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Diabetologia(198l)21:452-459Diabetologia9Springer-Verlag1981Dose-KineticsofPancreaticGlucagonResponsestoArginineandGlucoseinSubjectswithNormalandImpairedPancreaticBCellFunctionR.
Assan1,S.
Efendic2,R.
Luft2andE.
CerasP1DiabetesDepartment,BichatHospital,Paris,France,2DepartmentofEndocrinology,KarolinskaHospital,Stockholm,Sweden,and3DepartmentofEndocrinologyandMetabolism,HadassahUniversityHospital,Jerusalem,IsraelSummary.
Pancreaticglucagonresponsestodifferentamountsofintravenousarginineandglucosewerestudiedin10insulin-dependentdiabetics,14healthycontrols(highinsulinresponders)and15subjectswithdecreasedinsulinresponsetoglucosebutnor-malintravenousglucosetolerance(lowinsulinre-sponders).
Thedose-kineticsoftheglucagonre-sponsewasstudiedbyusingfourdifferentargininedoses.
Thesuppressiveeffectofglucosewasevaluat-edbyinfusingthreeglucosedosesduringasubmaxi-malstimulationwitharginine.
Thediabeticsweretestedfirstwhenunderfairmetaboliccontrolandthenfollowingintensivetreatmentwithinsulintopro-ducenear-normalisationofbloodglucose.
Finally,fivesubjectsunderwentinsulin-inducedhypogly-caemia.
Thechangesinplasmaglucagonandblooda-amino-nitrogeninresponsetothefourargininedosesweresignificantlycorrelatedinallgroupsbuttheslopeofthedoseresponsecurvewassteeperinthepoorlycontrolled-diabeticsthaninthenon-diabetics.
Thesediabeticsdisplayedhigherfastingplasmaglu-cagonvaluesthanhealthycontrols(highinsulinre-sponders)(224+4versus151+22pg/ml,p<0.
01),higherplasmaglucagonresponsestoarginineandanabsenceofinhibitionbyglucoseofthearginine-stimulatedglucagonrelease.
Instrictlycontrolleddiabeticpatients,fastingplasmaglucagonlevels(176+16pg/ml)werenotsignificantlydifferentfromhealthycontrols,theglucagonresponsetoargininereturnedtothenormalrange,AcellsuppressibilitybyglucosewasrestoredandAcellstimulationbyhypo-glycaemiareappeared.
Inthelowinsulinresponders,fastingplasmaglucagonwasnotdifferentfromthatofhighresponders(107+12pg/ml),theslopeofthedoseresponsecurvetoargininewassimilarinbothgroupsandtheAcellswereinhibitedbyglucosetoasimilarextent.
TheseresultssupporttheconceptthatisletAcelldysfunctionindiabetesisnotaprimaryphenomenon.
Keywords:Glucagon,Aceil,lowinsulinresponders,diabetes.
ThecauseoftheisletAcellabnormalitiesandtheirimportanceinthepathophysiologyofdiabetesmelli-tusremainscontroversial[1-5].
IthasbeensuggestedthatAcelldysfunction,whichisasecondaryphenomenoninexperimentaldiabetes,mightbeaprimarydefectinhumandiabetes[1].
Ifthishypothe-sisiscorrect,Acelldysfunctionmightbepresentinpotentiallydiabeticsubjectsbeforetheestablishmentofovertmetabolicdisturbances.
Onthecontraryifhyperglucagonaemiaisinducedbythemetabolicchangesofdiabetes,Acellfunctionshouldbenormalinovertdiabeticsinwhomstrictcontroloftheirdis-easeisachieved.
Thishasrecentlybeendemonstratedinsomegroupsofaggressivelytreatedpatients[5-8].
InthepresentstudyisletAcellfunctionhasbeenevaluatedusingvariousdosesofarginineandglucoseinthefollowinggroupsofpatients.
First,lowinsulinresponderswithanormalglucosedisappearancebutdecreasedinsulinresponsetoglucoseinfusionwhohavepreviouslybeendemonstratedtohaveahigherprobabilityofdevelopingdiabetes[9,10].
Second,in-sulindependentdiabeticsbeforeandafterstrictgly-caemiccontrolandthird,normalhealthysubjects.
SubjectsandMethodsSubjectsThecharacteristicsofthesubjectsareshowninTable1.
Sexdistri-bution,agerangeandpercentageidealbodyweightweresimilarinallgroups.
Nosubjectwasobese.
Thenon-diabeticsubjectswereclassifiedashighorlowinsulinrespondersbeforethepresentstudyaccordingtotheirinsulinresponsetoglucoseinfusion[9,10].
TheKvalueoftheIVglucosetolerancetestwasabove1.
0inallsubjects.
0012-186X/81/0021/0452/$01.
60R.
Assanetal.
:ACellResponsesinSubjectswithNormalandImpairedBCellFunction453Table1.
CharacteristicsofthesubjectsstudiedGroupAgeIdealbodyKvalueDurationof(years)weight(%)(%/rain)diabetes(years)Highinsulin32+292+32.
