Nitric oxide donors reduce the rise in reperfusion-induced intestinal mucosal permeability

1993 ◽  
Vol 265 (1) ◽  
pp. G189-G195 ◽  
Author(s):  
D. Payne ◽  
P. Kubes

Recent data have demonstrated that inhibition of nitric oxide synthesis exacerbated the mucosal injury associated with reperfusion of the postischemic intestine. In this study, using a feline 1-h intestinal ischemia followed by reperfusion model, we tested the possibility that exogenous sources of nitric oxide may prevent the reperfusion-induced mucosal barrier disruption and examined the mechanisms involved. Mucosal barrier integrity was assessed by determining 51Cr-EDTA clearance from blood to lumen. Intestinal blood flow and resistance were also determined. Reperfusion after 1 h of ischemia significantly increased 51Cr-EDTA clearance (0.05 +/- 0.01 to 0.35 +/- 0.07 ml.min-1.100 g-1) and decreased intestinal blood flow by 50%. Exogenous sources of nitric oxide including SIN-1, CAS-754, and nitroprusside as well as exogenous L-arginine all reduced reperfusion-induced mucosal barrier dysfunction without improving intestinal blood flow. Inhibition of endogenous nitric oxide with NG-nitro-L-arginine methyl ester between 1 and 2 h of reperfusion further augmented the rise in mucosal permeability associated with ischemia-reperfusion. Addition of the permeable analogue of guanosine 3',5'-cyclic monophosphate, 8-bromoguanosine 3',5'-cyclic monophosphate, improved reperfusion-induced intestinal blood flow significantly but did not provide protection against mucosal barrier disruption associated with the first hour of ischemia-reperfusion. Exogenous sources of nitric oxide can reduce reperfusion-induced mucosal barrier dysfunction independent of alterations in intestinal blood flow.

1999 ◽  
Vol 277 (2) ◽  
pp. H676-H682 ◽  
Author(s):  
Paul Kubes ◽  
Derrice Payne ◽  
Matthew B. Grisham ◽  
David Jourd-Heuil ◽  
Alison Fox-Robichaud

Inhaled nitric oxide (NO) reduces pulmonary hypertension and dampens various aspects of lung inflammation; however, its effects are thought to be restricted to the lung because of its short half-life in biological systems. More recently, however, NO was shown to nitrosylate hemoglobin, albumin, and other plasma molecules to form stable nitrosothiol derivatives and could have an impact on the periphery. We examined whether inhaled NO could have an impact on the two compartments of distal organs, namely, the intravascular and extravascular spaces. The feline intestine was exposed to 1 h of ischemia and 1 h of reperfusion, and intestinal blood flow and mucosal dysfunction were measured in animals ventilated with room air and inhaling 0 or 80 ppm NO. A decrease in intestinal blood flow and an increase in mucosal barrier leakiness were noted in animals not exposed to inhaled NO. The intestinal blood flow impairment was entirely reversed in animals breathing 80 ppm NO, but the mucosal dysfunction was not affected. We further examined whether inhaled NO could reach the extravascular space by simply inhibiting NO in the intestine with the NO synthase inhibitor N G-nitro-l-arginine methyl ester (l-NAME) that causes an increase in mucosal permeability that is rapidly reversed with NO donors. However, inhaled NO had no effect on the rise in mucosal permeability. l-NAME reduced lymph nitrosothiol concentrations, but inhaled NO could not replenish these levels. To further explore the intravascular impact of inhaled NO, we used intravital microscopy to visualize the microvasculature and demonstrated that inhaled NO could be initiated after reperfusion and still reduced microvascular disturbances, including reversing the impairment in blood flow and increasing leukocyte adhesion. The effects of inhaled NO persisted for an additional hour after termination of NO inhalation, consistent with a dramatic increase in nitrate within 1 h of NO inhalation, which persisted for 1 h after the termination of NO inhalation. These data suggest that inhaled NO can reach distal organs to dramatically improve reperfusion-induced microvascular but not extravascular dysfunction.


