scholarly journals Methotrexate potentiates bradykinin-induced increase in macromolecular efflux from the hamster oral mucosa

1997 ◽  
Vol 273 (4) ◽  
pp. R1254-R1262 ◽  
Author(s):  
Xiao-Pei Gao ◽  
Israel Rubinstein
Keyword(s):  
Nitric Oxide ◽  
Methyl Ester ◽  
Oral Mucosa ◽  
Biosynthetic Pathway ◽  
Fluorescein Isothiocyanate ◽  
Cheek Pouch ◽  
Site Formation ◽  
Induced Responses ◽  
Hamster Cheek Pouch

The purpose of this study was to determine whether methotrexate modulates bradykinin-induced increase in macromolecular efflux from the in situ oral mucosa and whether this response is mediated by thel-arginine/nitric oxide biosynthetic pathway. Using intravital microscopy, we found that suffusion of methotrexate alone onto the hamster cheek pouch had no significant effects on leaky site formation and increase in clearance of fluorescein isothiocyanate-labeled dextran (molecular mass, 70 kDa). However, methotrexate significantly potentiated bradykinin-induced responses ( P < 0.05). These effects were associated with significant increases in nitrites concentration and guanosine 3′,5′-cyclic monophosphate-like immunoreactivity in the suffusate and were abrogated by N G-nitro-l-arginine methyl ester (l-NAME) but not N G-nitro-d-arginine methyl ester (d-NAME).l-Arginine, but notd-arginine, abolishedl-NAME-induced responses. ZnCI2 and indomethacin had no significant effects on methotrexate-induced responses. Methotrexate had no significant effects on adenosine- and ionomycin-induced increases in macromolecular efflux. Collectively, these data indicate that methotrexate amplifies bradykinin-induced increase in macromolecular efflux from the in situ oral mucosa in a specific, receptor- andl-arginine/nitric oxide biosynthetic pathway-dependent fashion.

Loop diuretics attenuate bradykinin-induced increase in clearance of macromolecules in the oral mucosa

1996 ◽  
Vol 80 (3) ◽  
pp. 818-823 ◽  
Author(s):  
X. P. Gao ◽  
J. M. Conlon ◽  
J. K. Vishwanatha ◽  
R. A. Robbins ◽  
I. Rubinstein
Keyword(s):  
Oral Mucosa ◽  
Fluorescein Isothiocyanate ◽  
Loop Diuretics ◽  
Cheek Pouch ◽  
Site Formation ◽  
Induced Responses ◽  
Vasomotor Tone ◽  
Hamster Cheek Pouch ◽  
Significant Concentration

The purpose of this study was to determine whether loop diuretics attenuate bradykinin-induced increase in clearance of macromolecules in the oral mucosa in situ and, if so, to start to determine the mechanisms that mediated these responses. By using intravital microscopy, we found that bradykinin induced a significant concentration-dependent increase in fluorescein isothiocyanate-labeled dextran (mol mass 70 kDa) leaky site formation in the hamster cheek pouch. These responses were significantly attenuated by topical application of two structurally distinct loop diuretics, furosemide and ethacrynic acid, onto the cheek pouch (P < 0.05). Hydrochlorothiazide, a nonloop diuretic, had no significant effects on bradykinin-induced responses. Furosemide had no significant effects on adenosine-induced leaky site formation. Application of bradykinin after furosemide, but not after hydrochlorothiazide, was associated with a significant concentration-dependent decrease in bradykinin-like immunoreactivity in the cheek pouch suffusate (P < 0.05). Prostaglandins and changes in vasomotor tone did not modulate the effects of furosemide on bradykinin-induced responses. These data indicate that loop diuretics attenuate bradykinin-induced increase in clearance of macromolecules in the oral mucosa in a specific fashion, probably by amplifying local bradykinin catabolism. We suggest that topical loop diuretics could be useful in the treatment of oral mucosa inflammation elicited by bradykinin.

scholarly journals Subtilisin Increases Macromolecular Efflux from the Oral Mucosa

2000 ◽  
Vol 7 (5) ◽  
pp. 794-802 ◽  
Author(s):  
Israel Rubinstein
Keyword(s):  
Receptor Antagonist ◽  
Oral Mucosa ◽  
Serine Proteinase ◽  
Fluorescein Isothiocyanate ◽  
Cheek Pouch ◽  
Site Formation ◽  
Induced Responses ◽  
Hamster Cheek Pouch ◽  
Neurokinin 1