7+0.
2responders(n=14)Lowinsulin37+2102+11.
6+0.
1a-responders(n=15)Diabetics28+3101+2-10_+2(n=10)Resultsarepresentedasmean_+SEM.
~statisticalsignificanceofdifferenceswiththehighinsulinresponders:p<0.
01.
Numbersofsubjectsareindicatedinparentheses.
%idealbodyweightwascal-culatedaccordingtoStatistBullMetropLifeInsurCo[1959]However,thelowinsulinresponderspresentedsignificantlylowerKvaluesthanthehighrespondersashaspreviouslybeendemon-stratedinalargergroupofsubjects:1.
6___0.
1versus2.
7_+0.
2%/min[10l.
Alldiabeticpatientshadbeenketoticonadmissionandwerein-sulin-dependent.
Renalandhepaticfunctionwasnormalasas-sessedbyserumcreatinineandalkalinephosphataseconcentra-tions.
Nosubjectsweretakinganymedicationotherthaninsulinatthetimeofstudy.
Nonehadotherchronicdisease.
ThepatientsweretestedfirstwhileonasingledoseofLenteinsulin(2540U),providingfaircontrolofglycaemia.
Thebloodglucosewas8.
2_+1.
3mmol/1fastingand13.
7_+1.
3mmol/12hafterlunch.
Asecondtestwasperformedafteroneweek&rigidcontrolwithIso-phaneinsulin(20-34Uat08.
00hand10-34Uat20.
00h).
Thebloodglucosewas4.
3_+0.
6mmol/lfastingand6.
9_+1.
3mmol/12hafterlunch(valuescollectedonsevendifferentdays).
Inaddi-tionaslowIVinfusionofinsulin(Actrapid1.
7U/h)wasmain-tainedforthe12hprecedingandduringthetestinordertomain-tainbloodglucoselevelsclosetonormalvalues.
InvestigationsAlltestswereperformedwiththeinformedconsentofthesubjectsandinaccordancewiththeprinciplesoftheDeclarationofHel-sinki.
ArginineHC1(Vitrum,Stockholm,Sweden)wasadministeredIVasarapidinjectionfollowedbyaconstantrateinfusionfor30rain.
Fourdoseswereused:l)0.
12mmol/kgbodyweightasabolus,followedbyaninfusionof0.
01mmol.
kgi.
min-l;2)0.
24mmol/kgbolusand0.
02mmol9kg-l9rain-Iinfusion;3)0.
72mmol/kgbolusand0.
04retool.
kg-I9rain-Iinfusion;4)1.
08mmol/kgbolusand0.
07retool.
kg-l.
min-linfusion.
ThesetestsarereferredtobelowasarginineI,II,IIIandIVrespec-tively.
PancreaticAcellinhibitionwasstudiedbycombiningglucoseadministrationwitharginineIII.
Thefollowingglucosedoseswereused:0.
55mmol9kg-~9rain-lfor30min;1.
38mmol/kgbolusand0.
05mmol.
kg-~.
min-~;2.
75mmol/kgbolusand0.
11mmol9kgl.
min-lThesearedesignatedasglucoseI,II,andIII,respectively.
Thefourargininedosesweretestedin14highinsulinrespon-ders,10lowinsulinrespondersand10diabetics.
Theglucose+ar-gininetestswereperformedinfiveofthehighrespondersandfiveofthelowresponders.
Inthe10diabetics,Acellstimulationbyargi-nineIIlandinhibitionbyglucoseIIIwereperformedbeforeandduringoptimisedcontrol.
Finally,fiveofthesediabeticsunderwentinsulin-inducedhypoglycaemia,obtainedbyIVinfusionof20UActrapidover30rain.
Alltestswereperformedinthesupinepositionat8.
00-10.
00hafteranovernightfast.
Atleastoneweekelapsedbetweenconsecu-tiveinvestigations.
Venousbloodsampleswerecollectedintochilledheparinisedtubes,handledappropriatelyforfurtherassays(seebelow)andthencentrifugedat+4~C.
Thesupernatantswerestoredat-20~Cuntilprocessing.
Glucosewasmeasuredinwholebloodbyaglucoseoxidasemethod[11];a-amino-nitrogen(a-NH2)bythecuprizonemethod[12]afterdeproteinisationwith5%(w/v)trichloraceticacid(0.
5mlfor0.
1mlblood).
Alaninewasde-terminedbyanenzymaticfluorimetricmethod[13]afterdeprotein-isationof0.
5mlbloodwith0.
5ml7.
5%(w/vperchloricacid).
Aprotinin(2,000U/1mlblood)wasaddedtothesamplesintendedforhormoneassay.
Plasmaimmunoreactiveglucagon(IRG)andinsulinweredeterminedbyradioimmunoassay,usingantiserum30Kforglucagon(ProfessorR.
H.
Unger,Dallas,Texas)withoutpri-orextractionofplasmasamples[14].
