一氧化氮供體對穿膜肽吸收

Nitricoxidedonorscanenhancetheintestinaltransportandabsorptionofinsulinand[Asu1,7]-eelcalcitonininratsAuthor：GihanFetih

FawsiaHabib

NaokiOkada

TakuyaFujita

MohammedAttia

AkiraYamamoto

JournalofControlledReleaseVolume106,Issue3,2September2005,Pages287–297編輯pptThecharacteristicsofthreeNOdonors,NOC5NOC12SNAPasabsorptionenhancersforpeptidedrugswereexaminedinrats.Insulinand[Asu1,7]-eelcalcitonin(ECT)wereusedasamodeldrugtoinvestigatetheeffectivenessofthetestedenhancers.Experimentalmethod：amodifiedUssingchambermethodandaninsituclosedloopmethod.Conclution：NOdonorspossessexcellenteffectivenessfortheuseasabsorptionenhancersofpeptidedrugsandtheyareveryeffectiveatlower.Abstract編輯pptEssaymapNOC5NOC12SNAPNO

ECT

InsulinConcentrationAbsorptionpositionNOscavengerNitricoxidedonorsNOpeptidedrugsNOscavenger編輯ppt1、Experimentalnotes-1：threeNOdonors：3-(2-hydroxy-1-(1-methylethyl)-2-nitrosohydrazino)-1-propanamine(NOC5),C6H16N4O2N-ethyl-2-(1-ethyl-2-hydroxy-2-nitrosohydrazino)-ethanamine(NOC12)

C6H16N4O2S-nitroso-N-acetyl-DL-penicillamine(SNAP)modeldrugs：

Insulinand[Asu1,7]-eelcalcitonin(ECT)2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazole-1-oxyl3-oxide,sodiumsalt(carboxy-PTIO),NOscavenger:C7H12N2O4S編輯ppt1

Experimentalnotes-2：largeintestinecolon5cm3cmCutoutCutoutjejunum

ileumSmallintestine編輯ppt1Experimentalnotes-3：Papp

=

(dXR/dT)

×

(1/A·Co)XRistheamountofdruginmolesinthereceptorsideAisthediffusionareainsquarecentimetersCoistheinitialconcentrationofdruginthedonorsidePappistheapparentpermeabilitycoefficientincentimeterspersecondThepharmacologicalavailability(PA%)Theareaabovethehypoglycemic(orhypocalcemic)effect(%)-timecurve(AAC)編輯ppt2、Methods-1IllustrationofabiopsysampleloadedintotheUssingchamber.Theintestinalbiopsywasplacedinthecenterofthesupportingdisc,coveringthetransversallumenoftheUssingchambercompletelyanddividingthesolutionintotwocompartments.drugsolutionPBSamodifiedUssingchambermethod編輯ppt2、Methods-2aninsituclosedloopmethodinsulin(0.1IU/rat,ECT(0.1μg/rat)].AclosedloopNOdonorsobtaintheplasmafraction(100μl)PlasmaglucoseconcentrationstheglucoseoxidasemethodPlasmacalciumconcentrationsWakoCalciumCtest編輯ppt2、Methods-3Atpre-determinedtimesupuntil180min240μlintestinalmucosaltissuehomogenates360μlof0.02mMinsulinsolutionNOdonors(5mM).Theresultingmixturewascentrifugedat10,000rpmfor5mintoremovetheprecipitatedprotein編輯pptResult-3.1EffectofNOdonorsonthepermeabilityofinsulinacrosstheintestinalmembranesFig.1.RegionaldifferencesintheeffectsofNOdonors(0.1mM)onthepermeabilityofinsulinacrossdifferentintestinalmembranes.編輯pptFig.2.EffectofvariousconcentrationsofNOdonorsonthepermeabilityofinsulinacrossthecolonicmembrane

(●)NOC5,(▲)NOC12and(■)SNAPResult-3.1EffectofNOdonorsonthepermeabilityofinsulinacrosstheintestinalmembranesSNAPwasthemosteffectiveenhancerTheabsorption-enhancingeffectswereconcentration-dependentovertherangeof0.01to0.1mM.編輯pptResult-3.2.Effectofcarboxy-PTIOontheabsorptionenhancingeffectofNOdonorsFig.3.Effectofcarboxy-PTIO(c-PTIO)onthepermeabilityofinsulinacrossthecolonicmembraneinthepresenceofNOThesefindingssuggestedthattheabsorptionenhancingeffectsofNOdonorsoninsulinpermeabilitymightbemediatedbytheactionofNO.編輯pptResult-3.3.

EffectsofNOdonorsontheintestinalabsorptionofinsulinFig.4.Concentration-timeprofilesofglucoseinplasmafollowingadministrationofinsulinwithorwithoutNOdonorstodifferentsites.Keys:(○)control,(●)NOC5,(▲)NOC12,(■)SNAP.TheextentofabsorptionwasgreatlyimprovedbyNOdonorsfromallloops,butthegreatestenhancementwasobtainedinthecolon.編輯pptResult-3.3.EffectsofNOdonorsontheintestinalabsorptionofinsulin編輯pptFig.5.

EffectofvariousconcentrationsofNOdonorsonthepharmacologicalavailability%(PA%)followingadministrationofinsulin(20IU)totheratcolon..DottedlinerepresentsthelevelofinsulinPA%withoutNOdonors(control).Keys:(●)NOC5,(▲)NOC12and(■)SNAPResult-3.3.EffectsofNOdonorsontheintestinalabsorptionofinsulinConcentrationdependencyofNOdonorswasexaminedforthecolonicabsorptionofinsulin編輯pptFig.6.

Effectof10mMcarboxy-PTIO(c-PTIO)onthepharmacologicalavailability%(PA%)ofinsulinafteradministrationtotheratcolonwithNOdonors(5mM).,significantlydifferentcomparedwiththecontrol,(n.s.)notsignificantlydifferentcomparedwiththecontrol.Result-3.3.

EffectsofNOdonorsontheintestinalabsorptionofinsulintheabsorptionenhancingeffectofNOdonorsoninsulinabsorptionmaybemediatedbytheactionofNO.編輯pptResult-3.4.StabilityofinsulinintheintestinalmucosalhomogenatesinthepresenceofNOdonorsFig.7.

EffectofNOdonors(5mM)onthedegradationofinsulin(0.02mM)inthesmallandlargeintestinalhomogenates.Eachpointisthemeanoffourexperiments.Keys:(○)control,(●)NOC5,(▲)NOC12,(■)SNAP.編輯pptResult-3.4.StabilityofinsulinintheintestinalmucosalhomogenatesinthepresenceofNOdonorsNOdonorsdidnotreducethedegradationofinsulininanyofthehomogenates編輯pptResult-3.5.EffectsofNOdonorsontheintestinalabsorptionofECTFig.8.Concentration-timeprofilesofcalciuminplasmafollowingadministrationofECTwithorwithoutNOdonorstodifferentsites.Keys:(○)control,(●)NOC5,(▲)NOC12,(■)SNAP.編輯pptResult-3.5.EffectsofNOdonorsontheintestinalabsorptionofECTthesiteofmaximumenhancereffectivenesswasthecolon.TherankorderofNOdonorswasalsothesame(SNAP