1993 ◽  
Vol 264 (1) ◽  
pp. G143-G149 ◽  
Author(s):  
P. Kubes

The objective of this study was to assess whether nitric oxide synthesis inhibition affects intestinal barrier function after ischemia-reperfusion of the feline small bowel. Local intra-arterial infusion of the nitric oxide synthesis inhibitor NG-nitro-L-arginine methyl ester (L-NAME; 25 nmol.ml-1.min-1) was performed in autoperfused segments of cat ileum for 60 min after 90 min of ischemia and 60 min of reperfusion. Epithelial permeability was quantitated by measuring blood-to-lumen clearance of 51Cr-labeled EDTA, and microvascular dysfunction was assessed by measuring the clearance of protein from the vasculature into the interstitium. 125I-labeled albumin clearance from blood to lumen and histology were performed to further characterize the extent of intestinal dysfunction after reperfusion of the postischemic intestine in the presence and absence of L-NAME. Ischemia-reperfusion-induced mucosal and microvascular permeability increases were dramatically augmented by L-NAME infusion, and this effect was reversed by infusion of L-arginine (125 nmol.ml-1.min-1). Initiating L-arginine (but not D-arginine) infusion alone 10 min before reperfusion provided protection against ischemia-reperfusion-induced mucosal barrier dysfunction; however, this was not associated with a reduction in endogenous levels of L-arginine during ischemia-reperfusion. These data suggest that basal nitric oxide production is important in minimizing mucosal and microvascular barrier dysfunction associated with reperfusion of postischemic intestine.


1995 ◽  
Vol 269 (1) ◽  
pp. G34-G41 ◽  
Author(s):  
P. Kubes ◽  
P. H. Reinhardt ◽  
D. Payne ◽  
R. C. Woodman

The overproduction of nitric oxide in the small bowel has been invoked as a cytotoxic event in the vascular, mucosal, and whole organ dysfunction associated with inflammation. We assessed whether exogenous administration of nitric oxide in the form of nitric oxide donors (CAS 754, SIN-1) could cause microvascular and mucosal barrier dysfunction in vivo or epithelial and endothelial cell permeability alterations and cell injury in vitro. Increasing concentrations of CAS 754 or SIN-1 were infused locally into autoperfused segments of cat ileum at 30-min intervals. Baseline epithelial permeability (blood-to-lumen clearance of 51Cr-EDTA) was not affected by CAS 754, whereas vascular protein clearance was reduced. The latter effect could almost entirely be explained by a decrease in intestinal capillary hydrostatic pressure. Therefore, in some experiments venous pressure was elevated and the microvascular reflection coefficient for total proteins was estimated at filtration-independent rates. This direct measurement of microvascular permeability was unaffected by exogenous nitric oxide. CAS 754 did not increase permeability across monolayers of endothelial or epithelial cells and did not cause cell injury. Next, we assessed the possibility that excess nitric oxide may be detrimental, but only in inflamed intestine, by infusing CAS 754 with platelet-activating factor; the latter directly increases microvascular and mucosal permeability. CAS 754 did not exacerbate but rather reduced platelet-activating factor-induced rise in microvascular and mucosal permeability. These results suggest that high concentrations of nitric oxide do not cause breakdown of mucosal or microvascular barrier integrity under normal or inflammatory conditions.


2017 ◽  
Vol 313 (5) ◽  
pp. H988-H999 ◽  
Author(s):  
Hongyan Dai ◽  
Meifang Wang ◽  
Parag N. Patel ◽  
Theodore Kalogeris ◽  
Yajun Liu ◽  
...  

Activation of large-conductance Ca2+-activated K+ (BKCa) channels evokes cell survival programs that mitigate intestinal ischemia and reperfusion (I/R) inflammation and injury 24 h later. The goal of the present study was to determine the roles of reactive oxygen species (ROS) and heme oxygenase (HO)-1 in delayed acquisition of tolerance to I/R induced by pretreatment with the BKCa channel opener NS-1619. Superior mesentery arteries were occluded for 45 min followed by reperfusion for 70 min in wild-type (WT) or HO-1-null (HO-1−/−) mice that were pretreated with NS-1619 or saline vehicle 24 h earlier. Intravital microscopy was used to quantify the numbers of rolling and adherent leukocytes. Mucosal permeability, tumor necrosis factor-α (TNF-α) levels, and HO-1 activity and expression in jejunum were also determined. I/R induced leukocyte rolling and adhesion, increased intestinal TNF-α levels, and enhanced mucosal permeability in WT mice, effects that were largely abolished by pretreatment with NS-1619. The anti-inflammatory and mucosal permeability-sparing effects of NS-1619 were prevented by coincident treatment with the HO-1 inhibitor tin protoporphyrin-IX or a cell-permeant SOD mimetic, Mn(III)tetrakis (4-benzoic acid) porphyrin (MnTBAP), in WT mice. NS-1619 also increased jejunal HO-1 activity in WT animals, an effect that was attenuated by treatment with the BKCa channel antagonist paxilline or MnTBAP. I/R also increased postischemic leukocyte rolling and adhesion and intestinal TNF-α levels in HO-1−/− mice to levels comparable to those noted in WT animals. However, NS-1619 was ineffective in preventing these effects in HO-1-deficient mice. In summary, our data indicate that NS-1619 induces the development of an anti-inflammatory phenotype and mitigates postischemic mucosal barrier disruption in the small intestine by a mechanism that may involve ROS-dependent HO-1 activity. NEW & NOTEWORTHY Antecedent treatment with the large-conductance Ca2+-activated K+ channel opener NS-1619 24 h before ischemia-reperfusion limits postischemic tissue injury by an oxidant-dependent mechanism. The present study shows that NS-1619-induced oxidant production prevents ischemia-reperfusion-induced inflammation and mucosal barrier disruption in the small intestine by provoking increases in heme oxygenase-1 activity.