Thelowestamountofglucagonstandardwhichgaveasignifi-cantvariationfromthezerostandardofthebound/freeratiowas7pg/ml,correspondinginwholeplasmatoalowestdetectablevalueof21pg/ml.
Interassayvariationwaslessthan5%.
Resultsarepresentedasmean+SEMforeachtimepoint.
Thesumoftheglucagonvaluesduringindividualexperimentswascal-culatedtogivetheintegratedglueagonresponsefor90min.
Sim-ilarlythesumofthesubstratevariationsfrombasalvalueswascal-culatedineachindividualexperimenttogivethenetincreaseorde-creaseofbloodglucose,a-NH2andalanine.
Standardstatisticalmethodswereusedforanalysisofresults.
Non-parametricstatisticswereusedforcomparisonsofthesummed(integrated)responsesandofthesumsofvariationsfrombasalvalues[15].
ResultsBasalValuesBasalvalueswerecalculatedforeachsubjectbytak-ingthemeanofindividualmeasurementsonfivetoeightdifferentoccasions.
Innon-diabeticsubjectstherewasnosignificantdifferencebetweenhighandlowinsulinresponderswithrespecttofastingbloodglucoselevels(4.
2+0.
1versus4.
3_+0.
1mmol/1);a-NH2(5.
3+0.
2versus5.
9__+0.
2mmol/1);alanine(359_+29versus361+40mmol/1)andinsulin(24.
0_+0.
7versus24.
0_+1.
4mU/1).
Plasmaimmuno-reactiveglucagon(IRG)levelswerenotsignificantlydifferentbetweenlowinsulinrespondersandthehighresponders(107+12versus151+22pg/ml).
Thediabeticpatientsdifferedsignificantlyfromthetwoothergroupsforfastingbloodglucose(9.
2_+0.
3mmol/1);a-NH2(4.
8_+0.
2retool/l)andplasmaIRG(224_+4pg/ml).
Duringtheexcellentcontrolofthediabeticsthedifferencesforglucose(4.
3___0.
02mmol/1)andIRG(176___16pg/ml)disap-peared,butnotfora-NH2(4.
7+0.
2mmol/l).
Bloodalaninewasnotdifferentfromtheothergroups(362_+18~tmol/1).
454R.
Assanetat.
:ACeltResponsesinSubjectswithNormalandImpairedBCellFunctionARGININEIARGININETrARGININE1~ARGININEIV15g/A14,'',IIII13,,,,''''i;IIr912',III,t~\lIII*10,I[II8,,'IIIII~I9".
+-L";-:/'i4J.
,.
rl,r'0306090030609003060900306090mi.
Fig.
I.
Bloodco-amino-nitrogenduringarginineinfusionsinhighinsulinresponders(e),lowinsulinresponders(9andpoorlycontrolleddiabetics(9);asterisksindicatep<0.
05orlowerfromthecorrespondingvalueinhighresponders.
Thehatchedbarsindicatethedurationofarginineinfusion.
(seetextforthefourargininedoses)Table2.
Bloodglucose:basalvaluesandincreasesoverbasalduringarginineandarginine+glucoseinfusionsincontrolanddiabeticsub-jectsGroupsBasalvalues(retool/l)Sumofincreasesoverbasal(mmol/1-~-90rain-l)ArginineIArginineIIArginineIIIArginineIVArginineIIIArginineIIIArginineIII+glucoseI+glucoseII+glucoseIIlControlsubjectsHighresponders4.
20.
l0.
40.
6Lowresponders4.
30.
11.
10.
4DiabeticsubjectsFaircontrol9.
3_+0.
3u8.
42.
7aGoodcontrol4.
3_+0.
7-1.
60.
81.
010.
419.
5~0.
555.
02.
51.
91.
99.
238.
080.
0b8.
8+3.
9a19.
6+2.
7b26.
4+3.
0b-_130.
1+5.
0b5.
53.
6--45.
5+3.
5Increasesoverbasalrepresentthealgebraicsumsofvariationsfrombasalvalues(i.
e.
themeanoftimesamples15andzerorain)ascalcu-latedfromtimesamples+5,10,15,20,45,60and90rain.
ResultsarepresentedasmeanSEM.
Statisticalsignificanceofdifferenceswithhighinsulinrespondersap<0,01;bp<0.
001ArginineInfusionTestsIngeneral,duringthearginineloadingshigherblooda-NH2valueswereobservedinthelow-insulinre-spondersandlowervaluesinthediabeticswhencom-paredwiththehighinsulinresponders(Fig.
1).
Themagnitudeoftheincreasewassimilarinallgroupsforanygivenincreaseinthedoseofarginineused.
Inhighinsulinresponders,bloodglucosedisplay-edtheusualslightrisefollowedbyaminordecrease.
Therisewasmorepronouncedinlowrespondersandevenmoresointhediabetics(Table2).
PlasmaIRGroseproportionallytotheargininedoseinallgroups,evenwiththelowestinfusionrate(Fig.
