Enalaprilin Diyabetik Sıçan Mide Dokusunda Ghrelin Ekspresyonuna Etkileri

ÖZET Amaç: Ghrelin, insülin salgılanması ve glukoz metabolizması üzerine etkili, büyük miktarda mideden salgılanan peptid yapılı bir hormondur. Bu çalışmada, streptozotosin (STZ) ile oluşturulan deneysel diyabet modelinde enalaprilin, sıçan mide dokusundaki ghrelin ekspresyonu üzerine etkilerinin incelenmesi amaçlandı. Gereç ve Yöntem: Çalışmada, 24 adet 8 haftalık Wistar albino cinsi erkek sıçanlar kullanıldı. Deney hayvanları her grupta 6 hayvan olacak şekilde 4 gruba ayrıldı. Kontrol grubuna deney süresi olan 6 hafta boyunca hiçbir uygulama yapılmadı. Tampon grubuna sadece 0,1 M fosfat-sitrat tamponu intraperitoneal (i.p) olarak enjekte edildi. Diyabet grubuna 50 mg/kg tek doz STZ 0,1 M fosfat-sitrat tamponunda çözdürülerek i.p olarak uygulandı. Diyabet+enalapril grubuna ise 50 mg/kg tek doz STZ 0,1 M fosfat-sitrat tamponunda çözdürülerek i.p olarak uygulanmasından sonra diyabetin oluşumunu takiben enalapril 5 mg/kg/gün oral olarak verildi. Deney sonunda sıçanlar anestezi altında dekapite edildi ve mide dokuları çıkartıldı. Rutin takipler yapılarak dokular parafin bloklara gömüldü. Bloklardan alınan kesitlere ghrelin ekspresyonu için avidin-biotin-peroksidaz yöntemi uygulandı. Ghrelin ile pozitif boyanmış hücreler, eyepiece gratikül ile sayılarak istatistiksel analizleri yapıldı. Bulgular: Ghrelin pozitif hücrelerin sayısı, kontrol ve tampon grupları arasında istatistiksel olarak anlamlı farklılık göstermedi. Diyabet grubunda, kontrol ve tampon gruplarına göre belirgin azalma görüldü. Diyabet+enalapril grubundaki ghrelin pozitif hücrelerde, diyabet grubuna göre anlamlı bir artış vardı. Sonuç: Deneysel diyabetin sıçan mide dokusunda ghrelin pozitif hücre sayısını azalttığı, tedavi olarak verilen enalaprilin bu hücrelerin sayısını arttırdığı, ileride yapılacak daha kapsamlı çalışmalarla diyabetik gastroparezis patofizyolojisinin aydınlatılmasında ghrelinin de görev alabileceği kanaatine varıldı.

ABSTRACT The Effects of Enalapril on Ghrelin Expression at Diabetic Rat Stomach Tissue

The Effects of Enalapril on Ghrelin Expression at Diabetic Rat Stomach Tissue Objective: Ghrelin is a peptid hormone that is released largely from stomach and has effects on insulin secretion and glucose metabolism. The aim of this study was to determine the effects of enalapril on ghrelin expression at streptozocin (STZ) induced diabetes mellitus stomach tissues in rats. Material and Method: We used 24 male Wistar albino rats that were 8 weeks age. The rats were divided into 4 groups that have 6 animals in each groups. No application was made to control group. To the buffer group, only 0,1 M phosphate-citrate buffer was injected intraperitoneally (i.p). To the diabetic group 50 mg/kg STZ solved in phosphate-citrate buffer was injected. In diabetes+enalapril group, 50 mg/kg STZ was injected and enalapril was given 5 mg/kg/day orally after development of diabetes. Finally rats were decapitated and stomach tissues were removed. With routine procedures, tissues were embedded in paraphine blockes. For ghrelin expression avidin-biotin-peroxidase method was applied. Ghrelin positive cells were counted with eyepiece gratucule and statistical analysis was performed. Results: Statistically, the number of ghrelin positive cells did not show significiant difference between control and buffer group. In comporation with control and buffer group there was decrease at diabetic group. In comparison with diabetic group, there was significant increase at diabet+enalapril group. Conclusion: Experimental diabetes decreases ghrelin positive cells, enalapril increases ghrelin positive cells at rat stomach. It was concluded that with more further comprehensive studies, ghrelin may contribute to the elucidation of pathophysiology of diabetic gastroparesis.

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