12 Kuliah 1. Fungsi Mekanik Sistem Pencernaan

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FUNGSI MEKANIK SISTEM PENCERNAAN Rahmatina B. Herman Bagian Fisiologi Fakultas Kedokteran Universitas Andalas

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Transcript of 12 Kuliah 1. Fungsi Mekanik Sistem Pencernaan

FUNGSI MEKANIKSISTEM PENCERNAANRahmatina B. HermanBagian FisiologiFakltas Ke!okteran Uni"ersitas An!alasIntro!#tionThe $rimar% &n#tion o& the !igesti"e s%stem is to trans&er ntrients' (ater an! ele#trol%tes &rom the ingeste! &oo! into the )o!%*s internal en"ironment The ingeste! &oo! is essential as+, an energ% sor#e &rom (hi#h the #ells #an generate ATP to #arr% ot their $arti#larenerg%,!e$en!ent a#ti"ities, a sor#e o& )il!ing s$$lies &or the rene(alan! a!!ition o& )o!% tissesThe !igesti"e s%stem $er&orms+..-Intro!#tion.. Motilit% along gastrointestinal tra#t /. Se#retion o& !igesti"e 0i#es1. 2igestion o& &oo!3.A)sor$tion the small a)sor)a)le nitsE4#retion o& the (aste materialsReglation o& !igesti"e &n#tion throgh neral re5e4es an! hormonal $ath(a%sProte#tion against an% !amages For )asi# !igesti"e $ro#esses+General Prin#i$le o& Gastrointestinal Motilit%Chara#teristi#s o& gastrointestinal (all+6a%ers o& the (all 7in(ar!8+, Serosa+ #ontines onto mesenter% , Ms#laris+ smooth ms#les9 longit!inal la%er+ oter9 #ir#lar la%er+ inner,S)m#os+ smooth ms#les9 ms#laris m#osae' sall% longit!inal, M#osaEa#h la%er &n#tions as s%n#%tim-..General Prin#i$le o& Gastrointestinal Motilit%-..General Prin#i$le o& Gastrointestinal Motilit%Basi# Ele#tri#al A#ti"it%Slo( :a"es+,n!lating#hangesintheresting mem)rane $otential 7,;< , =< m>olts8 , intensit%+ ; ? .; m>olts, &re@en#%+ 1,./Amin 71 in the )o!% o& thestoma#h'./inthe!o!enm'B,Cin the terminal ilem8 , might )e #ase! )% a slo( n!lation o& theso!im,$otassim $m$ing a#ti"ities, rarel% #ase ms#le #ontra#tion, Basi#Ele#tri#alRh%thm7BER8D#ontrol thea$$earan#e o& intermittent $eristalti# -..Basi# Ele#tri#al A#ti"it%S$ike Potential+, is tre a#tion $otential,generate! at the $eaks o& the slo( (a"es' (henthe $eaks rise a)o"e , 3< m>olts, the !e$olariEing $ortion o& ea#h s$ike $otential is!e to CaFF in54 throgh Ca,Na #hannel an!re$olariEing $ortion is !e to KFeG4 , stimlation )% stret#h' a#et%l#holine' $aras%m$atheti#s' an! s$e#iH# GI hormones,rate+ .,.ago"agal re5e4+ re!#es the tone in the ms#lar (all o&the )o!% o& the stoma#hB. Mi4ing the &oo! (ith the gastri# se#retions ntil it &orms a semi5i! mi4tre,$eristalti# #onstri#tor rings,$ro$lsi"e mo"ement to(ar! $%lors ,retro$lsionC.Em$t%ing o& the stoma#h ,role o& antrm+ #onstri#tion mo"ement ,role o& $%lors 7$%lori# s$hin#ter8+ $%lori# $m$Hnger #ontra#tions+ hnger $ang ,sall% !o not )egin ntil ./,/3 hors a&ter the last ingestion , rea#h greatest intensit% in 1,3 !a%s an! the gra!all% (eaken-..Motor Fn#tions o& The Stoma#hReglation o& Stoma#h Em$t%ingThe (eak gastri# &a#tors that $romote em$t%ing+, EJe#t o& gastri# &oo! "olme on rate o& em$t%ing9 "ago"agal an! m%enteri# re5e4es , EJe#t o& hormone gastrinThe $o(er&l !o!enal &a#tors that inhi)it em$t%ing+, Enterogastri# ner"os re5e4es &rom !o!enm9 !egree o& !istention o& !o!enm9 es$e#iall% sensiti"e to the $resen#e o& irritant an! a#i!s9 also )reak!o(n $ro!#ts o& $rotein !igestion9 !egree o& osmolalit%, Hormonal &ee!)a#k &rom !o!enm#hole#%stokinin' se#retin' gastri# inhi)itor% $e$ti!eMotor Fn#tion o& The Small IntestineA.Mi4ing #ontra#tions 7segmentation #ontra#tions8 ,BER (ith )a#kgron! e4#itation )% the ENSB.Pro$lsi"e mo"ements 7$eristalsis8,in#rease! !e to+O!istention Ogastroenteri# re5e4es throgh the ENS Ohormone gastrin' #hole#%stokinin' inslin' serotonin Oirritation$eristalti# rsh !iarrhea ,!e#rease! !e to+Ohormone se#retin an! gl#agon O$eristalsis in the &asting+ migrating motor #om$le4C.Mo"ements #ase! )% the ms#laris m#osa an! ms#le H)ers o& the "illi-..Motor Fn#tion o& The Small IntestineSegmentation mo"ement o& the small intestineMotor Fn#tion o& The ColonA.Mi4ing mo"ements , hastrationsB.Pro$lsi"e mo"ements ? Mmass mo"ementsN ,slo( anal(ar! mo"ement o& hastral #ontra#tions ,mass mo"ement + mo!iH#ation o& $eristalsis initiate!)%+ O gastro#oli# an! !o!eno#oli# re5e4es O irritation an! !istention O $aras%m$atheti# stimlationC.2e&e#ation + ,intrinsi# !e&e#ation re5e4 ,$aras%m$atheti# !e&e#ation re5e4 ,internal anal s$hin#ter ,e4ternal anal s$hin#ter 7"olntar%8-..Motor Fn#tion o& The Colon2e&e#ation re5e4Atonomi# Re5e4es That AJe#t GITAtonomi# re5e4es that aJe#t )o(el a#ti"it%+From internal GIT ,gastro#oli# an! !o!eno#oli# re5e4es ,gastroileal re5e4 ,enterogastri# re5e4 ,!e&e#ation re5e4From e4ternal GIT+ inhi)ition ,$eritoneo,intestinal re5e4 ,reno,intestinal re5e4 ,"esi#o,intestinal re5e4 ,somato,intestinal re5e4THANK YOU