2).
Withthetwolowestargininedoses,peakva-lueswerereachedat5min,witharginineIIIandIVat30min.
PlasmaIRGreturnedtobaselineat90minorearlier,exceptinthecaseofarginineIV.
Inthediabet-icpatientsplasmaIRGwasalwayshigherthaninnon-diabeticsubjects.
Thedifferencesbetweendia-R.
Assanetal.
:ACellResponsesinSubjectswithNormalandImpairedBCellFunctionARGININEIARGININEI1ARGININElit0.
8"F/AP"/Z/Z'g/A0.
7-0.
6""x0.
5O(D<:~=o04:EO.
3-u')0.
2-0.
1-!
l,ltIiI,,l/'-~0306090PT/'/Z//7//~'g,/l'\-~--.
T~9-1/~-IIIi0306090306090P7/7/////~P~ARGININEI2P'ZZZ'/7//'/Z/~IiiIii030i-~/-~6090rain455Fig.
2.
Plasmaglucagonvariationsduringarginineinfusionsinhighinsulinresponders(@),lowinsulinresponders(9andpoorlycon-trolleddiabetics(A).
ResultsarepresentedasinFig.
lE2_Eg,%.
_igc~6]4I~~,~,io//.
V2o5'oBLOOD~-AMINO-NITROGENINCREMENTSHIGHINSULINzRESPONDERSo.
-"o-~40~n_30~_~2O"~,E10.
~OM4o.
-~301cac:,2D~{loca80~:+~t\~83(mmolI-~90mini')4LOWINSULINDIABETICRESPONDERSPATIENTSFig.
3.
Dose-responsecurvesrelatingtheglucagonresponses(sumofglu-cagonvaluesfor90rain)tothecorre-spondinga-amino-nitrogenin-creasesinhighinsulinresponders(1),lowinsulinresponders(O)anddiabetics(9Resultsarepresentedasmean+_SEM.
Equationsfordoseresponsecurveswere:y=1.
29logx+1.
34inhighinsulinresponders(n=14);y=1.
20logx+1.
03inlowinsulinresponders(n=10);y=2.
08logx+1.
30indiabetics(n=10)Fig.
4.
Algebraicsumofvariationsfrombasalvaluesofa-amino-nitro-gen,glucagon(IRG),glucoseandal-anineduringthe90rainofthetests.
Algebraicsumofvariationsfromba-salwascalculatedasinTables1and2.
Thefourcolumnsineachgroupofresultscorrespondtothefourdosesofarginine(seetextfordetailsonthearginineinfusions)beticsandhighinsulinrespondersweresignificantatafewtime-points.
Ontheotherhand,comparisonsbetweendiabeticsandlowinsulinrespondersyieldedsignificantdifferencesatalmostallsamplingtimes.
Nosignificantdifferenceswereobservedbetweenhighandlowresponders,butIRGresponsecurveswere,inmostinstances,lowerinthelowrespondersthaninhighresponders.
Therewasalinearrelationshipbetweentheinte-gratedIRGresponseover90rainandthelogofa-NH2increase(r=0.
98to0.
99;p<0.
05,Fig.
3).
Theslopewassteeperindiabeticsthaninnon-diabetic456R.
Assanetal.
:ACellResponsesinSubjectswithNormalandImpairedBCellFunctionTable3.
Plasmainsulin:basalvaluesandincreasesoverbasalduringarginineandarginine+glucoseinfusionsinthecontrolsubjectswithhighandlowinsulinresponsesGroupsBasalvaluesSumofincreasesoverbasal(txU9ml-L.
90min-1)(mU/l)ArginineIArginineIIArginineIIIArginineIVArginineIIIArginineII]ArginineIII+glucoseI+glucoselI+glucoselIIHighresponders24+153+_12102+13236+30255+29392+54540_+951062+118Lowresponders24-+152-+2470-+12106+29a125+29a246_+67333_+50445+60~ResultsarepresentedasinTable2.
aStatisticalsignificanceofdifferencesbetweenthetwogroups:p<0.
001subjects,butwassimilarinhighandlowinsulinre-sponders.
Biphasicinsulinresponseswereobtainedforalldosesofargininebothinhighandlowinsulinresponders.
Theincreasesininsulinandthea-NH2werehighlycorrelatedinbothgroups(r=0.
96and0.
97).
Theinsulinresponsewaslowerinlowre-spondersthaninhighresponders(Table3).
Thisdifferencewasevenmorestrikingconsideringthehigherbloodglucoseanda-NH2levelsinlowinsulinresponderstoarginineinallexperiments.
Arginineinfusionsexertedmodestnon-signifi-canteffectsonbloodalanineconcentrationinthenon-diabeticsubjects.
Incontrast,intheinsulindefi-cientpatientsIVarginineinducedadecreaseinala-nineconcentration(Fig.
4),whichwastime-related(Fig.
5)anddose-relatedwitha-NH2andIRGchanges(r=-0.
