Bradykinin stimulates airway epithelial Cl- secretion via two second messenger pathways

1990 ◽  
Vol 258 (6) ◽  
pp. L369-L377 ◽  
Author(s):  
J. J. Smith ◽  
J. D. McCann ◽  
M. J. Welsh

In canine airway epithelial cells, bradykinin increases intracellular concentrations of D-myo-inositol 1,4,5-trisphosphate [Ins(1,4,5)P3], cytosolic calcium concentration ([Ca2+]c), and adenosine 3',5'-cyclic monophosphate (cAMP). To determine the role of these second messengers in bradykinin-stimulated Cl- secretion, we studied the secretory response to this peptide using canine tracheal monolayers mounted in Ussing chambers. Bradykinin stimulated Cl- secretion [measured as short-circuit current (Isc)] when added to submucosal or mucosal surfaces; however, secretory responses differed substantially. Submucosal addition of bradykinin induced a biphasic increase in secretion; mucosal addition induced a monophasic increase in secretion. Both responses were mediated by B2 receptors. We show that activation of bradykinin receptors can stimulate Cl- secretion in two ways. 1) Bradykinin added to either surface stimulates prostaglandin synthesis and release at the basolateral surface. This leads to activation of prostaglandin E2-sensitive receptors on the basolateral surface that are coupled to cAMP production and an increase in apical membrane Cl- conductance. 2) In addition, bradykinin added to the submucosal surface increases Ins(1,4,5)P3 and [Ca2+]c levels, which enhance basolateral K+ conductance and the electrical driving force for apical Cl- exit. Whereas secretion requires activation of apical Cl- channels, the data show that Cl- secretion can also be modulated by activation of basolateral K+ channels. These data indicate that bradykinin-induced transepithelial Cl- secretion is mediated by two independent, second messenger pathways. These results provide the first evidence for expression of both pathways in a polar fashion in an epithelial monolayer.

1986 ◽  
Vol 251 (4) ◽  
pp. R818-R822 ◽  
Author(s):  
J. H. Widdicombe

Confluent cell sheets were cultured from the tracheal epithelium of normal humans or from tracheal and nasal epithelia of patients with cystic fibrosis (CF). Changes in short-circuit current (Isc) or cyclic AMP (cAMP) levels in response to 10(-5) M isoproterenol were measured. In CF tracheal cells the response to isoproterenol was transient, and the maximal increase in Isc was one-tenth normal. In CF nasal cells, isoproterenol or epinephrine caused only small transient increases in Isc. However, in both CF nasal and tracheal cells, the Ca ionophore, A23187, caused relatively large increases in Isc that were inhibited by the Cl transport blocker, bumetanide, suggesting that Cl secretion can be induced by raising intracellular levels of Ca. In normal tracheal cell sheets, cAMP levels increased within 15 s of isoproterenol addition and continued to increase for up to 20 min. Resting levels of cAMP in CF tracheal cells were not statistically different from those of normal cells and showed linear increases for up to 4 min after addition of isoproterenol. Changes in cAMP in CF nasal cells were similar to the changes in CF tracheal cells. After 2 min, all three cell types showed cAMP levels elevated approximately equal to 10-fold. These results suggest that receptor-activated stimulation of adenylate cyclase is normal in CF. However, though raised cAMP levels stimulate Cl secretion in normal, they are unable to do so in CF airway epithelial cells.


1994 ◽  
Vol 266 (5) ◽  
pp. L493-L501 ◽  
Author(s):  
B. Q. Shen ◽  
W. E. Finkbeiner ◽  
J. J. Wine ◽  
R. J. Mrsny ◽  
J. H. Widdicombe

Of 12 cell lines derived from human lung cancers, only Calu-3 cells showed high transepithelial resistance (Rte) and increases in short-circuit current (Isc) in response to mediators. Calu-3 cells formed polarized monolayers with tight junctions and Rte of approximately 100 omega.cm2. Baseline Isc was approximately 35 microA/cm2 and was increased by approximately 75 microA/cm2 on elevation of intracellular adenosine 3',5'-cyclic monophosphate (cAMP) by isoproterenol. Flux studies showed that the increase in Isc was due to Cl- secretion. Forskolin and permeant analogues of cAMP also increased Isc. Consistent with the presence of cAMP-dependent Cl- secretion, immunoprecipitation demonstrated the presence of the cystic fibrosis transmembrane conductance regulator (CFTR). Bradykinin, methacholine, trypsin, and histamine all transiently (15–30 s) elevated Isc, probably by increasing intracellular Ca concentration. Experiments in which the basolateral membrane was permeabilized with nystatin indicated that CFTR was substantially activated under baseline conditions and that Ca-activated Cl- channels were absent from the apical membrane. We anticipate that Calu-3 cells will prove useful in the study of Cl- secretion and other functions of human airway epithelial cells.


