SIÇANLARDA DENEYSEL DİYABETİN ÖĞRENMEYE ETKİSİ

Abstract

Diabetes mellitus'un çeşitli doku ve organlarda hasara neden olduğu bilinmektedir. Sinir sisteminde, özellikle merkezi sinir sisteminde yaptığı hasar nedeni ile bilişsel fonksiyonları bozduğu da bildirilmektedir. Ancak, literatürde bu konu ile ilgili çelişkili bulgulara rastlanmaktadır. Bu araştırmada 10'u kontrol grubunda, 10'u deney grubunda olmak üzere toplam 20 adet Sprague Dawley, 2 aylık erkek sıçan ile çalışılmıştır. Deneysel diyabet oluşturmak için 60 mg/kg streptozotosin ip. yolla uygulanmış, yer bulma öğrenmesinin değerlendirilmesi için Morris Su Tankı kullanılmıştır. Kontrol ve diyabetik deney grubu sıçanlarda, platformu bulmak için geçirilen toplam süre ve platformlu 1/2'lik alanda geçirilen sürenin toplam sürenin yüzdesi cinsinden değerlerinin istatistiksel olarak grup içi ve gruplar arası karşılaştırması yapılıp, diyabetin yer bulma öğrenmesi üzerindeki etkisi değerlendirilmiştir. İstatistiksel değerlendirmelerde öğrenme fazı için her bir gündeki öğrenme performanslarının grup içi karşılaştırmasında tekrarlı ölçümlerle ANOVA, test fazı için gruplar arası karşılaştırmada eşleştirilmemiş t testi kullanılmıştır. Değerlendirme sonunda diyabet oluşturulan sıçanlarda streptozotosin uygulamasını takip eden ilk dört gün öğrenme performansının kontrol grubundaki sıçanlara göre daha iyi olduğu saptanmıştır. Bulgulara göre diyabetin akut fazında öğrenmenin kontrol grubuna göre daha iyi olması, akut fazda hücresel hasar gelişmemesi ve oluşan hiperglisemi ile ilişkilendirilmiştir

Keywords

• Deneysel diyabet, streptozotosin, sıçan, öğrenme

The Effect of Experimental Diabetes on the Ability of Learning in Rats

Abstract

Diabetes mellitus is known to cause damage in various tissues and organs. it has been reported to cause cognitive functional disorders due to damage of the nervous system, in particular the central nervous system. However contradictory findings related to this condition are encountered in literature. This research was conducted on a total of 20 male rats, including a control group consisting of 10 young rats of Sprague Dawley and 2 months of age and an experimental group comprising of 10 rats in which diabetes was induced by means of streptozotocin administration. Experimental diabetes was induced by means of administring 60mg/kg streptozotocin (ip.) and their ability of spatial learning was evaluated by using a Morris water maze. The total duration of time spent to find the platform and the duration of time spent in the half of the field including the platform in a value representing the percentage in the total time were compared statistically within and between the rats included in the control and diabetic experiment groups so as to assess the effect of diabetes on the ability of learning to position in rats. The comparison of the learning phase for learning performances displayed on each day within groups was statistically analysed by means of repeated measurements with the ANOVA test whereas the test phase was compared between groups with the unpaired t test. According to the evaluation, the learning performance of rats with induced diabetes was found to be better throughout the first four days after streptozotocin administration in comparison to the rats included in the control group. The findings obtained in this research which point out to better learning performance in the acute phase of diabetes have been related to the absence of cell damage and occurrence of hyperglycemia in the acute phase

Keywords

• Experimental diabetes, streptozotocin, rat, ability to learning

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