receptor-mediated calcium signal linked to prostanoid formation in human gingival fibroblasts in vitro. 133 26


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