1991 ◽  
Vol 261 (2) ◽  
pp. L188-L194 ◽  
Author(s):  
P. I. Plews ◽  
Z. A. Abdel-Malek ◽  
C. A. Doupnik ◽  
G. D. Leikauf

The endothelins (ET) are a group of isopeptides produced by a number of cells, including canine tracheal epithelial cells. Because these compounds are endogenous peptides that may activate eicosanoid metabolism, we investigated the effects of ET on Cl secretion in canine tracheal epithelium. Endothelin 1 (ET-1) was found to produce a dose-dependent change in short-circuit current (Isc) that increased slowly and reached a maximal value within 10-15 min. When isopeptides of ET were compared, 300 nM ET-1 and ET-2 produced comparable maximal increases in Isc, whereas ET-3 produced smaller changes in Isc (half-maximal concentrations of 2.2, 7.2, and 10.4 nM, respectively). Ionic substitution of Cl with nontransported anions, iodide and gluconate, reduced ET-1-induced changes in Isc. Furthermore, the response was inhibited by the NaCl cotransport inhibitor, furosemide. In paired tissues, ET-1 significantly increased mucosal net 36Cl flux without significant effect on 22Na flux. The increase in Isc induced by ET was diminished by pretreatment with indomethacin. The second messengers mediating the increase in Isc were investigated in cultured canine tracheal epithelial cells. ET-1 stimulated the release of [3H]arachidonate from membrane phospholipids, increased intracellular Ca2+ (occasionally producing oscillations), and increased adenosine 3',5'-cyclic monophosphate accumulation. The latter was diminished by indomethacin. Thus ET is a potent agonist of Cl secretion (with the isopeptides having the following potency: ET-1 greater than or equal to ET-2 greater than ET-3) and acts, in part, through a cyclooxygenase-dependent mechanism.


1990 ◽  
Vol 259 (6) ◽  
pp. L459-L467 ◽  
Author(s):  
G. J. Tessier ◽  
T. R. Traynor ◽  
M. S. Kannan ◽  
S. M. O3'Grady

Equine tracheal epithelium, stripped of serosal muscle, mounted in Ussing chambers, and bathed in plasmalike Ringer solution generates a serosa-positive transepithelial potential of 10–22 mV and a short-circuit current (Isc) of 70–200 microA/cm2. Mucosal amiloride (10 microM) causes a 40–60% decrease in Isc and inhibits the net transepithelial Na flux by 95%. Substitution of Cl with gluconate resulted in a 30% decrease in basal Isc. Bicarbonate substitution with 20 mM N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid decreased the Isc by 21%. The Cl-dependent Isc was inhibited by serosal addition of 1 mM amiloride. Bicarbonate replacement or serosal amiloride (1 mM) inhibits the net Cl flux by 72 and 69%, respectively. Bicarbonate replacement significantly reduces the effects of serosal amiloride (1 mM) on Isc, indicating its effect is HCO3 dependent. Addition of 8-bromoadenosine 3',5'-cyclic monophosphate (8-BrcAMP; 100 microM) causes a 40% increase in Isc. This effect is inhibited by subsequent addition of 10 microM serosal bumetanide. Bumetanide (10 microM) reduces net Cl secretion following stimulation with 8-BrcAMP (100 microM). Serosal addition of BaCl2 (1 mM) causes a reduction in Isc equal to that following Cl replacement in the presence or absence of 100 microM cAMP. These results suggest that 1) Na absorption depends on amiloride-inhibitable Na channels in the apical membrane, 2) Cl influx across the basolateral membrane occurs by both a Na-H/Cl-HCO3 parallel exchange mechanism under basal conditions and by a bumetanide-sensitive Na-(K?)-Cl cotransport system under cAMP-stimulated conditions, and 3) basal and cAMP-stimulated Cl secretion depends on Ba-sensitive K channels in the basolateral membrane.