ABSTRACT The purpose of this study was to determine whether subtilisin, a potent serine proteinase derived from Bacillus species contaminating smokeless tobacco, increases macromolecular efflux from the oral mucosa and, if so, whether local elaboration of bradykinin mediates this response. Using intravital microscopy, I found that suffusion of subtilisin elicits significant, concentration-dependent leaky site formation and an increase in the clearance of fluorescein isothiocyanate-labeled dextran (molecular mass, 70 kDa) from the in situ hamster cheek pouch (P < 0.05). Heat-inactivated subtilisin had no significant effects on macromolecular efflux. Subtilisin-induced responses were significantly attenuated by Hoe 140 and NPC 17647, two structurally distinct selective bradykinin B2 receptor antagonists, but not by des-Arg9-[Leu8]bradykinin, a selective bradykinin B1 receptor antagonist, or CP-96,345, a selective neurokinin-1 receptor antagonist. Aprotinin, but not leupeptin, significantly attenuated subtilisin-induced increase in macromolecular efflux. Indomethacin had no significant effects on subtilisin-induced responses. Collectively, these data indicate that subtilisin increases the macromolecular efflux from the in situ hamster cheek pouch in a catalytic-site-dependent fashion through local elaboration of bradykinin. This response does not involve the stimulation of local afferent nerves or the production of prostaglandins.

Tannic acid elicits neurogenic plasma exudation from the in situ hamster cheek pouch

1998 ◽  
Vol 274 (1) ◽  
pp. R237-R242
Author(s):  
Xiao-Pei Gao
Keyword(s):  
Tannic Acid ◽  
Biosynthetic Pathway ◽  
Fluorescein Isothiocyanate ◽  
Cheek Pouch ◽  
Site Formation ◽  
Hamster Cheek Pouch ◽  
Plasma Exudation ◽  
Synthase Inhibitor

The purpose of this study was to determine whether tannic acid elicits neurogenic plasma exudation from the oral mucosa in vivo and, if so, whether this response is transduced in part by thel-arginine-nitric oxide (NO) biosynthetic pathway. Using intravital microscopy, we found that suffusion of tannic acid elicits significant concentration-dependent leaky site formation and increase in clearance of fluorescein isothiocyanate-dextran (molecular mass 70 kDa) from the in situ hamster cheek pouch ( P < 0.05). These effects are significantly attenuated by two selective, but structurally distinct, nonpeptide neurokinin-1 (NK1) receptor antagonists, CP-96,345 and RP-67580, but not by CP-96,344, the 2R,3R enantiomer of CP-96,345. N G-nitrol-arginine methyl ester (l-NAME), an NO synthase inhibitor, but notd-NAME, significantly attenuates tannic acid-induced responses.l-Arginine, but notd-arginine, reverses the attenuating effects of l-NAME. We conclude that tannic acid elicitsl-arginine-NO biosynthetic pathway-dependent neurogenic plasma exudation from the in situ hamster cheek pouch.

scholarly journals Dexamethasone attenuates acute macromolecular efflux increase evoked by smokeless tobacco extract

1999 ◽  
Vol 87 (2) ◽  
pp. 619-625 ◽  
Author(s):  
Xiao-Pei Gao ◽  
Syed R. Akhter ◽  
Hiroyuki Ikezaki ◽  
Dennis Hong ◽  
Israel Rubinstein
Keyword(s):  
Oral Mucosa ◽  
Smokeless Tobacco ◽  
Fluorescein Isothiocyanate ◽  
Cheek Pouch ◽  
Site Formation ◽  
Hamster Cheek Pouch ◽  
Acute Increase ◽  
Tobacco Extract

The purpose of this study was to determine whether dexamethasone attenuates the acute increase in macromolecular efflux from the oral mucosa elicited by an aqueous extract of smokeless tobacco (STE) in vivo, and, if so, whether this response is specific. Using intravital microscopy, we found that 20-min suffusion of STE elicited significant, concentration-related leaky site formation and an increase in clearance of fluorescein isothiocyanate-labeled dextran (FITC-dextran; mol mass 70 kDa) from the in situ hamster cheek pouch ( P < 0.05). This response was significantly attenuated by dexamethasone (10 mg/kg iv). Dexamethasone also attenuated the bradykinin-induced leaky site formation and the increase in clearance of FITC-dextran from the cheek pouch. However, it had no significant effects on adenosine-induced responses. Dexamethasone had no significant effects on baseline arteriolar diameter and on bradykinin-induced vasodilation in the cheek pouch. Collectively, these data indicate that dexamethasone attenuates, in a specific fashion, the acute increase in macromolecular efflux from the in situ oral mucosa evoked by short-term suffusion of STE. We suggest that corticosteroids mitigate acute oral mucosa inflammation elicited by smokeless tobacco.

