Fare colliculus inferior sinir hücreleri üzerine asotilkolinin etkileri

Bu çalışmada nörotransmitterlerden asetilkolinin colliculus inferiore sinir hücrelerini ne şekilde etkilediğinin belirlenmesi amaçlandı. Fare colliculus inferiore'unda yer alan sinir hücrelerinden tüm hücre patch clamp tekniğini kullanılarak hücre içi kayıtlar alındı. Düzenli ateşleme modeli oluşturan sinir hücrelerinin kendiliğinden oluşan aktiviteleri ve katot ile anot akımları uygulanarak uyarılan aktiviteleri kaydedildi. Küçük miktardaki katot akım uygulamaları (0.05-0.15 nA) ile çok sayıda aksiyon potansiyeli oluşturuldu. Dinlenme zar potansiyelinin anot akımlarla hiperpolarize edildikten sonra aynı miktarlarda katot akım uygulamalarına yanıt olarak, aynı hücrelerde uyarılan aksiyon potansiyel sayısının belirgin olarak azaldığı gözlendi. Perfüzyon solusyonu içerisinde uygulanan asetilkolinin (0.05 mM), dinlenme zar potansiyelini 17 mV değerinde depolarize ettiği, kendiliğinden oluşan aksiyon potansiyel sayısını belirgin olarak artırdığı, ve membran potansiyelinde dalgalanmalar meydana getirdiği gözlendi. Sonuç olarak, asetilkolinin colliculus inferiore'un sinir aktivitesini artırdığı belirlendi

Anahtar Kelimeler:

asetilkolin, sinir hücresi

Effects of acethylecholin on mice inferior colliculus neurons

In this study, it was aimed to study the effects of acethylcholine, a neurotransmitter, on neurons in the inferior colliculus. Intracellular recordings using the whole cell patch clamp technique were made from neurons of mice inferior colliculus. Spontaneous activity and the evoked responses elicited with depolarizing and hyperpolarizing current pulses were recorded from neurons with regular firing pattern. Small amounts of current injections (0.05-0.15 nA) caused the cells to fire many action potentials. The same amount of currents following the preconditioning hyperpolarizing pulses ended up with less action potentials. The application of acetylcholine added in the perfusing solution (0.05 mM) depolarized the resting potential by 17 mV, increased the number of action potential occurred spontaneously and caused the membrane potential record to be uneven. In conclusion, acethylcholine increased the activity of inferior colliculus.

Keywords:

acetylcholine, neurons,

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