2006 ◽  
Vol 175 (4S) ◽  
pp. 521-521
Author(s):  
Motoaki Saito ◽  
Tomoharu Kono ◽  
Yukako Kinoshita ◽  
Itaru Satoh ◽  
Keisuke Satoh

1993 ◽  
Vol 264 (2) ◽  
pp. G272-G279 ◽  
Author(s):  
O. Nylander ◽  
E. Wilander ◽  
G. M. Larson ◽  
L. Holm

The duodenum in anesthetized rats was perfused with HCl, and mucosal integrity was assessed by measuring the clearance of 51Cr-labeled EDTA from blood to lumen and/or by morphological examination (lesion score). Duodenal blood flow was determined by laser Doppler flowmetry and luminal alkalinization as well as H+ disappearance by backtitration. Intravenous infusion of vasoactive intestinal polypeptide (VIP; 13.5 micrograms.kg-1.h-1) increased luminal alkalinization threefold and decreased clearance of 51Cr-EDTA by 50%. VIP also decreased arterial blood pressure and induced a small and irregular decrease in duodenal blood flow. Perfusion with 10 mM HCl increased clearance of 51Cr-EDTA 2.1-fold, but the lesion score was not different from that in saline-perfused animals. Perfusion with 20 mM HCl increased clearance of 51Cr-EDTA four-fold and induced a greater lesion score than did 10 mM. Perfusion with either 10 or 20 mM HCl did not affect the duodenal blood flow. VIP reduced the rise in clearance of 51Cr-EDTA in response to 10 mM but not that to 20 mM HCl. Intravenous injection of prazosin (50 micrograms/kg) decreased luminal alkalinization, clearance of 51Cr-EDTA, blood pressure, and duodenal blood flow. In prazosin-pretreated rats, perfusion with 10 mM HCl increased clearance of 51Cr-EDTA 2.6-fold, and the lesion score was greater in this group than in animals infused with VIP. A positive linear correlation was obtained between HCO3- secretion and the mean rate of H+ disappearance.(ABSTRACT TRUNCATED AT 250 WORDS)


1993 ◽  
Vol 265 (6) ◽  
pp. H1909-H1915 ◽  
Author(s):  
P. Kubes

This study evaluated the physiological effects of compounds that alter guanosine 3',5'-cyclic monophosphate (cGMP) on the increase in vascular protein clearance induced by nitric oxide (NO) synthesis inhibition in the feline small intestine. A lymphatic vessel draining the small bowel was cannulated; vascular protein clearance and intestinal blood flow were measured. N omega-nitro-L-arginine methyl ester (L-NAME), the NO inhibitor, was infused (0.5 mumol/min) into the superior mesenteric artery. Vascular protein clearance increased approximately 4.6-fold, whereas blood flow decreased to 50% of control. Elevation of cGMP by 1) cytosolic guanylate cyclase activation with a NO donor (SIN 1) or 2) a cGMP analogue, 8-bromoguanosine 3',5'-cyclic monophosphate (8-BrcGMP) completely prevented the rise in microvascular permeability associated with L-NAME. Moreover, these compounds reduced (almost 90%) baseline vascular protein clearance, whereas inhibition of cytosolic guanylate cyclase with methylene blue significantly increased this parameter. Atrial natriuretic factor (ANF) has been reported to increase tissue cGMP levels and microvascular permeability. In this study, ANF did indeed increase intestinal microvascular permeability however this occurred independent of changes in intestinal cGMP levels. These data support a role for cGMP associated with NO-induced microvascular permeability alterations and raise the possibility that ANF has a cGMP-independent effect on microvascular permeability within the intestine.


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