Dopamin Reseptör Agonisti Maddelerin Sıçan Beyni Striatal Dilimlerinde Kolin ve Asetilkolin Salıverilmesine, Doku Kolin, Asetilkolin ve Fosfolipid Düzeylerine Etkisi

Authors : Ismail Hakkı Ulus

Pages : 195-208

View : 48 | Download : 10

Publication Date : 2010-12-01

Article Type : Other

Abstract :AİM: The aim of the study was to determine effects of dopamine receptor agonist on acetylcholine and choline release from rat brain striatal slices and tissue levels of acetylcholine, choline and phospholipid. Methods: Spraque-Dawley rats 250-350 g were decapitated and their brains were rapidly removed, the striata were dissected and sliced with 0.3 mm thickness. Slices were perfused with heated 37 °C and oxygenated 95% O2 + 5% CO2 Krebs medium 0.6 ml/min under basal and stimulated either with high K+ or electrically conditions with presence of various concentrations of dopamine receptor agonists. Acetylcholine and choline contents of the perfusates, and tissue levels of acetylcholine, choline, protein, DNA and phospholipids were assayed Results: Dopamine receptor agonists [apomorphine 1-100 μM , dopamine 1-100 μM , bromocriptine 0.1-10 μM , piripedil 1-100 μM , quinpirole 1 and 10 μM and SKF 38393 1 and 10 μM failed to alter amounts of acetylcholine and choline released into the perfusate from striatal slices under basal conditions. While selective D1 receptor agonist SKF 38393 increased acetylcholine release at 100 μM. When the slices depolarized by high K+ 50 μM or stimulated electrically 15 Hz, 1 ms, 80 mA release of acetylcholine increased by 7-20 folds. Apomorphine, piribedil or quinpirole, but not dopamine, bromocriptine or SKF 38393, decreased acetylcholine release, by concentration dependent manner, during K+ depolarization and electrical stimulation. Dopamine receptors agonists failed to alter choline release, tissue levels of acetylcholine, choline and phospholipids at used concentrations. Conclusion: These data show that dopamine receptor agonists have no effects on acetylcholine and choline release from the striatal slices under basal perfusion conditions, while some of agonists i.e., apomorphine, piribedil and quinpirole suppressed acetylcholine release from the stimulated slices. Dopamine receptor agonists have no effect on choline release and tissue contents of acetylcholine, choline and phospholipids
Keywords : Dopamine, choline, acetylcholine, phospholipid, rat