Interleukin-1 beta potentiates bradykinin-induced macromolecular efflux from hamster oral mucosa

1997 ◽  
Vol 272 (1) ◽  
pp. R294-R301
Author(s):  
X. P. Gao ◽  
I. Rubinstein
Keyword(s):  
Receptor Antagonist ◽  
Oral Mucosa ◽  
Interleukin 1 ◽  
Fluorescein Isothiocyanate ◽  
Cheek Pouch ◽  
Site Formation ◽  
Interleukin 1 Beta ◽  
Vasomotor Tone ◽  
Hamster Cheek Pouch

The purpose of this study was to determine whether interleukin-1 beta (IL-1 beta) elicits macromolecular efflux from the in situ oral mucosa and whether it amplifies that evoked by bradykinin. Using intravital microscopy, we found that suffusion of recombinant human IL-1 beta (50 ng/ml) had no significant effects on leaky site formation and increase in clearance of fluorescein isothiocyanate-labeled dextran (mol mass 70 kDa) from the hamster cheek pouch. However, it significantly potentiated bradykinin-induced macromolecular efflux (P < 0.05). The potentiating effects of IL-1 beta on bradykinin-induced responses were abrogated by a bradykinin B2-receptor antagonist and by a recombinant human IL-1-receptor antagonist. They were not mediated by substance P, prostaglandins, or changes in vasomotor tone. IL-1 beta had no significant effects on adenosine-induced macromolecular efflux. Collectively, these data indicate that IL-1 beta potentiates bradykinin-induced macromolecular efflux from the in situ hamster oral mucosa in a specific fashion. We suggest that this interaction could play a role in the pathogenesis of oral mucosa inflammation.

Adenosine A1 receptors mediate plasma exudation from the oral mucosa

2001 ◽  
Vol 91 (2) ◽  
pp. 552-560 ◽  
Author(s):  
Israel Rubinstein ◽  
Rinku Chandilawa ◽  
Sumeet Dagar ◽  
Dennis Hong ◽  
Xiao-Pei Gao
Keyword(s):  
Nitric Oxide ◽  
Adenosine Receptor ◽  
Fluorescein Isothiocyanate ◽  
Cheek Pouch ◽  
Site Formation ◽  
Receptor Subtype ◽  
Induced Responses ◽  
Hamster Cheek Pouch ◽  
Nitric Oxide Synthase Inhibitor ◽  
Cgs 21680

The purpose of this study was to pharmacologically characterize the adenosine receptor subtype(s) that mediates adenosine-induced increases in macromolecular efflux from the intact hamster cheek pouch. Using intravital microscopy, we found that 1,3-dipropyl-8-(2-amino-4-chlorophenyl)-xanthine (PACPX), a selective adenosine receptor-1 antagonist, but not 3,7-dimethyl-1-propargylxanthine (DMPX), a selective adenosine receptor-2 antagonist, significantly attenuated adenosine-induced leaky site formation and increased clearance of fluorescein isothiocyanate-labeled dextran (molecular mass, 70 kDa) from the intact hamster cheek pouch ( P < 0.05). Both compounds had no significant effects on bradykinin-induced responses. Nanomolar concentrations of R(−)- N 6-(2-phenylisopropyl)-adenosine [R(−)-PIA], a selective adenosine A1 agonist, evoked significant, concentration-dependent increases in macromolecular efflux. This response was significantly attenuated by PACPX but not by DMPX. In contrast, CGS-21680, a selective adenosine A2agonist, increased macromolecular efflux but only at micromolar concentrations. This response was significantly attenuated by DMPX but not by PACPX. Suffusion of nitroglycerin had no significant effects on R(−)-PIA- and CGS-21680-induced responses. In addition, suffusion of N G-nitro-l-arginine methyl ester, a nitric oxide synthase inhibitor, had no significant effects on adenosine-induced responses. Indomethacin had no significant effects on adenosine-, R(−)-PIA-, and CGS-21680-induced increases in macromolecular efflux. Collectively, these data indicate that adenosine increases macromolecular efflux from the intact hamster cheek pouch by stimulating high-affinity adenosine A1 receptors in a specific, nitric oxide- and prostaglandin-independent fashion.