97and-0.
98respectively).
EffectsofInfusionsofGlucoseTogetherwithArginineAsshowninTable2,theincreasesinbloodglucoseweresignificantlyhigherinlowthaninhighinsulinresponders,andconsiderablymoresointhediabeticswithfairmetaboliccontrol.
Inthediabeticswithgoodcontrol,theincreasesinbloodglucoseconcentrationsweresimilartothoseofnormalsubjects(Table2).
Theblooda-NH2elevationfollowingargininewasnotin-fluencedbytheglucoseorinsulininfusions.
TheeffectofglucoseIIIontheglucagonresponsetoarginineIIIisshowninFigure6.
Asignificantde-creaseinplasmaglucagonwasobtainedbothinhighandinlowinsulinresponders.
Therewasalinearrela-tionshipbetweenthedegreeofinhibitionofglucagonsecretionandthelogofthecorrespondingincreaseinbloodglucosefollowingtheinfusionofthethreedosesofglucoseintothehighandlowinsulinrespon-ders(Fig.
7).
ThedegreeofAcellinhibitionbyglu-cosewassimilarinthesetwogroupsbutnoinhibitoryeffectofglucosecouldbedemonstratedinthediabet-icswithfaircontrol(Figs.
6and7).
However,whenthesepatientswereintensivelytreatedwithinsulin,fastingplasmaglucagonreturnedtowardsnormal0Iii0.
70.
6]~_o.
s-0.
4a30.
2o.
18--0~01~.
~,~E0"3510.
30~v/A~,RGININE]~-:UNCONTROLLEDDIABETIC.
Si,4-,""!
\,f.
,\.
~+'j*mi.
,556is30isgo'~0m~,Fig.
5.
Timecourseofa-amino-nitrogen,glucagon,glucoseandal-anineduringinfusionofarginineIVinpoorlycontrolleddiabetics(n=10).
Thehatchedbarindicatesthedurationofinfusion(176+16pg/ml)andthearginineinfusionsignifi-cantlysuppressedtheAcellresponsebothwithandwithouttheadministrationofglucose(Figs.
7and8).
Theadditionofglucosetoargininesignificantlyaugmentedtheinsulinresponsesinhighaswellaslowinsulinresponders(Table3).
EffectofInsulin-InducedHypoglycaemiaInsulin-inducedhypoglycaemiatoameanvalueof1.
9+_0.
1mmol/1infiveaggressivelytreateddiabetics,resultedinaplasmaIRGof220+33pg/mlat30min.
Thisvaluewassimilartothatobtainedafteranover-nightfastinthe10well-controlledpatients(176+16pg/ml).
R.
Assanetal.
:ACellResponsesinSubjectswithNormalandImpairedBCellFunction4570,7-0.
6-05-j=~'0.
4-vZ000.
3-~EO,2-u').
_I0.
I-HIGHRESPONDERSLOWRESPONDERSUNCONTROLLEDDIABETICSsIIIIY/IiII~,_,Jy--yLV/A11'530609'001530'6'09'0015306'09'0rainFig.
6.
PlasmaglucagonresponsetoarginineIII(closedsymbols)andarginineIII+glucoseIII(opensymbols)inhighinsulinresponders(O,n=14,O,n=12),lowinsulinresponders(V,n=10,V,n=6)anddiabetics(A,n=i0,A,n=10)inabsenceofgoodmetaboliccontrol.
HatchedbarsindicatethedurationofinfusionsU_l_Jo(.
3ZD_J(DZO-rz10-20-4O]506070o.
'ss:odo16oisoGLUCOSEINCREMENTOVERBASAL(retool1-190mln-1)Fig.
7.
InhibitionoftheglucagonresponsetoarginineIIIbyglu-coseI,IIandIII.
Theglucagonresponsetoarginine+glucose(sumofvaluesover90min)hasbeencalculatedaspercentageoftheresponsetoargininealone,andplottedagainsttheconcomitantincrementalbloodglucoselevels(sumofvaluesover90rain).
Highinsulinresponders(O,n=8),lowinsulinresponders(O,n=8),uncontrolleddiabetics(A,n=10)andtightlycontrolleddiabetics(A,n=10).
Resultsarepresentedasmean_+SEMDiscussionManyofourresultsconfirmfindingsthatarealreadywellestablished,suchasisletAcellhyperactivitydur-ingpoorcontrolofbloodglucoseindiabetes[16-17],increasedglucagonresponsetoamino-acids[17-20]andnon-suppressibilityofglucagonreleasebyglu-coseindiabetics[21].
Inadditionourdose-responsestudiessuggestthatindiabeticsitisthecapacityra-therthanthesensitivityoftheAcellresponsetoargi-ninewhichisaugmented.
ItisshownhereclearlythatAcelldysfunctionininsulindependentdiabeticsisrelatedtometabolicchangesanddisappearswithgoodcontrolofthebloodglucose.