1991 ◽  
Vol 261 (6) ◽  
pp. L456-L461 ◽  
Author(s):  
G. J. Tessier ◽  
T. R. Traynor ◽  
M. S. Kannan ◽  
S. M. O'Grady

When the equine tracheal epithelium is mounted in Ussing chambers and bathed in plasma-like Ringer solution, the tissue generates a lumen-negative transepithelial potential (PD) of 22 mV and a short-circuit current (Isc) of 70-200 microA/cm2. Mucosal addition of 10 microM histamine produces a transient increase in the Isc followed by a return to baseline or below. Mucosal addition of 2 microM diphenhydramine inhibits the Isc response to mucosal histamine, whereas 100 microM mucosal cimetidine produces no effect. The average initial increases in Isc over time for mucosal vs. serosal histamine addition are significantly different (17.32 +/- 2.8 and 3.76 +/- 0.69 microA/min, respectively). Pretreatment with mucosal amiloride significantly prolongs the effect of mucosal histamine on Isc over a 20-min period from 4.73 +/- 0.33 to 15.48 +/- 3.16 microA. When Cl is replaced by gluconate, mucosal histamine addition results in a gradual decrease in Isc and significantly reduces the effect of mucosal amiloride on Isc from 80.8% to 54.9%. Mucosal histamine inhibits the net transepithelial Na flux by 42% and stimulates the secretion of Cl by 106%. Subsequent addition of serosal bumetanide decreases net Cl secretion by 70% These results suggest that histamine stimulates bumetanide-sensitive Cl secretion and inhibits amiloride-sensitive Na absorption; these effects are mediated by H1 receptors at the apical membrane surface


1999 ◽  
Vol 276 (1) ◽  
pp. G28-G36 ◽  
Author(s):  
Anthony T. Blikslager ◽  
Malcolm C. Roberts ◽  
Robert A. Argenzio

We have previously shown that PGI2 and PGE2 have a synergistic role in restoring electrical transepithelial resistance ( R) in ischemia-injured porcine ileum via the second messengers Ca2+ and cAMP. Because Ca2+ and cAMP stimulate Cl− secretion, we assessed the role of PG-induced Cl−secretion in recovery of R. Mucosa from porcine ileum subjected to ischemia for 45 min was mounted in Ussing chambers and bathed in indomethacin and Ringer solution. Addition of PGs stimulated a twofold increase in R, which was preceded by elevations in short-circuit current (increase of 25 μA/cm2). The PG-induced effect on R was partially inhibited with bumetanide, an inhibitor of Cl− secretion. The remaining elevations in R were similar in magnitude to those induced in ischemic tissues by amiloride, an inhibitor of Na+ absorption. Treatment with 10−4 M 8-bromo-cGMP or 300 mosM mucosal urea resulted in elevations in R similar to those attained with PG treatment. PGs signal recovery of Rvia induction of Cl−secretion and inhibition of Na+absorption, possibly by establishing a transmucosal osmotic gradient.


1986 ◽  
Vol 61 (3) ◽  
pp. 1065-1070 ◽  
Author(s):  
R. J. Corrales ◽  
D. L. Coleman ◽  
D. B. Jacoby ◽  
G. D. Leikauf ◽  
H. L. Hahn ◽  
...  

Sheets of trachea from ferret and cat were mounted in Ussing chambers and continuously short circuited. Under resting conditions, in both the cat and ferret there was little or no Cl secretion, and Na absorption accounted for most of the short-circuit current (Isc). Ouabain (10(-4) M, serosal bath) reduced Isc to zero in 30–60 min. This decline was matched by a decrease in net Na absorption. Amiloride (10(-4) M, luminal bath) caused a significant decrease in Isc and conductance (G) in both species. Bumetanide (10(-4) M, serosal bath) had negligible effects on Isc and G. In both species, isoproterenol increased Isc by stimulating Cl secretion. Methacholine induced equal amounts of Na and Cl secretion, with little change in Isc. In the cat, prostaglandins E2 and F2 alpha and bradykinin increased Isc, responses which were abolished in Cl-free medium. In open-circuited cat tissues, Na flux from the serosal to mucosal side was measured simultaneously with the secretion of nondialyzable 35S. Prostaglandins E1, E2, and F2 alpha, histamine, bradykinin, methacholine and isoproterenol all increased both Na and 35S-mucin secretion.