Stable VIP analogue Ro-24-9981 potentiates substance P-induced plasma exudation in hamster cheek pouch

1995 ◽  
Vol 79 (3) ◽  
pp. 968-974 ◽  
Author(s):  
X. P. Gao ◽  
H. A. Jaffe ◽  
C. O. Olopade ◽  
I. Rubinstein
Keyword(s):  
Methyl Ester ◽  
Substance P ◽  
Calcium Ionophore ◽  
Fluorescein Isothiocyanate ◽  
No Synthase ◽  
Cheek Pouch ◽  
Site Formation ◽  
Induced Responses ◽  
Hamster Cheek Pouch ◽  
Plasma Exudation

The purpose of this study was to determine whether vasoactive intestinal peptide (VIP; 300 nM) and a stable cyclic analogue of VIP, Ro-24–9981 (226 nM), modulated neurogenic plasma exudation in the oral cavity in situ and, if so, to determine the mechanisms that mediated these responses. With the use of intravital microscopy, we found that suffusion of substance P induced a significant concentration-dependent formation of fluorescein-isothiocyanate-dextran (mol wt 70 kDa) leaky sites in the hamster cheek pouch (P < 0.05). These effects were significantly and stereospecifically attenuated by NG-nitro-L-arginine methyl ester, an inhibitor of NO synthase, and restored by L-arginine, the substrate for NO synthase (P < 0.05). Topical application of human VIP and Ro-24–9981 had no significant effects of leaky site formation. In addition, human VIP had no significant effects on substance P-induced responses. By contrast, Ro-24–9981 significantly potentiated substance P- and capsaicin-induced leaky site formation (P < 0.05). The effects of Ro-24–9981 on substance P-induced responses were significantly attenuated by NG-nitro-L-arginine methyl ester and restored by L-arginine (P < 0.05). Indomethacin had no significant effects on Ro-24–9981-induced responses. Ro-24–9981 had no significant effects on adenosine- and calcium ionophore A-23187-induced leaky site formation. Collectively, these data suggest that VIP plays no significant role in modulating neurogenic plasma exudation in the oral mucosa. By contrast, Ro-24–9981 amplified this response in a specific receptor-mediated fashion.

The stable VIP analogue, Ro 24-9981, potentiates bradykinin-induced increases in clearance of macromolecules

1995 ◽  
Vol 269 (5) ◽  
pp. H1648-H1655
Author(s):  
X. P. Gao ◽  
I. Rubinstein
Keyword(s):  
Nitric Oxide ◽  
Methyl Ester ◽  
Oral Mucosa ◽  
Cyclic Peptide ◽  
Fluorescein Isothiocyanate ◽  
Cheek Pouch ◽  
Site Formation ◽  
Ionophore A23187 ◽  
Plasma Exudation ◽  
Fluorescein Isothiocyanate Dextran

The purpose of this study was to determine whether the stable cyclic peptide analogue of human vasoactive intestinal peptide, Ro 24-9981, modulates bradykinin-induced plasma exudation in the oral mucosa and if so, to determine the mechanisms that mediated these responses. Using intravital microscopy, we found that suffusion of Ro 24-9981 had no significant effects on leaky site formation and clearance of fluorescein-isothiocyanate-dextran (mol mass 70 kDa) in the hamster cheek pouch. However, Ro 24-9981 significantly potentiated bradykinin-induced increases in leaky site formation and clearance of fluorescein-isothiocyanate-dextran (P < 0.05). These effects were specific because Ro 24-9981 had no significant effects on adenosine and calcium ionophore A23187-induced increases in leaky site formation and clearance of fluorescein-isothiocyanate-dextran. Furthermore, they were not mediated by cyclooxygenase products of arachidonic acid metabolism because indomethacin was ineffective. NG-nitro-L-arginine methyl ester, a selective inhibitor of nitric oxide synthase, but not NG-nitro-D-arginine methyl ester, significantly attenuated the effects of both bradykinin and Ro 24-9981 with bradykinin (P < 0.05). These responses were restored by L-arginine but not D-arginine. Collectively, these data indicate that bradykinin-induced plasma exudation in the oral mucosa was potentiated by Ro 24-9981 in a specific receptor-mediated fashion. These responses were mediated, in part, by the L-arginine/nitric oxide biosynthetic pathway.