Severalrecentstudieshavealsode-monstratedthatfastingglucagonlevels,theglucagonresponsetoarginine,anditssuppressibilitybyglu-cosecanberestoredtonormalornear-normalbyin-tensiveinsulintherapy[21-27].
Notonlyinsulinde-pendentpatientsbutalsoinsulinindependentdiabet-icsdemonstratehyperactivityofAcells[28].
Inthesepatientsonlyveryhighdosesofinsulincouldnormal-izetheglucagonlevels[28],butsuchsubjectsdisplayarelativeinsulindeficiencyandinsulinresistance.
SupraphysiologicaldosesofinsulinareusuallynecessarytoachieveAcellnormalizationindiabeticmanoranimals.
However,thismaysimplymeanre-458R.
Assanetal.
:ACellResponsesinSubjectswithNormalandImpairedBCellFunction07]060.
5-go,4o=~0.
3<(1.
2.
0,1IARGrNINEIlli30~'o9btXii3'06'0min9'0Fig.
8.
PlasmaglucagonresponsestoarginineIII(leftpanel)andarginineIII+glucoseIII(rightpanel)indiabeticsintheabsence(A,n=10)andinthepresence(A,n=10)oftightmetaboliccon-trol.
Resultsarepresentedasmean+SEMconstitutionofthehighinsulinconcentrationswhicharesupposedtoexistatthevicinityofAcells[29].
Whenminuteamountsofinsulinwerecontinuouslyinfusedintodiabeticsbyaglucosecontrolleddeviceoranopenloopsystem[8,27]severaldaysorweekswerenecessarytonormalizetheplasmaglucagonlev-el.
ThisinabilityofanacuteinsulininfusiontocorrectAcellreactiontoaminoacidsandglucoseindiabeticpatients[22-24]isnotnecessarilyinconflictwithourresultssincecompletenormalizationofthemetabolicstatecanhardlybeachievedundershort-termcondi-tions.
InsulinreducestheAcellresponseinvitrotoami-noacidsbythepancreasofalloxan-diabeticrats[32]andtoalesserextentbythepancreasfromstreptozo-tocin-diabeticrats[33].
Thisinsulinsensitivityofdia-beticAcells,albeitincompleteinsomecases,iscon-sistentwiththesuppressibilityofnormalAcellsbyglucoseonlyinthepresenceofinsulin.
OurobservationsinlowinsulinrespondersdonotsupporttheconceptofaprimaryAcellabnormalityininsulinindependentdiabetes.
Amarkedlyhigherprobabilitytodevelopdiabeteshasbeenestablishedbythefollow-upofthesesubjectsovera1-10yearpe-riod[10],whichstronglysuggeststhatthisconditionissomehowrelatedtoinsulinindependentdiabetes.
ThelowinsulinrespondersdisplayednormalfastingglucagonlevelsandanormalAcellsuppressionofglucose.
TheirAcellresponsestoargininewere,ifanything,slightlylowerthannormal,possiblybe-causeoftheslightlyhigherbloodglucosevaluesfol-lowingarginineinfusion.
Ourfindingsareinagree-mentwithotherresultsintheliterature.
Thus,normalAcellresponsetoarginineandtoglucosewasob-servedinnon-diabeticPimaIndianswithbothpar-entsdiabetic[30,31,34],inthemothersofbigneo-rtateswithgestationaldiabetes[35]andinamonozy-gotictripletwithtwodiabeticbrothers,whowasstud-iedfor2yearsbeforetheappearanceofdiabetes[36].
Theseresultsareatvariancewithtwootherstudiesonthediscordantmonozygotictwinsofdiabetics[37]andfirstdegreerelativesofdiabetics[38]wherethein-sulinresponsetoglucosewasslightlyimpairedandtheglucagonwasnotsuppressed.
Thefindingofsomewhatlowerfastingandpost-arginineglucagonlevelsinourlowinsulinrespondersisofinterest.
Itwasdemonstrated[39]thatthesesub-jectshavealowerthannormalsplanchnicglucoseproductionrate,probablythuspartiallycompensat-ingfortheirinsulindeficiency.
Whetherthesetwoob-servationsarecausallyinterrelatedcannotbedecidedfromthepresentstudy.
Oncediabetesisestablishedglucagonoversecre-tionmayplayanimportantroleinaggravatingthecharacteristicmetabolicdisturbances[40-48]butourresultssupporttheideathatAcelldysfunctionisnotaprimarycauseofthedisease.
References1.
UngerRH(1976)Diabetesandthealphacell.
Diabetes25:136-1512.
GerichJE,LorenziM,KaramJH,SchneiderV,ForshamPH(1975)Abnormalpancreaticglucagonsecretionandpost-prandialhyperglycaemiaindiabetesmellitus.
JAmMedAssoc234:159-1653.
FeligR,WahrenT,SherwinR,HendterR(1976)Insulin,glu-cagonandsomatostatininnormalphysiologyanddiabetesmellitus.
Diabetes25:1901-10994.