1995 ◽  
Vol 269 (2) ◽  
pp. R426-R431 ◽  
Author(s):  
T. R. Traynor ◽  
D. R. Brown ◽  
S. M. O'Grady

Electrical transmural stimulation (ETS) was used to examine the neuroregulation of electrolyte transport in the porcine distal colon. ETS of the colonic mucosa-submucosa mounted in Ussing chambers produced rapid and transient increases in short-circuit current (Isc) that were inhibited 36% by serosal bumetanide, suggesting that a portion of the response may be attributed to Cl secretion. ETS actions were dependent upon stimulus intensity and frequency and were inhibited by tetrodotoxin and omega-conotoxin. Prazosin and pyrilamine had no effect on the mucosal responses to ETS, whereas atropine reduced the responses by 32%. Neuropeptide Y (NPY) also reduced the mucosal responses to ETS up to 60% (half-maximal effective concentration = 17 nM). In addition, the effects of leukotriene C4, previously shown to stimulate Cl secretion via a neuronal pathway, were also inhibited by NPY. These results indicate that cholinergic submucosal neurons play a role in the regulation of epithelial ion transport and that NPY acts as an inhibitory neuromodulator, particularly on leukotriene-sensitive neurons in the porcine distal colon.


1991 ◽  
Vol 260 (4) ◽  
pp. C750-C755 ◽  
Author(s):  
T. R. Traynor ◽  
S. M. O'Grady

Porcine distal colon epithelium was mounted in Ussing chambers and bathed with porcine Ringer solution. The serosal addition of brain natriuretic peptide (BNP; 50 nM) or atriopeptin III (AP-III; 500 nM) produced significant increases (50-75 microA/cm2) in short-circuit current (Isc). These increases in Isc were not inhibited by pretreatment with tetrodotoxin (TTX) or 5,8,11,14-eicosatetraynoic acid (ETYA). Analysis of concentration-response relationships revealed that BNP was 5.8-fold more potent than AP-III in stimulating the Isc. BNP and AP-III significantly increased the serosal-to-mucosal (S----M) Cl flux and reduced net Cl absorption by 38 and 41%, respectively. The BNP-stimulated S----M Cl flux was abolished when HCO3 was removed. In contrast, the vasoactive intestinal peptide (VIP)-stimulated S----M Cl flux was not affected by HCO3 replacement. In addition to their effects on Cl transport, BNP and AP-III increased net Rb secretion by 79 and 58%, respectively. BNP-stimulated Rb secretion was reduced by 76% after HCO3 replacement. These results indicate that natriuretic peptides stimulate K- and HCO3-dependent Cl secretion which is not present under basal conditions or after VIP stimulation. The difference in potency between BNP and AP-III suggests that ANP-B receptors may mediate their effects on ion transport in the porcine colon.


1990 ◽  
Vol 259 (1) ◽  
pp. G62-G69 ◽  
Author(s):  
L. L. Clarke ◽  
R. A. Argenzio

In contrast to in vivo findings, the equine proximal colon fails to demonstrate significant net absorption of Na+ and Cl- under in vitro conditions. The present study was undertaken to determine if endogenous prostanoids are responsible for this apparent lack of ion transport. Proximal colonic tissues from ponies were preincubated in either normal Ringer solution or in Ringer containing 1 microM indomethacin and studied in Ussing chambers containing these solutions. Untreated colonic mucosa demonstrated negligible Na(+)-Cl- absorption in the basal state. In contrast, indomethacin-treated colon significantly absorbed Na+ and Cl-, primarily as the result of an equivalent increase in the mucosal-to-serosal flux of these ions. Preincubation of proximal colon in 0.1 mM ibuprofen-treated Ringer yielded similar results. Treatment of indomethacin colon with 1 mM mucosal amiloride eliminated net Na(+)-Cl- absorption without affecting the short-circuit current (Isc). The Isc in control tissue was significantly greater than in indomethacin-treated tissue and was reduced by 0.1 mM serosal furosemide. Serosal addition of 0.1 microM prostaglandin E2 or 10 mM serosal plus mucosal theophylline to indomethacin-treated tissues abolished net Na(+)-Cl- absorption and increased the Isc to levels indistinguishable from control. In contrast, control tissues were essentially unaffected by these secretagogues. These findings indicated that Na(+)-Cl- absorption in equine proximal colon was electroneutral (possibly involving Na(+)-H+ exchange) and that the tissue was capable of electrogenic Cl- secretion. However, under the in vitro conditions, basal ion transport was dominated by endogenous prostanoids that abolished Na(+)-Cl- absorption and elicited near-maximal electrogenic Cl- secretion.


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