scholarly journals Purified ACE attenuates smokeless tobacco-induced increase in macromolecular efflux from the oral mucosa

1997 ◽  
Vol 83 (1) ◽  
pp. 74-81 ◽  
Author(s):  
Xiao-Pei Gao ◽  
Hideyuki Suzuki ◽  
Christopher O. Olopade ◽  
Sergei Pakhlevaniants ◽  
Israel Rubinstein
Keyword(s):  
Oral Mucosa ◽  
Smokeless Tobacco ◽  
Fluorescein Isothiocyanate ◽  
Cheek Pouch ◽  
Site Formation ◽  
Hamster Cheek Pouch ◽  
Rabbit Lung ◽  
Angiotensin I Converting Enzyme ◽  
Tobacco Extract

Gao, Xiao-pei, Hideyuki Suzuki, Christopher O. Olopade, Sergei Pakhlevaniants, and Israel Rubinstein. Purified ACE attenuates smokeless tobacco-induced increase in macromolecular efflux from the oral mucosa. J. Appl. Physiol. 83(1): 74–81, 1997.—The purpose of this study was to determine whether purified angiotensin I-converting enzyme (ACE) attenuates smokeless tobacco extract (STE)-induced increase in macromolecular efflux from the in situ oral mucosa. By using intravital microscopy, we found that suffusion of an aqueous extract of smokeless tobacco elicited significant concentration-dependent leaky site formation and increase in clearance of fluorescein isothiocyanate-labeled dextran (mol mass, 70 kDa) from the hamster cheek pouch ( P< 0.05). Suffusion of purified rabbit lung ACE significantly attenuated these responses in a concentration-dependent fashion ( P < 0.05). These effects were specific because purified ACE also significantly attenuated the increase in macromolecular efflux elicited by bradykinin, which is produced in the cheek pouch during suffusion of STE, but did not attenuate the increase elicted by adenosine. Moreover, suffusion of heat-inactivated purified ACE and purified superoxide dismutase had no significant effects on STE- and bradykinin-induced responses. Collectively, these data suggest that exogenous ACE attenuates STE-induced increase in macromolecular efflux from the in situ oral mucosa, in part, by promoting local bradykinin catabolism.

Ovalbumin increases macromolecular efflux from the in situ nasal mucosa of allergic hamsters

1998 ◽  
Vol 84 (1) ◽  
pp. 169-176 ◽  
Author(s):  
Xiao-Pei Gao ◽  
Syed R. Akhter ◽  
Israel Rubinstein
Keyword(s):  
Nitric Oxide ◽  
Methyl Ester ◽  
Nasal Mucosa ◽  
Biosynthetic Pathway ◽  
Fluorescein Isothiocyanate ◽  
Significant Time ◽  
Hoe 140 ◽  
Subsequent Activation

Gao, Xiao-Pei, Syed R. Akhter, and Israel Rubinstein.Ovalbumin increases macromolecular efflux from the in situ nasal mucosa of allergic hamsters. J. Appl. Physiol. 84(1): 169–176, 1998.—The purpose of this study was to determine whether bradykinin mediates ovalbumin-induced increase in macromolecular efflux from the nasal mucosa of ovalbumin-sensitized hamsters in vivo and, if so, whether thel-arginine/nitric oxide biosynthetic pathway transduces, in part, this response. We found that suffusion of ovalbumin onto the in situ nasal mucosa of ovalbumin-sensitized hamsters, but not of controls, elicited a significant time- and concentration-dependent increase in clearance of fluorescein isothiocyanate-labeled dextran (mol mass, 70 kDa; P < 0.05). HOE-140, but not des-Arg9,[Leu8]-bradykinin, and N G-l-arginine methyl ester (l-NAME), but not N G-d-arginine methyl ester, significantly attenuated ovalbumin-induced responses.l-Arginine, but notd-arginine, abolished the effects ofl-NAME.l-NAME also significantly attenuated bradykinin-, but not adenosine- induced increase in macromolecular efflux from the in situ nasal mucosa. Overall, these data suggest that ovalbumin increases macromolecular efflux from the in situ nasal mucosa of ovalbumin-sensitized hamsters, in part, by producing bradykinin with subsequent activation of thel-arginine/nitric oxide biosynthetic pathway.

Sign in / Sign up

Export Citation Format

Share Document