GerichJE,LangloisM,NoaccoC,KaramJH,ForshamPH(1973)Lackofglucagonresponsetohypoglycaemiaindia-betes:evidenceforanintrinsicpancreaticalpha-celldefect.
Science182:171-1735.
GeriehJE,TsalikianE,LorenziM,KaramJH,SchneiderV,GustafsonG,BohannonNV(1975)NormalizationoffastinghyperglucagonaemiaandexcessiveglucagonresponsestoI.
V.
arginineinhumandiabetesmellitusbyprolongedperfusionofinsulin.
JClinEndocrinolMetab41:1178-11806.
RaskinP,UngerRH(1978)Effectsofinsulintherapyontheprofileofplasmaimmunoreactiveglucagoninjuveniletypeandadult-typediabetics.
Diabetes27:411~197.
RaskinP,UngerRH(1978)Hyperglucagonaemiaanditssup-pression.
NEnglJMed299:433M368.
RaskinR,PietriA,UngerRH(1979)Changesinglucagonlevelsafter4to5weeksofglucoregulationbyportableinsulininfu-sionpumps.
Diabetes28:1033-10359.
CerasiE,LuftR(1967)Theplasmainsulinresponsetoglucoseinfusioninhealthysubjectsandindiabetesmellitus.
ActaEn-docrino155:278-30410.
CerasiE,LuftR(1967)Follow-upofnon-diabeticsubjectswithnormalanddecreasedinsulinresponsetoglucoseinfusion.
Firstreport.
HormMetabRes(Suppl5):l11-12011.
HuggetASG,NixonDA(1957)Useofglucoseoxidase,peroxi-dase,andO-dianisidineindeterminationofbloodandurinaryglucose.
Lancet2:368-370R.
Assanetal.
:ACellResponsesinSubjectswithNormalandImpairedBCellFunction45912.
MalangeauP,BourdonR,NicaiseAM,MassonB(1963)Do-sagedesacidesaminrsdanslesliquidesdel'organisme.
AnnBiolClin21:3-913.
WilliamsonDH(1970)Alanine.
In:BergmeyerHU(ed)Meth-odenderenzymatischenAnalyse.
VerlagChemie,Weinheim1364-137314.
AssantLTchobroutskyG,DerotM(1971)Glucagonradioim-munoassay,technicalproblemsandrecentdata.
HormMetabRes(Suppl3):82-9015.
SnedecorGW(1956)Statisticalmethods,5thed.
TowaStateCollegePress16.
AssanR,HautecouvertureM,GuillemantS,DauchyF,ProtinP,DerotM(1969)Evolutiondeparam+treshormonaux(glu-cagon,cortisol,hormonesomatotrope)et~nergrtiques(glu-cose,acidesgraslibres,glycrrol)dans10acidocrtosesdiab6-tiquesgravestraitres.
PatholBiol17:1095-110517.
AssanR,RosselinG,DrouetJ,DolaisJ,TchobroutskyG(1966)Tauxplasmatiqueduglucagonchezlesdiabrtiques.
AnnEn-docrinol(Paris)27:6-1218.
UngerRH,Aguilar-ParadaE,MfillerWA,EisentrautAM(1970)Studiesofpancreaticalphacellfunctioninnormalanddiabeticsubjects.
JClinInvest49:837-84819.
MfillerWA,FaloonaGR,Aguilar-ParadaE,UngerRH(1970)Abnormalalphacellfunctionindiabetes:responsestocarbo-hydrateandproteiningestion.
NEnglJMed283:109-11520.
GerichJE,LangloisM,NoaccoC,LorenziM,KaramJH,ForshamPH(1976)Comparisonofthesuppressiveeffectsofelevatedplasmaglucoseandfreefattyacidlevelsonglucagonsecretioninnormalandinsulin-dependentdiabeticsubjects.
JClinInvest58:320-32521.
OhnedaA,IshiiS,HorigomeK,YamagataS(1975)Glucag0nresponsetoarginineaftertreatmentofdiabetesmellitus.
Dia-betes24:81I-81922.
UngerRH,MadisonLL,MfillerWA(1972)Abnormalcellfunctionindiabetes.
Responsetoinsulin.
Diabetes21:301-30723.
BraatenJT,FaloonaGR,UngerRH(1974)Theeffectofinsulinonthealpha-cellresponsetohyperglycaemiainlong-standlngalloxandiabetes.
JClinInvest53:1017-102124.
RaskinP,AydinI,UngerRH(1976)Effectofinsulinontheex-aggeratedglucagonresponsetoargininestimulationindia-betesmellitus.
Diabetes25:227-22925.
RaskinP,FujitaY,UngerRH(1975)Effectofinsulin-glucoseinfusionsonplasmaglucagonlevelsinfastingdiabeticsandnon-diabetics.
JClinInvest56:1132-113826.
GerichJE,LorenziM,TsalikianE,BohannonNV,SchneiderV,KaramJH,ForshamPH(1976)Effectsofacuteinsulinwith-drawalandadministrationonplasmaglucagonresponsestoin-travenousarginineininsulin-dependentdiabeticsubjects.
