- Journal of Experimental and Clinical Medicine
- Volume:16 Issue:3
- Sıçan İzole Duodenum Ve İleumunda GABA’nın Etkileri
Sıçan İzole Duodenum Ve İleumunda GABA’nın Etkileri
Authors : SM KESİM
Pages : 0-0
Doi:10.5835/jecm.v16i3.708
View : 36 | Download : 14
Publication Date : 2009-12-23
Article Type : Other Papers
Abstract :The Effects of GABA in Isolated Rat Duodenum and Ileum The actions of Y-aminobutyric acid insert ignore into journalissuearticles values(GABA); and the receptor selective agonists muscimol insert ignore into journalissuearticles values(GABAA);, insert ignore into journalissuearticles values(±); baclofen insert ignore into journalissuearticles values(GABAB); on spontaneous activity of rat duodenum and ileum were studied in vitro. GABA insert ignore into journalissuearticles values(10`12 M-10`5 M);, muscimol insert ignore into journalissuearticles values(10`u M-10`3 M); induced concentration-dependent contraction in isolated rat duodenum and ileum. GABA- and muscimol-induced concentration-dependent contraction was competitively antagonized by 10`6 M bicuculline. Their ED50 values were similar. 10`4 M picrotoxin antagonized the effect of GABA and muscimol but did not the effects of insert ignore into journalissuearticles values(±); baclofen. insert ignore into journalissuearticles values(±); Baclofen insert ignore into journalissuearticles values(10`7 M-10`3 M); induced concentration-dependent contraction while at higher doses insert ignore into journalissuearticles values(3xl0`3 M-3xl0`2 M); caused only relaxation. The effects of insert ignore into journalissuearticles values(± baclofen was competitively antagonized by 10`5 M CGP35348 but did not affect by bicuculline. GABA- muscimol-and insert ignore into journalissuearticles values(±); baclofen-induced contraction antagonized by 3xl0`6 M atropine but did not affect by hexamethonium insert ignore into journalissuearticles values(3xl0`4 M);, reserpine insert ignore into journalissuearticles values(3xl0`6 M);, indometacin insert ignore into journalissuearticles values(10`5 M);, aminophylline insert ignore into journalissuearticles values(2xl0`4 M); or naloxone insert ignore into journalissuearticles values(10`5 M); pretreatment. insert ignore into journalissuearticles values(±); Baclofen induced relaxation not affected by atropine insert ignore into journalissuearticles values(3xl0`6 M);, naloxone insert ignore into journalissuearticles values(10`5 M);, aminophylline insert ignore into journalissuearticles values(2xl0-4 M);, reserpine insert ignore into journalissuearticles values(3xl0`6 M);, hexamethonium insert ignore into journalissuearticles values(3xl0`4 M); pretreatment. These results show that GABAergic actions in isolated rat duodenum and ileum are mediated by two pharmacologically distinct neural receptor populations, the GABAA and acetylcholine release from isolated rat duodenum and ileum and by this way can induce contractions. There are also GABAB receptors on excitatory and inhibitory non-adrenergic non-cholinergic insert ignore into journalissuearticles values(NANCj neurons and agonist action at these neurons and the effect of agonists to these receptors results in contraction and relaxation. Sıçan izole duodenum ve ileumunun spontan aktivitesi üzerine y-aminobutirik asid insert ignore into journalissuearticles values(GABA); ve selektif reseptör agonistleri musimol insert ignore into journalissuearticles values(GABAA); ve insert ignore into journalissuearticles values(±); baklofen insert ignore into journalissuearticles values(GABAB);`in etkileri invitro olarak çalışılmıştır. Sıçan izole duodenum ve ileumunda GABA 10`12 M-10`5 M, musimol 10`11 M-10`3 M doz aralıklarında konsantrasyona bağımlı kasılmaya neden oldu. GABA ve musimolün neden olduğu kasılmalar 10`6 M bikukulin ile kompetitif olarak antagonize oldu. GABA ve musimolün ED50 değerleri benzerdi. 10`4 M pikrotoksin GABA ve musimolün etkisini antagonize etti. Fakat insert ignore into journalissuearticles values(±); baklofeni etkilemedi. insert ignore into journalissuearticles values(±); Baklofen 10`7 M-10`3 M doz aralıklarında konsantrasyona bağımlı kasılmaya neden olurken, yüksek dozlarda insert ignore into journalissuearticles values(3xl0`3-3xl0`2); yanlız gevşemeye neden oldu. insert ignore into journalissuearticles values(±); Baklofenin etkisi 10`5 M CGP35348 tarafından kompetitif olarak antagonize oldu. Bikukulin ise etkilemedi. GABA, musimol ve insert ignore into journalissuearticles values(±); baklofenin neden olduğu kasılmalar 3x10`6 M atropin tarafından antagonize olurken, heksametonyum insert ignore into journalissuearticles values(3xl0`4 M);, rezerpin insert ignore into journalissuearticles values(3xl0`6 M);, indometazin insert ignore into journalissuearticles values(10`5 M);, aminofilin insert ignore into journalissuearticles values(2xl0`4 M); ve nalokson insert ignore into journalissuearticles values(10~5 M); tarafından antagonize edilemedi. insert ignore into journalissuearticles values(±); Baklofenin neden olduğu gevşemeler atropin insert ignore into journalissuearticles values(3x10`6 M);, nalokson insert ignore into journalissuearticles values(10~5 M);, aminofilin insert ignore into journalissuearticles values(2x10-4 M);, rezerpin insert ignore into journalissuearticles values(3xl0`6 M);, heksametonyum insert ignore into journalissuearticles values(3xl0`4 M); ile önlenemedi. Bu sonuçlar göstermiştir ki sıçan izole duodenum ve ileumundaki GABAerjik etkiler GABAA ve GABAB bölgeleri olmak üzere iki farklı farmakolojik reseptör aracılığı ile oluşmaktadır. GABA, sıçan izole duodenum ve ileumunda postsinaptik GABAA reseptörler ile asetilkolin sahmmını arttırarak kasılmaya neden olmaktadır. Keza eksitatör ve inhibitor nonadrenerjik-nonkolinerjik insert ignore into journalissuearticles values(NANC); nöronlar üzerinde GABAB reseptörler bulunmaktadır ve bu reseptörlere agonistlerin etkisi sonucu kasılma ve gevşeme meydana gelmektedir.Keywords :
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