Dia-betes25:955-96027.
KernerW,PfeifferEF(1977)Glucagonsecretionindiabeticsduringglucose-controlledinsulininfusion.
Diabetologia13:40828.
UngerRH,MadisonLL,MUllerWA(1972)Abnormalalpha-cellfunctionindiabetics:responsetoinsulin.
Diabetes21:301-30729.
UngerRH,RaskinP,SrikantCG,OrciL(1977)GlucagonandtheA-cell.
RecProgHormRes33:47730.
AronoffSL,BennettPH,RushforthNB,MillerM,UngerRH(1976)Arginine-stimulatedhyperglucagonaemiaindiabeticPimaIndians.
Diabetes25:404-40731.
AronoffSL,BennettPH,UngerRH(1977)Immunoreactiveglucagon(IRG)responsetointravenousglucoseinpre-dia-betesamongPimaIndiansandnormalCaucasians.
JClinEn-docrinolMetab44:968-97232.
PagliaraAS,StillingsSN,HaymondMW,HoverBA,Mat-schinskyFM(1975)Insulinandglucoseasmodulatorsoftheamino-acid-inducedglucagonreleaseintheisolatedpancreasofalloxanandstreptozotocindiabeticrats.
JClinInvest55:244-25533.
WeirGC,KnowltonSD,AtkinsRF,MacKennanKX,MartinDB(1976)Glucagonsecretionfromtheperfusedpancreasofstreptozotocin-treatedrats.
Diabetes25:275-28234.
BennettPH,AronoffSL,UngerRH(1976)Evidenceforanin-sulin-independentalpha-cellabnormalityinhumandiabetes.
Metabolism25:1527-152935.
TurnerRC,HarrisE,BloomSR,WrenC(1977)Relationshipoffastingplasmaglucoseconcentrationtoplasmainsulinandglu-cagonconcentrations.
Studiesinlatentdiabeticsandwomenwhohaveproducedlarge-for-datebabies.
Diabetes26:166-17136.
GandaOP,SoeldnerJS,GleasonRE,SmithTM,KiloC,Wil-lansonJR(1977)Monozygotictripletswithdiscordancefordi-abetesmellitusanddiabeticmicroangiopathy.
Diabetes26:469-47937.
DayJL,TattersallRB(1975)Glucagonsecretioninunaffectedmonozygotictwinsofjuvenilediabetics.
Metabolism24:145-15138.
KirkRD,DunnPJ,ReavenDW,DonaldRA(1975)Abnormalpancreaticalpha-cellfunctioninfirst-degreerelativesofknowndiabetics.
JClinEndocrinolMetab40:913-91639.
CerasiE,WahrenJ,LuftR,FeligP,HendlerR(1973)Theregu-lationofsplanchnicglucoseproductioninsubjectswithlowin-sulinresponse.
AcompensatorymechanisminprediabetesEurJClinInvest3:193-20040.
CherringtonA,VranicM(1974)EffectofinteractionbetweeninsulinandglucagononglucoseturnoverandFFAconcentra-tioninnormalanddepancreatizeddogs.
Metabolism23:729-74441.
SherwinR,WahrenJ,FeligP(1976)Evanescenteffectsofhypoandhyperglucagonaemiaonbloodglucosehomeostasis.
Me-tabolism25:1381-138342.
BomboyJD,LewisSB,LacyWW,Sinclair-SmithBC,Liljen-quistJE(1977)Transientstimulatoryeffectofsustainedhyper-glucagonaemiaonsplanchnicglucoseproductioninnormalanddiabeticman.
Diabetes26:1777-178443.
RaskinP,UngerRH(1977)Effectsofexogenoushypergluca-gonaemiaininsulin-treateddiabetics.
Diabetes26:1034-103944.
BarnesAJ,BloomSR,MashiterK,AlbertiKGMM,SmytheP,TurnellD(1977)Persistentmetabolicabnormalitiesindiabetesintheabsenceofglucagon.
Diabetologia13:71-7545.
DobbsR,SakuraiH,SazakiH,FaloonaG,ValverdeI,BaetensD,OrciL,UngerRH(1975)Glucagon:roleinthehypergly-caemiaofdiabetesmellitus.
Science187:544-54746.
McGarryJD,FosterDW(1977)Hormonalcontrolofketogen-esis.
ArchInternMed137:495-50147.
RizzaRA,GerichJE(1979)Persistenteffectofsustainedhyper-glucagonaemiaonglucoseproductioninman.
JClinEndocri-nolMetab48:352-35548.
RizzaR,VerdonkC,MilesJ,ServiceFJ,GerichJE(1979)Effectofintermittentendogenoushyperglucogonaemiaonglucosehomeostasisinnormalanddiabeticman.
JClinInvest63:1119-1123Received:28January1980andinrevisedform:17July1981Dr.
R.
AssanDiabetesDepartmentBichatHospitalF-75018Paris,France